@proceedings {1024, title = {Electromagnetic Vector Sensor Ionospheric Sounder (EMVSIS)}, year = {2026}, month = {03/2026}, publisher = {HamSCI}, address = {Newington, CT}, abstract = {Ground-based ionosondes, also known as ionospheric sounders, are a bedrock sensor modality used by the space science community to monitor the bottom-side ionosphere. These HF radar systems have been used for decades to remotely measure the electron density and ion-drifts of this charged layer of the atmosphere. These systems have evolved as new technologies have come on the scene; one current example are electro-magnetic vector sensor antennas, which are compact arrays that measure the six components of an impinging electro-magnetic wave, allowing for estimation of direction of arrival and polarization. We will present a design that uses this new antenna technology, takes advantage of MIMO radar concepts and new waveform coding techniques. We call this system the Electro-Magnetic Vector Sensor Ionospheric Sounder (EMVSIS). The various design decisions and challenges will be discussed along with future improvements. We will preliminary results from various measurement campaigns and the types of validation and verification methods we are performing.}, author = {John Swoboda and Ryan Volz and Juha Vierinen and Frank Lind} } @proceedings {1018, title = {The Heliophysics Application Programming Interface on the PSWS}, year = {2026}, month = {03/2026}, publisher = {HamSCI}, address = {Newington, CT}, abstract = {One of the major enhancements being developed for the Personal Space Weather Network System is our implementation of the Heliophysics Application Programming Interface. This interface is being developed with help from Dr Robert Weigel of George Mason University to make HamSCI data more accessible to researchers. In the first version of the PSWS system, users have been able to download individual files to analysis, but this can be labor intensive and time-consuming if a lot of files are needed. The current NSF-funded effort will make the data more easily accessible to users by leveraging Python libraries that make data access transparent, such as hapiclient, hapiplot, hdpws, And SwarmPAL. This poster gives an overview of what will be included and how you will be able to use it.}, author = {William Engelke and Travis Atkison and Evan Hardt and Christian Hirschey and Gavin Ward and Annika Lee} } @proceedings {1040, title = {Introduction to Baseband Processing}, year = {2026}, month = {03/2026}, publisher = {HamSCI}, address = {Newington, CT}, abstract = {Today, much RF digital signal processing is done at baseband, defined here as a signal with frequencies centered around DC or 0 Hz. Baseband processing is somewhat analogous to using an intermediate frequency (IF), as done in a superheterodyne receiver with typical IF frequencies of 455 kHz (AM) or 10.7 MHz (FM), but where the IF is at 0 Hz and where the resulting baseband signal contains both positive and negative frequencies. Just as intermediate frequencies of superheterodyne receivers gave advantages in analog receivers, baseband processing gives certain advantages in digital receivers. Furthermore, most modern Software Defined Radios output in-phase / quadrature (IQ) data streams, containing both amplitude and phase information and centered at baseband. This includes the IQ output of the popular {\textquotedblleft}ka9q-radio{\textquotedblright} software environment used in HamSCI development of the Personal Space Weather Station system. A good understanding of baseband processing and its typical applications is thus useful. In this tutorial, we will introduce a common definition of baseband processing and explore its uses. The presentation will include a reminder of Fourier / frequency domain and complex signal representations. We will discuss the advantages of processing of IQ signals at baseband and will give examples of their use in common tasks. These include signal demodulation and filtering, including asymmetric filtering around 0 Hz. A brief discussion on creating a baseband signal from a non-baseband signal and converting a baseband signal to a non-baseband signal will also be presented. Interactive demonstrations will be provided as well for active learning, easy modification, and experimentation. }, author = {Bill Liles and Philip Erickson and Ethan Miller} } @proceedings {1034, title = {The Personal Space Weather Network System and Its Development}, year = {2026}, month = {03/2026}, publisher = {HamSCI}, address = {Newington, CT}, abstract = {

This talk gives an overview of the Personal Space Weather Network system : overall architecture, how uploading of data from stations works, how data is visualized and cross-referenced. It explains how to find data based on your research interests, with tips on how to work with digital_rf datasets (a large part of the collection), with examples of analysis work previously done. Finally, it includes an overview of the enhancements that are planned to be implemented over the next 2 to 3 years.

}, author = {Christian Hirschey and Gavin Ward and William Engelke and Evan Hardt and Annika Lee and Travis Atkinson} } @proceedings {1011, title = {Study of HF Channel Conditions Using WWV/WWVH test Modulation Signals}, year = {2026}, month = {03/2026}, publisher = {HamSCI}, address = {Newington, CT}, abstract = {

This paper summarizes a year-long data-collection and analysis effort using test signals transmitted by WWV and WWVH every hour. Multipath and Doppler fading profiles for two links from Massachusetts to Boulder, Colorado (WWV), and Hawaii (WWVH) were calculated. Correlations between multipath and Doppler profiles and Kp index were calculated. This paper also proposes a set of techniques for processing and using the WWV/H test signals.

}, author = {Jay Weitzen and Jocelyn Frechette and Elliot Lebsack} } @proceedings {1032, title = {Why You Should Attend the Youth on the Air Camp}, year = {2026}, month = {03/2026}, publisher = {HamSCI}, address = {Newington, CT}, abstract = {Why we believe every young ham radio operator, aged 15-25{\textemdash}whether you{\textquoteright}re a seasoned pro or newly licensed{\textemdash}should attend YOTA camp}, author = {Jack Roberts and Taylor Laub} } @proceedings {927, title = {EZIE-Mag: A low cost, science quality, magnetometer suite enabling global coverage}, year = {2025}, month = {03/2025}, publisher = {HamSCI}, address = {Newark, NJ}, abstract = {

EZIE-Mag suite is an ultra-low cost, science quality measurements that enable the global observational coverage that is required to produce space weather nowcasting and forecasting. Industry have developed solutions that allow a low cost solution. We show the hardware solution, the OS, the post-processing solution, and the educational package.

}, author = {Jesper Gjerloev and R. Barnes and E. Adebayo and L. Kepko and T. Cline and N. Mosavi-Hoyer and J. Leibert and L. Regoli and M. Freil and D. Oztruk and A. Cohen and J. Fitzer} } @proceedings {957, title = {How Do We Put a HamSCI Personal Space Weather Station in Antarctica?}, year = {2025}, month = {03/2025}, publisher = {HamSCI}, address = {Newark, NJ}, abstract = {

We present initial ideas on how to place a HamSCI Personal Space Weather Station at United States Antarctic Research Stations.

}, author = {Rebecca Potter and Nina Tormann and Christine Zakzewski and Majid Mokhtari and Nathaniel Frissell and Ken Martin and Jermey McLynch and Hyomin Kim and Gareth Perry and David McGaw and James LaBelle and Tedi Godfrey and Michael Hartje and Gwyn Griffiths and Rob Robinett and Paul Elliott} } @proceedings {937, title = {Radio Wave and GPS Scintillation Impacts of the 10 May 2024 G5 Geomagnetic Storm Observed at the United States Military Academy}, year = {2025}, month = {03/2025}, publisher = {HamSCI}, address = {Newark, NJ}, abstract = {

Beginning on 7 May 2024, a sequence of nine CMEs erupted from solar active region 3664, with several merging together in transit through the solar wind towards Earth. The first combined CME impacted the dayside magnetosphere on 10 May and triggered an extreme G5 geomagnetic storm. The storm commenced at 16:37 UTC on 10 May, reached maximum intensity at 03:33 UTC on 11 May, and persisted into recovery through May 13. An array of instruments were online throughout the Hudson River Valley during the event, including scientific grade GPS receivers, amateur radios, Personal Space Weather Stations and a ground magnetometer. The Hudson Valley is located in the mid-latitude region and ranges from just upstate of New York City in Yonkers, NY to as far north as Troy, NY. At these mid-latitudes, the storm induced beautiful red and green auroral activity, amplitude and phase scintillation of GPS signals, flare- and storm-induced radio blackouts within the amateur radio bands, plasma density modifications, geoelectric and geomagnetic field perturbations, plasma flows, etc. Here we examine primarily the radio wave, scintillation and ground magnetic impacts of this geomagnetic storm as observed over West Point.

}, author = {Jason Derr and Joanna Halfhill and Diana Loucks and Stephen Hamilton} } @proceedings {959, title = {A Statistical Study of Ion Temperature Anisotropy Using AMISR Data}, year = {2025}, month = {03/2025}, publisher = {HamSCI}, address = {Newark, NJ}, abstract = {

One of the longstanding problems in ionospheric science is that we typically assume the F-region ion temperature to be an isotropic Maxwellian, meaning the ion temperature is the same in all directions with respect to the magnetic field. However, works from St.-Maurice et al., (1976), and Raman et al., (1981), show that in times of heating due to moderate to strong electric fields (above 50 mV/m), the O+ velocity distribution distorts, and the ion temperature becomes anisotropic. Here, data from advanced modular incoherent scatter radars, or AMISRs, like the resolute bay incoherent scatter radars RISR-N and RISR-C (North and Canada, respectively), and the poker flat incoherent scatter radar, PFISR, taken during strong heating events (generally events consistently above 1500 K for greater than 15 minutes) are used to resolve a temperature perpendicular to the magnetic field and a temperature parallel to the magnetic field. This calculation is performed on radar scanning modes where two or more beams have F-region range gates that overlap in geomagnetic coordinates and have at least 10 degrees difference in their aspect angle This means that the two beams are theoretically scanning the same F-region plasma in the same magnetic flux tube undergoing the same physical processes with similar conditions. Lower beam modes are preferred to reduce error in imaging the plasma. This presentation will provide preliminary results derived through this technique.\ 

}, author = {Aidan Thayer and Lindsay Goodwin and William Longley and Jean Pierre St Maurice} } @proceedings {820, title = {Citizen Science: Development of a Low-Cost Magnetometer System for a Coordinated Space Weather Monitoring}, year = {2024}, month = {03/2024}, publisher = {HamSCI}, address = {Cleveland, OH}, abstract = {

As part of Ham Radio Science Citizen Investigation (HamSCI) Personal Space Weather Station (PSWS) project, a low-cost, commercial off-the-shelf magnetometer has been developed to provide quantitative and qualitative measurements of the geospace environment from the ground for both scientific and operational purposes at a cost that will allow for crowd-sourced data contributions. The PSWS magnetometers employ a magneto-inductive sensor technology to record three-axis magnetic field variations with a field resolution of ~3 nT at a 1 Hz sample rate. Crowd-sourced data from the PSWS systems will be collected into a central archive for the purpose of public access and analyzation along with space weather research. Ultimately, data from the PSWS network will combine the magnetometer measurements with high frequency (HF, 3-30 MHz) radio observations to monitor large scale current systems and ionospheric disturbances and events due to drivers from space and the atmosphere alike. A densely-spaced magnetometer array, once established, will demonstrate their space weather monitoring capability to an unprecedented spatial extent. Magnetic field data obtained by the magnetometers installed at various locations in the US are presented and compared with the existing magnetometers nearby, demonstrating that the performance is entirely satisfactory for scientific investigations.

}, author = {Joseph Visone and Hyomin Kim and David Witten and Julius Madey and Nathaniel A. Frissell and John Gibbons and William D. Engelke and Anderson Liddle and Nicholas Muscolino and Zhaoshu Cao} } @article {913, title = {Citizen science: Development of a low-cost magnetometer system for a coordinated space weather monitoring}, journal = {HardwareX}, volume = {20}, year = {2024}, month = {Jan-12-2024}, pages = {e00580}, abstract = {
As part of Ham Radio Science Citizen Investigation (HamSCI) Personal Space Weather Station (PSWS) project, a low-cost, commercial off-the-shelf magnetometer has been developed to provide quantitative and qualitative measurements of the geospace environment from the ground for both scientific and operational purposes at a cost that will allow for crowd-sourced data contributions. The PSWS magnetometers employ a magneto-inductive sensor technology to record three-axis magnetic field variations with a field resolution of\ 3 nT at a 1 Hz sample rate. The measurement range of the sensor is\ \ nT) and is valid over a temperature range of -40 {\textdegree}C to +85 {\textdegree}C. Data from the PSWS network will combine these magnetometer measurements with high frequency (HF, 3{\textendash}30 MHz) radio observations to monitor large-scale current systems and ionospheric disturbances due to drivers from both space and the atmosphere. A densely-spaced magnetometer array, once established, will demonstrate their space weather monitoring capability to an unprecedented spatial extent. Magnetic field data obtained by the magnetometers installed at various locations in the US are presented and compared with the existing magnetometers nearby, demonstrating that the performance is very adequate for scientific investigations.
}, keywords = {magnetometer}, issn = {24680672}, doi = {10.1016/j.ohx.2024.e00580}, url = {https://www.sciencedirect.com/science/article/pii/S2468067224000749}, author = {Kim, Hyomin and Witten, David and Madey, Julius and Frissell, Nathaniel and Gibbons, John and Engelke, William and Liddle, Anderson and Muscolino, Nicholas and Visone, Joseph and Cao, Zhaoshu} } @proceedings {835, title = {Comparative Analysis of Medium Scale Travelling Ionospheric Disturbances: Grape PSWS vs. SuperDARN}, year = {2024}, month = {03/2024}, publisher = {HamSCI}, address = {Cleveland, OH}, abstract = {

Medium Scale Traveling Ionospheric Disturbances (MSTIDs) are periodic fluctuations in ionospheric electron density associated with atmospheric gravity waves. They are characterized by wavelengths of 50-500 kilometers and periods of 15-60 minutes. This study presents initial findings from a comparative analysis of MSTID observations sourced from two distinct systems: the Super Dual Auroral Radar Network (SuperDARN) and the Grape Personal Space Weather Station (PSWS). The Grape PSWS, developed by the Ham Radio Science Citizen Investigation (HamSCI), is a small ground-based remote sensing device aimed at monitoring space weather parameters, including MSTIDs. It achieves this by monitoring a 10 MHz transmission from WWV, a National Institute of Standards and Technology (NIST) time standard station located near Fort Collins, Colorado, USA. In contrast, SuperDARN comprises a global network of high-frequency radars that offer extensive coverage of ionospheric plasma motion. This comparative investigation focuses on aligning MSTID observations obtained from Grape PSWS data with SuperDARN radar data. By investigating datasets from both platforms, these findings serve as initial results for an ongoing investigation of MSTIDs, laying the groundwork for a comprehensive understanding of their dynamics and impacts on ionospheric variability and space weather.

}, author = {Veronica I. Romanek and Nathaniel A. Frissell and Bharat Kunduri and J. Michael Ruohoniemi and Joseph Baker and William Liles and John Gibbons and Kristina Collins and David Kazdan and Rachel Boedicker} } @proceedings {853, title = {Earth{\textquoteright}s Magnetic Field Migration and Its Effects on HF Propagation}, year = {2024}, month = {03/2024}, publisher = {HamSCI}, address = {Cleveland, OH}, abstract = {

Propagation of radio waves in Earth{\textquoteright}s ionosphere and atmosphere critically depends on the strength and orientation of Earth{\textquoteright}s background magnetic field, due to the fact that electrons move much more readily along field lines than across them.\  The background magnetic field evolves continuously, driven by currents and other processes inside the planet{\textquoteright}s molten core.\  In particular, since 1990, the north magnetic pole has been migrating at an increased speed relative to its rate over most of the past century, and now moves more than 40 km/year.\  However, the south magnetic pole migration is considerably slower.\  The combination of these two effects has caused the global configuration of the geomagnetic field to change significantly.\  We will describe the sustained drift of magnetic field line locations over the last 40 years, with an emphasis on mid-latitudes where a large number of amateur radio operations take place.\  We will then provide estimates of induced changes in HF propagation over that time, using multiple models, and draw conclusions regarding the general climatology of propagation in various well used bands.

}, author = {Philip J. Erickson and William Liles} } @proceedings {874, title = {Effect of X-class Solar Flare on 40 Meter Propagation}, year = {2024}, month = {03/2024}, publisher = {HamSCI}, address = {Cleveland, OH}, abstract = {

WSPR data for North America is summarized to examine the impact of a reported x-class solar flare.\  The data is divided into distance categories to examine impact on different propagation methods, assuming that distance indicates propagation method. Very short distance (under 100 mile) for non-ionospheric, short distance (100 to 500 miles) for NVIS, medium distance (500-1500 miles) for E-layer propagation and longer distance (over 1500 miles) for F-layer.\  Signal to noise ratio is plotted by hour for the date of the flare. The impact of the flare is shown as a sudden decline in SNR for all distance ranges.\  While communications under 100 miles were initially presumed to involved non-ionospheric propagation, the flare impact at this distance indicates otherwise. WSPR data is also evaluated for its suitability in propagation analysis, noting strengths and weaknesses.

}, author = {Vincent LeVeque} } @proceedings {829, title = {Plans to Observe Changes to the Ionosphere During the April 8 Eclipse Using Doppler Shifts of AM Broadcast Stations}, year = {2024}, month = {03/2024}, publisher = {HamSCI}, address = {Cleveland, OH}, abstract = {

Variations in the ionosphere can be tracked by observing the Doppler-shifted carriers of clear-channel AM broadcast stations.\  An expansive system of receivers using Software-Defined Radios, frequency stabilized by GPS is being deployed to collect data in the eastern United States.\  This network is expected to be able to detect and track changes due to the shadow of the April 8, 2024 Total Eclipse of the Sun.

}, author = {David McGaw and James LaBelle and John Griffin and Terrence Kovacs and Margaret Klein and Jack Bonneau and Justin Lewis and Jackson Gosler} } @proceedings {848, title = {Sensitivity analysis of ray-tracing techniques to ionospheric electron density profiles}, year = {2024}, month = {03/2024}, publisher = {HamSCI}, address = {Cleveland, OH}, abstract = {

The Earth{\textquoteright}s ionosphere, a weakly ionized plasma embedded in a magnetic field, constitutes an anisotropic and dispersive medium for the propagation of HF radio waves. Ray-tracing is a powerful and useful technique, included in several radar simulation codes, that allows determining the path of these radio waves through the ionosphere in order, for example, to locate and track a target. Depending on the degree of precision needed, ray-tracing requires more or less precise knowledge of ionospheric conditions along the propagation path. A sensitivity analysis is performed in this work to determine the effect of different electron density height profiles in ray path features considering a fully analytical approach and two ray-tracing algorithms. The analytical approach is based on the quasi-parabolic electron density height distribution which allows for the derivation of exact equations for ray path parameters. The first ray-tracing algorithm consists of Snell-law application to a two-dimensional ionosphere which is layered into thin homogeneous slabs with a constant refractive index. The second algorithm implements the code of Jones and Stephenson, introduced in 1975, and numerically solves Haselgrove ray equations to trace ray paths through an anisotropic medium whose refractive index varies in three dimensions. The three methodologies used to assess an HF signal ray path must assume an electron density height profile which strongly affects any output parameter that depends on the signal traveling path. In particular, the analytical approach, even though it is less accurate, it is considerably faster than any numerical ray-tracing technique. This sensitivity analysis approach allows estimating the percentage variation of ray-tracing outputs which may serve to analyze the errors introduced by ionospheric transient disturbances which cannot be easily included in models considered in ray-tracing algorithms.

}, author = {Ana G. Elias and Mariano Fagre and Zenon Saavedra and Adrian Llanes and Blas F. de Haro Barbas} } @proceedings {750, title = {AC Motor Drive With Power Factor Correction Using Arduino}, year = {2023}, month = {03/2023}, publisher = {HamSCI}, address = {Scranton, PA}, abstract = {

By using various electrical and computer engineering concepts, this project incorporates different sectors explored through current curriculum. By implementing these concepts, a fully functioning AC motor controller will be designed. The project is split into 5 groups: AC to DC power conversion, DC to AC power control, power factor correction, capacitor bank control, and Arduino interfacing, all working on separate critical components for the motor controller. As this is currently a work in progress, actual conclusions cannot be made, but speculation based on calculations is available.

}, author = {Christian D. Chakiris and Robert C. Brudnicki and Robert D. Troy and John A. Nelson and Matthew K. Dittmar and Augustine D. Brapoh Jr. and Milton Andrade and Sade Lugo and Aidan T. Szabo and Kenneth Dudeck} } @proceedings {691, title = {Climatology of Ionospheric Variability with MSTID Periods Observed Using Grape v1 HF Doppler Receivers}, year = {2023}, month = {03/2023}, publisher = {HamSCI}, address = {Scranton, PA}, author = {Veronica Romanek and Nathaniel Frissell and Kristina Collins and John Gibbons and David Kazdan and William Liles} } @article {797, title = {Crowdsourced Doppler measurements of time standard stations demonstrating ionospheric variability}, journal = {Earth System Science Data}, volume = {15}, year = {2023}, month = {Jan-01-2023}, pages = {1403 - 1418}, abstract = {

Ionospheric variability produces measurable effects in Doppler shift of HF (high-frequency, 3{\textendash}30 MHz) skywave signals. These effects are straightforward to measure with low-cost equipment and are conducive to citizen science campaigns. The low-cost Personal Space Weather Station (PSWS) network is a modular network of community-maintained, open-source receivers, which measure Doppler shift in the precise carrier signals of time standard stations. The primary goal of this paper is to explain the types of measurements this instrument can make and some of its use cases, demonstrating its role as the building block for a large-scale ionospheric and HF propagation measurement network which complements existing professional networks. Here, data from the PSWS network are presented for a period of time spanning late 2019 to early 2022. Software tools for the visualization and analysis of this living dataset are also discussed and provided. These tools are robust to data interruptions and to the addition, removal or modification of stations, allowing both short- and long-term visualization at higher density and faster cadence than other methods. These data may be used to supplement observations made with other geospace instruments in event-based analyses, e.g., traveling ionospheric disturbances and solar flares, and to assess the accuracy of the bottomside estimates of ionospheric models by comparing the oblique paths obtained by ionospheric ray tracers with those obtained by these receivers. The data are archived at\ https://doi.org/10.5281/zenodo.6622111(Collins,\ 2022).

}, doi = {10.5194/essd-15-1403-2023}, url = {https://essd.copernicus.org/articles/15/1403/2023/https://essd.copernicus.org/articles/15/1403/2023/essd-15-1403-2023.pdf}, author = {Collins, Kristina and Gibbons, John and Frissell, Nathaniel and Montare, Aidan and Kazdan, David and Kalmbach, Darren and Swartz, David and Benedict, Robert and Romanek, Veronica and Boedicker, Rachel and Liles, William and Engelke, William and McGaw, David G. and Farmer, James and Mikitin, Gary and Hobart, Joseph and Kavanagh, George and Chakraborty, Shibaji} } @proceedings {762, title = {Development of HamSCI PSWS Ground Magnetometer and Data Visualization on the PSWS Central Website}, year = {2023}, month = {03/2023}, publisher = {HamSCI}, address = {Scranton, PA}, author = {Hyomin Kim and Nathaniel A. Frissell and David Witten and Julius Madey and William D. Engelke and Tom Holmes and Majid Mokhtari and Scotty Cowling and Anderson Liddle and Nicholas Muscolino and Zhaoshu Cao} } @proceedings {690, title = {Evaluation of Global Ionospheric TEC Using Simultaneous Observations from Amateur Radio Networks, International Space Station, and NeQuickG Model for Space Weather Prediction}, year = {2023}, month = {03/2023}, publisher = {HamSCI}, address = {Scranton, PA}, abstract = {

Ionospheric electron density plays a significant role in long-distance communications and sky-wave propagation. Prediction of the accurate state of the ionosphere is necessary to understand the accurate signal perturbations thereby estimating the critical parameters for better signal transmission. The space weather impacts on such trans-ionospheric technological systems are evident. In this work, a web application is developed to represent the global day-to-day electron density variations from the NeQuickG model. Also, the ground-based HAM radio broadcast network hop data with different wavelengths (eg. 10 m and 20 m) and simultaneous top-side electron density with space-based International Space Station (ISS) probe data from floating point measurement units are examined. The electron density variations for the year 2017 are clearly represented. Optimization techniques are necessary to frame a denser spatial grid-based ionospheric electron density map from all the observations. It is essential to estimate the optimal weight function that can distribute the observation influence over empty grid bins with minimum error variance through a probabilistic approach. User-understandable metrics development exclusively for Amateur radio operators and civil aviation sectors is focused. In the near future, the developed web-based application could serve as a better visualization platform for space weather forecasting.

This project, Fellowship of the Ionosphere,\ is a Global Finalist in the 2022 NASA Space Apps Challenge.\ NASA Space Apps 2022 had 31,400+ registered participants from 162 counties and territories, with\ over 3000 submissions from 5327 teams. Global Finalists are ranked as one of the top 35 projects from all submissions.

}, author = {Gamal Zayed and Marcin Lesniowski and Pasumarthi Babu Sree Harsha and Matthew Downs and Daniel Metcalfe and Sila Kardelen Karabulut} } @proceedings {719, title = {An Expanded System to Track Traveling Ionospheric Disturbances and Other Effects Using Doppler-shifts of AM Broadcast Stations}, year = {2023}, month = {03/2023}, publisher = {HamSCI}, address = {Scranton, PA}, abstract = {

Traveling Ionospheric Disturbances, propagating variations in the ionosphere, can be tracked by observing the Doppler-shifted carriers of clear-channel AM broadcast stations.\  A system of receivers using Software-Defined Radios frequency stabilized by GPS has been developed, deployed and collecting data in the northeast United States.\  The existing system of 6 receivers will be built out to as many as 15 to cover much of the eastern US.\  This expanded network promises to be able to detect and track these TIDs as well as terminator, Spread-F and eclipse effects.

}, author = {David McGaw and Jackson Gosler and Justin Lewis and James LaBelle} } @article {801, title = {Heliophysics and amateur radio: citizen science collaborations for atmospheric, ionospheric, and space physics research and operations}, journal = {Frontiers in Astronomy and Space Sciences}, volume = {10}, year = {2023}, month = {Apr-11-2024}, abstract = {

The amateur radio community is a global, highly engaged, and technical community with an intense interest in space weather, its underlying physics, and how it impacts radio communications. The large-scale observational capabilities of distributed instrumentation fielded by amateur radio operators and radio science enthusiasts offers a tremendous opportunity to advance the fields of heliophysics, radio science, and space weather. Well-established amateur radio networks like the RBN, WSPRNet, and PSKReporter already provide rich, ever-growing, long-term data of bottomside ionospheric observations. Up-and-coming purpose-built citizen science networks, and their associated novel instruments, offer opportunities for citizen scientists, professional researchers, and industry to field networks for specific science questions and operational needs. Here, we discuss the scientific and technical capabilities of the global amateur radio community, review methods of collaboration between the amateur radio and professional scientific community, and review recent peer-reviewed studies that have made use of amateur radio data and methods. Finally, we present recommendations submitted to the U.S. National Academy of Science Decadal Survey for Solar and Space Physics (Heliophysics) 2024{\textendash}2033 for using amateur radio to further advance heliophysics and for fostering deeper collaborations between the professional science and amateur radio communities. Technical recommendations include increasing support for distributed instrumentation fielded by amateur radio operators and citizen scientists, developing novel transmissions of RF signals that can be used in citizen science experiments, developing new amateur radio modes that simultaneously allow for communications and ionospheric sounding, and formally incorporating the amateur radio community and its observational assets into the Space Weather R2O2R framework. Collaborative recommendations include allocating resources for amateur radio citizen science research projects and activities, developing amateur radio research and educational activities in collaboration with leading organizations within the amateur radio community, facilitating communication and collegiality between professional researchers and amateurs, ensuring that proposed projects are of a mutual benefit to both the professional research and amateur radio communities, and working towards diverse, equitable, and inclusive communities.

}, doi = {10.3389/fspas.2023.1184171}, url = {https://www.frontiersin.org/articles/10.3389/fspas.2023.1184171/fullhttps://www.frontiersin.org/articles/10.3389/fspas.2023.1184171/full}, author = {Frissell, Nathaniel A. and Ackermann, John R. and Alexander, Jesse N. and Benedict, Robert L. and Blackwell, William C. and Boedicker, Rachel K. and Cerwin, Stephen A. and Collins, Kristina V. and Cowling, Scott H. and Deacon, Chris and Diehl, Devin M. and Di Mare, Francesca and Duffy, Timothy J. and Edson, Laura Brandt and Engelke, William D. and Farmer, James O. and Frissell, Rachel M. and Gerzoff, Robert B. and Gibbons, John and Griffiths, Gwyn and Holm, Sverre and Howell, Frank M. and Kaeppler, Stephen R. and Kavanagh, George and Kazdan, David and Kim, Hyomin and Larsen, David R. and Ledvina, Vincent E. and Liles, William and Lo, Sam and Lombardi, Michael A. and MacDonald, Elizabeth A. and Madey, Julius and McDermott, Thomas C. and McGaw, David G. and McGwier, Robert W. and Mikitin, Gary A. and Miller, Ethan S. and Mitchell, Cathryn and Montare, Aidan and Nguyen, Cuong D. and Nordberg, Peter N. and Perry, Gareth W. and Piccini, Gerard N. and Pozerski, Stanley W. and Reif, Robert H. and Rizzo, Jonathan D. and Robinett, Robert S. and Romanek, Veronica I. and Sami, Simal and Sanchez, Diego F. and Sarwar, Muhammad Shaaf and Schwartz, Jay A. and Serra, H. Lawrence and Silver, H. Ward and Skov, Tamitha Mulligan and Swartz, David A. and Themens, David R. and Tholley, Francis H. and West, Mary Lou and Wilcox, Ronald C. and Witten, David and Witvliet, Ben A. and Yadav, Nisha} } @proceedings {728, title = {Institute of Electrical and Electronics Engineers at the University of Scranton}, year = {2023}, month = {03/2023}, publisher = {HamSCI}, address = {Scranton, PA}, abstract = {

The Institute of Electrical and Electronics Engineers (IEEE) is an international professional association for all things electronic engineering and electrical engineering. The mission of the IEEE is {\textquotedblleft}advancing technology for the benefit of humanity{\textquotedblright}. At the University of Scranton, we help physics and engineering majors see the possibilities of where they could end up after college in their respective fields. Weekly seminars are tailored to present the business processes involved and innovative ideas developed by various researchers, companies, and industries. The club also serves as the social network through which our students and alumni can share their experiences and form a friendship that transcends many stages of life.

}, author = {Cuong Nguyen and Veronica Romanek and Francis Lynch Jr. and Joseph Tholley and Robert Troy and Matthew Dittmar and John Nelson and Sade Lugo} } @article {736, title = {Measuring the Frequency Accuracy and Stability of WWV and WWVH}, volume = {107}, year = {2023}, month = {03/2023}, pages = {33-37}, abstract = {

Radio station WWV is known as a source of accurate time. However, since March 6, 1923, the original purpose of WWV has been to provide standard frequency signals, with signals broadcast in the LF and MF bands. As detailed in Hoy J. Walls{\textquoteright} {\textquotedblleft}The Standard-Frequency Set at WWV{\textquotedblright} in the October 1924 issue of QST, this
was in the early days of broadcast radio, when having an accurate frequency reference was essential for keeping stations from interfering with each other. A century later, the standard frequency signals remain essential to radio broadcasters, calibration laboratories, space weather researchers, and radio amateurs.

}, issn = {0033-4812}, author = {Michael A. Lombardi} } @proceedings {702, title = {The North Dakota Dual Aurora Camera Version 2.0 (NoDDAC2.0), a Platform for Citizen Science and a Use Case for Implementing Best Practices in Open Data and Collaboration}, year = {2023}, month = {03/2023}, publisher = {HamSCI}, address = {Scranton, PA}, abstract = {

The North Dakota Dual Aurora Camera (NoDDAC) is an interdisciplinary project created in collaboration with the University of North Dakota (UND), Live Aurora Network, and Aurorasaurus. Aurora cameras provide ground-truth visual data to aurora chasers and scientists but are sparse at midlatitudes (35-55{\textdegree}N). Deploying light-sensitive video and all-sky still cameras at these midlatitudes provides a valuable resource to aurora-chasing communities, as well as amateur radio operators in the auroral zone. In addition, NoDDAC data demonstrate scientific merit, as it can be correlated with radio and ionospheric propagation changes to investigate the connection between optical aurora and radio science. This project is unique; the practices of utilizing dual cameras with consumer-off-the-shelf equipment, emphasizing open data as a responsive community resource and promoting citizen science make NoDDAC an accessible resource benefiting multiple audiences. Since early 2021, NoDDAC has detected hundreds of auroras as well as notable events like STEVEs (Strong Thermal Emission Velocity Enhancement). NoDDAC is stationed at Martens Observatory (48.1{\textdegree}N, 97.6{\textdegree}W), which is operated by the UND Department of Physics and Astrophysics. Live Aurora Network provides weatherproof camera housings and their proprietary IPTimelapse software which allows for remote control of the cameras. This year we present NoDDAC2.0, the next evolution of NoDDAC funded by NASA{\textquoteright}s EPSCoR program. NoDDAC2.0 will upgrade the all-sky camera and feature a robust open-data platform to share aurora data with the public and scientists. We outline a strategy to increase the science utility of NoDDAC data, incorporating a citizen science project launching on the Zooniverse platform. We also present plans to integrate NoDDAC data into the AuroraX conjunction finder system so that satellite data can be easily correlated to aurora images. Most importantly, we are collaborating with the Nueta Hidatsa Sahnish College on the Fort Berthold Indian Reservation to install an independent aurora camera system in North Dakota. Not only does this represent a unique collaborative opportunity, but at a separation distance of 300 miles from Martens Observatory, this second camera will allow us to explore research questions relating to the precise location, height, and spatial extent of certain auroral phenomena.

}, author = {Timothy Young and Vincent Ledvina and Elizabeth MacDonald and Laura Brandt and Wayne Barkhouse and Alex Schultz and Cody Payne and Anne Mitchell and Kristian Haugen and Will Shearer and Kerry Hartman and Sasha Sillitti and Michael McCormack and Steve Collins} } @proceedings {703, title = {Observing Auroral Radio Emissions in Conjugate Hemispheres}, year = {2023}, month = {03/2023}, publisher = {HamSCI}, address = {Scranton, PA}, abstract = {

In addition to its beautiful optical displays, the aurora produces radio emissions of various types, including cyclotron harmonic emissions, auroral hiss, medium frequency burst (MFB), and auroral kilometric radiation (AKR). These emissions enable remote sensing of ionospheric processes and provide a natural laboratory for studying physics of radio emissions that also occur in planetary, solar, and astrophysical environments. Similar to the optical aurora, these radio emissions are generated separately in the northern and southern hemispheres. Nevertheless, optical aurora sometimes exhibit similar features simultaneously in the two hemispheres because aurora in both hemispheres are ultimately driven by the interaction between the solar wind and the magnetosphere. The same should be true of radio emission. At very low frequencies (VLF), auroral hiss has previously been detected at conjugate observatories in Iceland and Antarctica, and satellite-borne radio receivers have observed AKR simultaneously emanating from conjugate sources; however, the other types of radio emission have never been studied at both ends of a magnetic field line. To accomplish this, LF/MF/HF radio receivers have recently been installed at Qikiktarjuaq and Iqaluit, Nunavut, observatories of the Canadian High Arctic Ionospheric Network (CHAIN) which straddle the nominal magnetic conjugate point of South Pole Station, Antarctica, where Dartmouth College operates LF/MF/HF receivers. The Arctic observations employ a dedicated 10-m^2 magnetic loop antenna with active preamp, and a feed from the horizontal linear dipole antennas used for reception of CHAIN ionosonde signals. The Antarctic observations use magnetic loops of areas 2.5-40 m^2 depending on frequency range. Both systems have collected data since October, 2022. Conjugate auroral hiss events have been detected in both equinoctial and solstice conditions. In the latter case, the hiss observed in the daylit hemisphere was weaker than that in the dark ionosphere. Based on initial data, the characteristics and seasonal dependence of conjugate LF auroral hiss appears consistent with previous observations at VLF. Many hiss and cyclotron harmonic emissions have been observed in one hemisphere but not the other. Upcoming 2023 Spring equinox will bring a period of simultaneous darkness at South Pole and Qikiktarjuaq ideal for conjugate medium frequency burst and cyclotron harmonic emissions.

}, author = {James LaBelle and David McGaw and T. Kovacs and A. Kashcheyev and P.T. Jayachandran} } @proceedings {688, title = {Personal Space Weather Station Central Control and Database System}, year = {2023}, month = {03/2023}, publisher = {HamSCI}, address = {Scranton, PA}, abstract = {

As part of the Personal Space Weather Station (PSWS) project, our team has been developing the Central Control System and Central Database System that will be used to collect and store the data generated by the stations. The Central Control System functionality is being developed using Django, a Python based web framework. It is used to define how users will interact with the web server where their collected data will be uploaded, organized, and analyzed. It is also used to define models for the data being collected and how it will be stored in the Central Database System. In the server{\textquoteright}s current state, users can register accounts and stations as well as view lists of uploaded observations. Observation data can also be downloaded individually for analysis. The availability of the PSWS will allow a much larger sample of data to be collected daily. With this data, more accurate models of the ionosphere can be created, granting a better ability to predict how radio waves will be precisely affected by the ionosphere at any given moment and supporting ionospheric science.

}, author = {Anderson B. Liddle and Nicholas Muscalino and William D. Engleke and Travis Atkison} } @proceedings {757, title = {PyLap: An Open Source Python Interface to the PHaRLAP Ionospheric Raytracing Toolkit}, year = {2023}, month = {03/2023}, publisher = {HamSCI}, address = {Scranton, PA}, abstract = {

PyLap is a Python interface to the ionospheric ray tracing toolkit PHaRLAP. The software allows users to generate accurate models of the ionosphere and ray tracing to make plots of radio propagation through the ionosphere. Not only does this software look, feel, and operate very similarly to how the MATLAB interface is currently used, it is also completely free alternative to the current MATLAB interface.

}, author = {Devin Diehl and Gerard Piccini and Alexander Calderon and Joshua Vega and William Liles and Nathaniel A. Frissell} } @proceedings {611, title = {Allan Deviation Analysis of WWV Doppler Shift Measurements recorded with the HamSCI Grape 1 Receiver}, year = {2022}, month = {03/2022}, publisher = {HamSCI}, address = {Huntsville, AL}, abstract = {

The Allan deviation (ADEV) is a well-established metric, recognized by the IEEE and other standards organizations, for estimating the frequency stability of quartz and atomic oscillators over averaging intervals of varying duration.\  To show that ADEV may also be useful for the analysis of radio path stability, this presentation will apply ADEV analysis to WWV Doppler Shift measurements recorded with the Grape 1 receiver designed by N8OBJ.\  This analysis greatly benefits from the fact that the WWV broadcasts are referenced to an ensemble of atomic oscillators continuously adjusted to agree with Coordinated Universal Time (UTC), and the Grape 1 receiver is referenced to a GPS disciplined oscillator (GPSDO) referenced to atomic oscillators aboard the satellites, that are also in step with UTC.\  Therefore, atomic clock accuracy is always present at both ends of the radio path. This presentation will first describe how ADEV is defined and computed, including a discussion of free software tools that are readily available.\  It will then discuss how everything necessary to compute ADEV can be obtained from the Grape 1 data files.\  It will demonstrate that the small instabilities present in the GPSDO that Grape 1 uses for its reference should be indiscernible in the WWV measurements.\  Finally, the presentation will show annotated ADEV graphs generated from the collected data.\  The presented measurements are predominantly groundwave observations of WWV, recorded at a distance of about 15 km from the station by W0DAS in Fort Collins, Colorado, and at a distance of about 81 km by K0WWX in Broomfield, Colorado.\  However, the same ADEV analysis described here is easily applicable to both groundwave and skywave data.\ 

}, author = {Michael A. Lombardi} } @proceedings {607, title = {AM Broadcast Signals Observed at South Pole}, year = {2022}, month = {03/2022}, publisher = {HamSCI}, address = {Huntsville, AL}, abstract = {

For many years, Dartmouth College has operated radio receivers at the Amundsen-Scott South Pole Station, primarily at 100-5000 kHz (LF through lower HF). The primary purpose is to measure radio noise of natural auroral origin, but beacon and broadcast bands are received as a by-product. South Pole has a unique situation of six months of darkness/daylight; that is, a six month day-night cycle, but a 24-hour magnetic local time cycle. Broadcast band signals are received during the six months of darkness, but the local time dependence determined from low-resolution receivers was always a mystery, exhibiting peaks around both noon and midnight magnetic local time. Recent high resolution observations resolved the mystery, demonstrating that one of these local time peaks consists of Region 1 AM signals on 10-kHz spacings, and the other peak consists of Region 2 signals on 9-kHz spacings. The local time dependence results from the geographical distribution of the sources, combined with the position of the solar terminator. In some cases detailed geographical dependences produce observable propagation effects. The Region 1 signals are received around magnetic midnight and heavily affected by auroral activity, whereas the Region 2 signals are received during daytime aurora and are less variable. These interesting effects provide additional arguments for establishing a space-weather radio receiver at South Pole in the future, though they also argue for taking the effort to install a sufficiently sensitive antenna/pre-amplifier.

}, author = {James LaBelle and Ellie Boyd} } @article {667, title = {Amateur Radio: An Integral Tool for Atmospheric, Ionospheric, and Space Physics Research and Operations}, journal = {White Paper Submitted to the National Academy of Sciences Decadal Survey for Solar and Space Physics (Heliophysics) 2024-2033}, year = {2022}, doi = {10.3847/25c2cfeb.18632d86}, author = {Nathaniel A. Frissell and Laura Brandt and Stephen A. Cerwin and Kristina V. Collins and David Kazdan and John Gibbons and William D. Engelke and Rachel M. Frissell and Robert B. Gerzoff and Stephen R. Kaeppler and Vincent Ledvina and William Liles and Michael Lombardi and Elizabeth MacDonald and Francesca Di Mare and Ethan S. Miller and Gareth W. Perry and Jonathan D. Rizzo and Diego F. Sanchez and H. Lawrence Serra and H. Ward Silver and David R. Themens and Mary Lou West} } @proceedings {623, title = {Broadband Loop Antennas and Preamplifiers for Receiving VLF to HF}, year = {2022}, month = {03/2022}, publisher = {HamSCI}, address = {Huntsville, AL}, abstract = {

Wire loop antennas have been used to receive natural and man-made signals over wide bands from 100kHz to 10MHz.\  This talk will cover size considerations and preamplifier design.

}, author = {David McGaw and Mike Trimpi and James LaBelle} } @article {670, title = {Fostering Collaborations with the Amateur Radio Community}, journal = {White Paper Submitted to the National Academy of Sciences Decadal Survey for Solar and Space Physics (Heliophysics) 2024-2033}, year = {2022}, doi = {10.3847/25c2cfeb.09fe22b4}, author = {Nathaniel A. Frissell and Laura Brandt and Stephen A. Cerwin and Kristina V. Collins and Timothy J. Duffy and David Kazdan and John Gibbons and William D. Engelke and Rachel M. Frissell and Robert B. Gerzoff and Stephen R. Kaeppler and Vincent Ledvina and William Liles and Elizabeth MacDonald and Gareth W. Perry and Jonathan D. Rizzo and Diego F. Sanchez and H. Lawrence Serra and H. Ward Silver and Tamitha Mulligan Skov and Mary Lou West} } @proceedings {646, title = {HF Doppler Observations of Traveling Ionospheric Disturbances in a WWV Signal Received with a Network of Low Cost HamSCI Personal Space Weather Stations}, year = {2022}, month = {03/2022}, publisher = {HamSCI}, address = {Huntsville, AL}, abstract = {

Traveling Ionospheric Disturbances (TIDs) are quasi-periodic variations in ionospheric electron density that are often associated with atmospheric gravity waves. TIDs cause amplitude and frequency variations in high frequency (HF, 3 30 MHz) refracted radio waves. The authors present an analysis of observations of TIDs made with Ham Radio Science Citizen Investigation ( HamSCI ) Low Cost Personal Space Weather Stations (PSWS) located in Northwestern New Jersey and near Cleveland, Ohio. The TIDs were detected in the Doppler shifted carrier of the received signal from the 10 MHz WWV frequency and time standard station in Fort Collins, CO. Using a lagged cross correlation analysis, we demonstrate a method for determining TID wavelength, direction, and period using the collected WWV HF Doppler shifted data.

}, author = {Veronica Romanek and Nathaniel A. Frissell and William Liles and John Gibbons and Kristina V. Collins} } @proceedings {650, title = {Magnetosphere-Ionosphere Coupling Studies Using the PSWS Magnetometer Network}, year = {2022}, month = {03/2022}, publisher = {HamSCI}, address = {Huntsville, AL}, abstract = {

As part of HamSCI Personal Space Weather Station (PSWS) project, a low-cost, commercial off-the-shelf magnetometer, which measures magnetic field strength and direction, has been developed to provide quantitative and qualitative measurements of the geospace environment from the ground for both scientific and operational purposes at a cost that will allow for crowd-sourced data contributions. The PSWS magnetometers employ a magneto-inductive sensor technology to record three-axis magnetic field variations with a field resolution of ~6 nT at a 1 Hz sample rate. Data from the PSWS network will combine these magnetometer measurements with high frequency (HF, 3-30 MHz) radio observations to monitor large-scale current systems and ionospheric disturbances due to drivers from both space and the atmosphere. A densely-spaced magnetometer array, once established, will demonstrate their space weather monitoring capability to an unprecedented spatial extent. Magnetic field data obtained by the magnetometers installed at various locations in the US are presented and compared with the existing magnetometers nearby, demonstrating that its performance is very adequate for scientific investigations.

}, author = {Hyomin Kim and Sadaf Ansari and Julius Madey and David Witten and David Larsen and Scotty Cowling and Nathaniel Frissell and James Weygand} } @proceedings {614, title = {The North Dakota Dual Aurora Camera (NoDDAC), A Student-led Citizen Science Project: Data Showcase, Future Developments, and Scientific Potential}, year = {2022}, month = {03/2022}, publisher = {HamSCI}, address = {Huntsville, AL}, abstract = {

The North Dakota Dual Aurora Camera (NoDDAC) is a student-led project in collaboration with the University of North Dakota (UND), Live Aurora Network, and Aurorasaurus. Aurora cameras provide ground-truth visual data to aurora chasers and scientists, but are sparse at midlatitudes. Deploying a light-sensitive video camera and allsky still camera in these areas provides a valuable resource to aurora-chasing communities, including ham radio operators in the auroral zone, and demonstrates scientific merit. For example, the analysis of rare phenomena benefits from observations at multiple locations. In addition, NoDDAC data can be correlated with radio and ionospheric propagation changes, as well as geomagnetic activity, to investigate the connection between optical aurora and radio science. This project is unique; utilizing dual cameras with COTS equipment, emphasizing open data as a responsive community resource, and promoting citizen science make it an accessible resource benefing multiple audiences. Since early 2021, NoDDAC has detected aurora on more than 20 occasions, as well as unusual events like overhead auroras, STEVEs, and noctilucent clouds.\ 

NoDDAC is stationed at Martens Observatory (48.1{\textdegree}N), which is operated by the UND Department of Physics and Astrophysics. Live Aurora Network housings weatherproof both cameras, and their proprietary IPTimelapse software uploads images to a web server for analysis. The north-facing camera records video, allowing Zooniverse-style citizen science for small auroral features. Live Aurora Network streams both cameras on their website and app. Ultimately, when aurora is detected IPTimelapse will post a clip of the display to @NODDAC_cameras on Twitter. Automated reports will be mapped on Aurorasaurus, alongside citizen scientist observations. Image data are archived according to open source and FAIR data principles. NoDDAC will also look for crossovers with projects such as the Personal Space Weather Station to provide additional ground-based measurements of the space environment. This presentation will reflect on the data captured with NoDDAC and outline a timeline for its future, and open the floor for collaborations with other citizen science efforts.

}, author = {Vincent Ledvina and Elizabeth MacDonald and Laura Brandt and Michael McCormack and Steve Collins and Wayne Barkhouse and Timothy Young} } @proceedings {636, title = {Porting the MUSIC Algorithm to the SuperDARN pyDARN Library for the Study of Traveling Ionospheric Disturbances}, year = {2022}, month = {03/2022}, publisher = {HamSCI}, address = {Huntsville, AL}, abstract = {

Medium Scale Traveling Ionospheric Disturbances (MSTIDs) are quasi-periodic variations of the F-region ionosphere with periods of 15 to 60 minutes and horizontal wavelengths of a few hundred kilometers that are often associated with atmospheric gravity waves (AGWs). Understanding differences in characteristics such as wavelength, period, and propagation direction between MSTIDs populations in the northern and southern hemisphere can lead to a better understanding of MSTID sources and upper atmospheric dynamics. Previous studies have used SuperDARN radars to observe MSTIDs and determine these characteristics using an implementation of the multiple signal classification (MUSIC) algorithm. In this presentation, we port the MUSIC implementation written in Python 2 for use with the deprecated SuperDARN Data and Visualization Toolkit python (DaViTpy) to Python 3 for use with the current pyDARN library. This implementation will be used to study the differences between MSTID populations observed by SuperDARN radars in both the Northern and Southern hemispheres.

}, author = {Francis Tholley and Nathaniel A. Frissell and William Liles} } @proceedings {635, title = {Preliminary Analysis of WWV Experimental Tone Signals}, year = {2022}, month = {03/2022}, publisher = {HamSCI}, address = {Huntsville, AL}, abstract = {

NIST Time station WWV and WWVH have recently been broadcasting a set of audio modulation signals designed by the WWV/H Scientific Modulation Group as an initial exploration of possibilities for using these powerful and ubiquitous time distribution HF transmissions as remote sensing diagnostics of the terrestrial ionosphere.\  Included audio modulations include pseudorandom white noise, swept chirps, controlled amplitude sequences, and single pulses.\  The first task in assessing feasibility for remote sensing is to analyze characteristics of the analog WWV transmitters themselves, in order to gauge the transfer function imposed on the original test transmission.\  Using ground wave recordings from a GNSS locked receiver station maintained by Glenn Elmore N6GN, we present preliminary transmitter-centric analysis of WWV experimental tone signals, focusing on amplitude fidelity, transmission delay, cross-ambiguity examination of frequency and amplitude stability, and pseudorandom noise determinations of audio passband shape.

}, author = {Ethan S. Miller and William Liles and Philip J Erickson} } @proceedings {641, title = {Ray Tracing in Python Utilizing the PHaRLAP Engine}, year = {2022}, month = {03/2022}, publisher = {HamSCI}, address = {Huntsville, AL}, abstract = {

Provision of High-Frequency Raytracing Laboratory for Propagation (PHaRLAP) is an ionospheric ray tracing library developed by the Australian Department of Defence (DOD). PHaRLAP is freely available as a MATLAB toolbox downloadable from an Australian DOD website. PHaRLAP is capable of numerically ray tracing radio propagation paths using 2D and 3D algorithms through model ionospheres, most typically the International Reference Ionosphere (IRI). In an effort to make PHaRLAP available to a wider user community we are porting the PHaRLAP MATLAB toolbox to the open source Python 3 language while retaining the original core PHaRLAP computational engine. In this presentation, we describe the architecture of the new Python 3 PHaRLAP interface and demonstrate examples of 2D ray traces using the new interface.

}, author = {Alexander Calderon and William Liles and Nathaniel Frissell and Joshua Vega} } @proceedings {575, title = {Climatology of Traveling Ionospheric Disturbances Observed by HamSCI Amateur Radio with Connections to Geospace and Neutral Atmospheric Sources}, year = {2021}, month = {09/2021}, publisher = {ARRL-TAPR}, address = {Virtual}, url = {https://youtu.be/MHkz7jNynOg?t=23773}, author = {Sanchez, Diego F. and Frissell, Nathaniel A. and Perry, Gareth W. and Engelke, William D. and Coster, Anthea J. and Erickson, Philip J. and Ruohoniemi, J. Michael and Baker, Joseph B. H. and Harvey, Lynn and Luetzelschwab, R. Carl} } @conference {557, title = {Early Results from the Ionospheric Sounding Mode Using Chirp Ionosondes of Opportunity for the HamSCI Personal Space Weather Station}, booktitle = {2021 XXXIVth General Assembly and Scientific Symposium of the International Union of Radio Science (URSI GASS)}, year = {2021}, abstract = {

The objective of the Ham Radio Science Citizen Investigation (HamSCI) Personal Space Weather Station (PSWS) project is to develop a distributed array of ground-based multi-instrument nodes capable of remote sensing the geospace system. This system is being designed with the intention of distribution to a large number of amateur radio and citizen science observers. This will create an unprecedented opportunity to probe the ionosphere at finer resolution in both time and space as all measurements will be collected into a central database for coordinated analysis. Individual nodes are being designed to service the needs of the professional space science researcher while being cost-accessible and of interest to amateur radio operators and citizen scientists. At the heart of the HamSCI PSWS will be a high performance 0.1{\textendash}60 MHz software defined radio (SDR) [1] with GNSS-based precision timestamping and frequency reference. This SDR is known as the TangerineSDR and is being developed by the Tucson Amateur Packet Radio (TAPR) amateur radio organization. The primary objective of PSWS system is to gather observations to understand the short term and small spatial scale ionospheric variabilities in the ionosphere-thermosphere system. These variabilities are important for understanding a variety of geophysical phenomena such as Traveling Ionospheric Disturbances (TIDs) [2], Ionospheric absorption events, geomagnetic storms and substorms. We present early results suggesting signature of Traveling Ionospheric Disturbances (TIDs) from an ionospheric sounding mode that we intend to implement on the PSWS system, currently implemented on an Ettus N200 Universal Software Radio Peripheral (USRP) using the open source GNU Chirpsounder data collection and analysis code.

}, doi = {10.23919/URSIGASS51995.2021.9560441}, author = {Joshi, Dev and Frissell, Nathaniel and Liles, William and Vierinen, Juha and Miller, Ethan S.} } @conference {544, title = {HamSCI Personal Space Weather: Architecture and Applications to Radio Astronomy}, booktitle = {Annual (Summer) Eastern Conference}, year = {2021}, month = {07/2021}, publisher = {Society of Amateur Radio Astronomers (SARA)}, organization = {Society of Amateur Radio Astronomers (SARA)}, address = {Virtual}, abstract = {

The Ham Radio Science Citizen Investigation (HamSCI) Personal Space Weather Station (PSWS) project is a citizen science initiative to develop a new modular set of ground-based instrumentation for the purpose of studying the structure and dynamics of the terrestrial ionosphere, as well as the larger, coupled geospace system. PSWS system instrumentation includes radio receivers sensitive to frequencies ranging from the very low frequency (VLF) through very high frequency (VHF) bands, a Global Navigation Satellite System (GNSS) receiver to provide Total Electron Content (TEC) measurements and serve as a precision time and frequency reference, and a ground magnetometer sensitive to ionospheric and geospace currents. Although the PSWS is designed primarily for space weather and space science, its modular and open design in both hardware and software allows for a variety of use cases. The core radio instrument of the PSWS, the TangerineSDR, is a wideband, direct sampling 100~kHz to 60~MHz field programmable gate array (FPGA)-based software defined radio (SDR) receiver with direct applicability to radio astronomy. In this paper, we describe the PSWS and TangerineSDR architecture, show examples of how the TangerineSDR could be used to observe Jovian decametric emission, and discuss the applicability of the TangerineSDR to radio astronomy in general.

}, url = {https://rasdr.org/store/books/books/journals/proceedings-of-annual-conference}, author = {Nathaniel A. Frissell and Scott H. Cowling and Thomas C. McDermott and John Ackermann and David Typinski and William D. Engelke and David R. Larsen and David G. McGaw and Hyomin Kim and David M. Witten, II and Julius M. Madey and Kristina V. Collins and John C. Gibbons and David Kazdan and Aidan Montare and Dev Raj Joshi and Veronica I. Romanek and Cuong D. Nguyen and Stephen A. Cerwin and William Liles and Jonathan D. Rizzo and Ethan S. Miller and Juha Vierinen and Philip J. Erickson and Mary Lou West} } @conference {540, title = {HamSCI Personal Space Weather Station (PSWS): Architecture and Current Status}, booktitle = {NSF CEDAR (Coupling, Energetics, and Dynamics of Atmospheric Regions)}, year = {2021}, month = {06/2021}, publisher = {CEDAR}, organization = {CEDAR}, address = {Virtual}, abstract = {

Recent advances in geospace remote sensing have shown that large-scale distributed networks of ground-based sensors pay large dividends by providing a big picture view of phenomena that were previously observed only by point-measurements. While existing instrument networks provide excellent insight into ionospheric and space science, the system remains undersampled and more observations are needed to advance understanding. In an effort to generate these additional measurements, the Ham Radio Science Citizen Investigation (HamSCI, hamsci.org) is working with the Tucson Amateur Packet Radio Corporation (TAPR, tapr.org), an engineering organization comprised of volunteer amateur radio operators and engineers, to develop a network of Personal Space Weather Stations (PSWS). These instruments that will provide scientific-grade observations of signals-of-opportunity across the HF bands from volunteer citizen observers as part of the NSF Distributed Array of Small Instruments (DASI) program. A performance-driven PSWS design (~US$500) will be a modular, multi-instrument device that will consist of a dual-channel phase-locked 0.1-60 MHz software defined radio (SDR) receiver, a ground magnetometer with (~10 nT resolution and 1-sec cadence), and GPS/GNSS receiver to provide precision time stamping and serve as a GPS disciplined oscillator (GPSDO) to provide stability to the SDR receiver. A low-cost PSWS (\< US$100) that measures Doppler shift of HF signals received from standards stations such as WWV (US) and CHU (Canada) and includes a magnetometer is also being developed. HF sounding algorithms making use of signals of opportunity will be developed for the SDR-based PSWS. All measurements will be collected into a central database for coordinated analysis and made available for public access.

}, author = {Nathaniel A. Frissell and Dev Joshi and Veronica I. Romanek and Kristina V. Collins and Aidan Montare and David Kazdan and John Gibbons and William D. Engelke and Travis Atkison and Hyomin Kim and Scott H. Cowling and Thomas C. McDermott and John Ackermann and David Witten and Julius Madey and H. Ward Silver and William Liles and Steven Cerwin and Philip J. Erickson and Ethan S. Miller and Juha Vierinen} } @proceedings {561, title = {HamSCI Personal Space Weather Station (PSWS): Fall 2021 Update}, year = {2021}, month = {09/2021}, publisher = {ARRL-TAPR}, address = {Virtual}, url = {https://youtu.be/MHkz7jNynOg?t=1990}, author = {Frissell, Nathaniel A. and Joshi, Dev Raj and Collins, Kristina and Montare Aidan and Kazdan, David and Engelke, William D. and Atkison, Travis and Kim, Hyomin and Cowling, Scott H. and McDermott, Thomas C. and Ackermann, John and Witten, David and Madey, Jules and Silver, H. Ward and Liles, W. and Cerwin, Stephen A. and Erickson, Phillip J. and Miller, Ethan S, and Vierinen, Juha} } @conference {539, title = {HF Doppler Observations of Traveling Ionospheric Disturbances in a WWV Signal Received with a Network of Low-Cost HamSCI Personal Space Weather Stations}, booktitle = {NSF CEDAR (Coupling, Energetics, and Dynamics of Atmospheric Regions)}, year = {2021}, month = {06/2021}, publisher = {CEDAR}, organization = {CEDAR}, address = {Virtual}, abstract = {

Traveling Ionospheric Disturbances (TIDs) are quasi-periodic variations in ionospheric electron density that are often associated with atmospheric gravity waves. TIDs cause amplitude and frequency variations in high frequency (HF, 3-30 MHz) refracted radio waves. We present observations of TIDs made with a network of Ham Radio Science Citizen Investigation (HamSCI) Low-Cost Personal Space Weather Stations (PSWS) with nodes located in Pennsylvania, New Jersey, and Ohio. The TIDs were detected in the Doppler shifted carrier of the received signal from the 10 MHz WWV frequency and time standard station in Fort Collins, CO. Using a lagged cross correlation analysis, we demonstrate a method for determining TID wavelength, direction, and period using the collected WWV HF Doppler shifted data.

}, author = {Veronica I. Romanek and Nathaniel A. Frissell and Dev Joshi and William Liles and Clair Trop and Kristina Collins and Gareth Perry} } @conference {545, title = {HF Doppler Observations of Traveling Ionospheric Disturbances in a WWV Signal Received with a Network of Low-Cost HamSCI Personal Space Weather Stations}, booktitle = {Annual (Summer) Eastern Conference}, year = {2021}, month = {07/2021}, publisher = {Society of Amateur Radio Astronomers (SARA)}, organization = {Society of Amateur Radio Astronomers (SARA)}, address = {Virtual}, abstract = {

Traveling Ionospheric Disturbances (TIDs) are quasi-periodic variations in ionospheric electron density that are often associated with atmospheric gravity waves. TIDs cause amplitude and frequency variations in high frequency (HF, 3-30 MHz) refracted radio waves. One way to detect TIDs is through the use of a Grape Personal Space Weather Station (PSWS). The Grape PSWS successfully detected TIDs in the Doppler shifted carrier of the received signal from the 10 MHz WWV frequency and time standard station in Fort Collins, CO. This paper will present an explanation of how the Grape PSWS was used to collect data, and how scientist can use this data to further investigate the ionosphere.

}, url = {https://rasdr.org/store/books/books/journals/proceedings-of-annual-conference}, author = {Veronica I. Romanek and Nathaniel A. Frissell and Dev Raj Joshi and William Liles and Claire C. Trop and Kristina V. Collins and Gareth W. Perry} } @proceedings {578, title = {HF Doppler Observations of Traveling Ionospheric Disturbances in the WWV Signal Received with a Network of Low-Cost HamSCI Personal Space Weather Stations}, year = {2021}, month = {09/2021}, publisher = {ARRL-TAPR}, address = {Virtual}, url = {https://youtu.be/kVY3E3e--_I?t=3495}, author = {Romanek, Veronica I. and Frissell, Nathaniel A. and Joshi, Dev Raj and Liles, William and Trop, Claire and Collins, Kristina and Perry, Gareth W.} } @conference {580, title = {HF Doppler Observations of Traveling Ionospheric Disturbances in the WWV Signal Received with a Network of Low-Cost HamSCI Personal Space Weather Stations}, booktitle = {American Geophysical Union Fall Meeting}, year = {2021}, month = {12}, publisher = {American Geophysical Union}, organization = {American Geophysical Union}, address = {New Orleans, LA}, abstract = {

Traveling Ionospheric Disturbances (TIDs) are quasi-periodic variations in ionospheric electron density that are often associated with atmospheric gravity waves. TIDs cause amplitude and frequency variations in high frequency (HF, 3-30 MHz) refracted radio waves. We present observations of TIDs made with a network of Ham Radio Science Citizen Investigation (HamSCI) Low-Cost Personal Space Weather Stations (PSWS) with nodes located in Pennsylvania, New Jersey, and Ohio. The TIDs were detected in the Doppler shifted carrier of the received signal from the WWV frequency and time standard station near Fort Collins, CO. Using a lagged cross correlation analysis, we demonstrate a method for determining TID wavelength, direction, and period using the collected WWV HF Doppler shifted data.

}, url = {https://agu.confex.com/agu/fm21/meetingapp.cgi/Paper/888443}, author = {Romanek, Veronica I. and Frissell, Nathaniel A. and Joshi, Dev Raj and Liles, William and Trop, Clair and Collins, Kristina and Perry, Gareth W.} } @proceedings {458, title = {Mid-latitude Irregularities in the Early Results from the Ionospheric Sounding Mode Using Chirp Ionosondes of Opportunity for the HamSCI Personal Space Weather Station}, year = {2021}, month = {03/2021}, publisher = {HamSCI}, address = {Scranton, PA (Virtual)}, abstract = {

The objective of the Ham Radio Science Citizen Investigation (HamSCI) Personal Space Weather Station (PSWS) project is to develop a distributed array of ground-based multi-instrument nodes capable of remote sensing the geospace system. This system is being designed with the intention of distribution to a large number of amateur radio and citizen science observers. This will create an unprecedented opportunity to probe the ionosphere at finer resolution in both time and space as all measurements will be collected into a central database for coordinated analysis. Individual nodes are being designed to service the needs of the professional space science researcher while being cost-accessible and of interest to amateur radio operators and citizen scientists. At the heart of the HamSCI PSWS will be a high performance 1 {\textendash} 50 MHz software defined radio (SDR) with GNSS-based precision timestamping and frequency reference. This SDR is known as the TangerineSDR and is being developed by the Tucson Amateur Packet Radio (TAPR) amateur radio organization. The primary objective of PSWS system is to gather observations to understand the short term and small spatial scale ionospheric variabilities in the ionosphere-thermosphere system. These variabilities are important for understanding a variety of geophysical phenomena such as Traveling Ionospheric Disturbances (TIDs), Ionospheric absorption events, geomagnetic storms and substorms. We present early results suggesting signatures of Traveling Ionospheric Disturbances (TIDs) from an ionospheric sounding mode that we intend to implement on the PSWS system, currently implemented on an Ettus N200 Universal Software Radio Peripheral (USRP) using the open source GNU Chirpsounder data collection and analysis code.

}, author = {Dev Joshi and Nathaniel A. Frissell and William Liles and Juha Vierinen and Ethan S. Miller} } @conference {536, title = {Observations of Mid-latitude Irregularities Using the Oblique Ionosonde Sounding Mode for the HamSCI Personal Space Weather Station}, booktitle = {NSF CEDAR (Coupling, Energetics, and Dynamics of Atmospheric Regions)}, year = {2021}, month = {06/2021}, publisher = {CEDAR}, organization = {CEDAR}, address = {Virtual}, abstract = {

The spread in the echoes of high-frequency (HF, 3-30 MHz) radio waves from the F-region of the ionosphere has been the earliest indication of plasma density irregularities in the mid-latitude F region ionosphere. Although mid-latitude spread F has been widely studied, the plasma instability mechanisms for these irregularities are still largely unknown. This phenomenon can cause radio wave scintillation effects that degrade the performance of man-made technologies such as satellite communications and global navigation satellite systems (GNSS). Understanding these irregularities so that they can be anticipated and mitigated are important aspects of space weather research. The occurrence climatology and variability can also be helpful in modeling efforts of these irregularities. Here, we present signatures of mid-latitude irregularities observed in oblique ionograms received near Scranton, PA transmitted by the Relocatable Over-the-Horizon Radar (ROTHR) in Chesapeake, Virginia. These observations are collected with the GNU Chirpsounder2 software, an open-source software package capable of creating ionograms from frequency modulated (FM) chirp ionosondes. This ionospheric sounding mode will be implemented in the currently under development Ham Radio Science Citizen Investigation (HamSCI) Personal Space Weather Station (PSWS), a ground-based multi-instrument system designed to remote-sense the ionosphere using signals of opportunity.

}, author = {Dev Joshi and Nathaniel A. Frissell and William Liles and Juha Vierinen} } @proceedings {577, title = {Observations of Mid-latitude Irregularities Using the Oblique Ionosonde Sounding Mode for the HamSCI Personal Space Weather Station (Proceedings)}, year = {2021}, month = {09/2021}, publisher = {ARRL-TAPR}, address = {Virtual}, url = {https://youtu.be/kVY3E3e--_I?t=2542}, author = {Joshi, Dev Raj and Frissell, Nathaniel A. and Liles, William and Vierinen, Juha} } @conference {585, title = {Observations of Mid-latitude Irregularities Using the Oblique Ionosonde Sounding Mode for the HamSCI Personal Space Weather Station}, booktitle = {American Geophysical Union Fall Meeting}, year = {2021}, month = {12}, publisher = {American Geophysical Union}, organization = {American Geophysical Union}, address = {New Orleans, LA}, abstract = {

The spread in the echoes of high-frequency (HF, 3-30 MHz) radio waves from the F-region of the ionosphere was one of the earliest indications of plasma density irregularities in the mid-latitude F region ionosphere. Although mid-latitude spread F has been widely studied, the plasma instability mechanisms that create these irregularities are still largely unknown. This phenomenon can cause radio wave scintillation effects that degrade the performance of human-made technologies such as satellite communications and Global Navigation Satellite Systems (GNSS). Understanding these irregularities so that they can be anticipated and mitigated are important aspects of space weather research. The occurrence climatology and variability can also be helpful in validating models of these irregularities. Here, we present signatures of mid-latitude irregularities observed in oblique ionograms received near Scranton, PA transmitted by the Relocatable Over-the-Horizon Radar (ROTHR) in Chesapeake, Virginia. These observations are collected with the GNU Chirpsounder2 software, an open source software package capable of creating ionograms from frequency modulated (FM) chirp ionosondes. This ionospheric sounding mode will be implemented in the currently under-development Ham Radio Science Citizen Investigation (HamSCI) Personal Space Weather Station (PSWS), a ground-based multi-instrument system designed to remote-sense the ionosphere using signals of opportunity. Using the data from the oblique ionograms, we generate the Range Time Intensity (RTI) plots that show ionospheric dynamics through measured path length variations as a function of time. We also compare the RTI plots with Range-Time-Parameter (RTP) plots from the SuperDARN HF radar in Blackstone, Virginia which commonly observes direct backscatter from decameter-scale irregularities within the region of ionosphere traversed by the ROTHR signal.

}, url = {https://agu.confex.com/agu/fm21/meetingapp.cgi/Paper/875589}, author = {Joshi, Dev Raj and Frissell, Nathaniel A. and Sarwar, M. Shaaf and Sami, Simal and Ruohoniemi, J. Michael and Baker, Joseph B. H. and Coster, Anthea J. and Erickson, Philip J. and Liles, William and Vierinen, Juha and Groves, Keith} } @proceedings {460, title = {Preliminary Data Analysis of PSWS Magnetometer Data}, year = {2021}, month = {03/2021}, publisher = {HamSCI}, address = {Scranton, PA (Virtual)}, abstract = {

We report on the preliminary analysis of data obtained from newly developed magnetometers as part of HamSCI Personal Space Weather Station (PSWS) project. These systems are designed to provide quantitative and qualitative measurements of the geospace environment from the ground for both scientific and operational purposes at a cost that will allow for crowd-sourced data contributions. The PSWS magnetometers employ low-cost, commercial off-the-shelf, magneto-inductive sensor technology to record three-axis magnetic field variations with an adequate field resolution of ~10 nT at a 1 Hz sample rate. Data from the PSWS network will combine these magnetometer measurements with high frequency (HF, 3-30 MHz) radio observations to monitor large-scale current systems and ionospheric disturbances due to drivers from both space and the atmosphere. A densely-spaced magnetometer array, once established, will demonstrate their space weather monitoring capability in unprecedented spatial extent. Magnetic field data obtained by the magnetometers installed at three locations across the US are presented and compared with the existing magnetometers nearby.\ 

}, author = {Hyomin Kim and Julius Madey and David M. Witten II and David Larsen and Scott H. Cowling and Nathaniel A. Frissell and James Weygand} } @proceedings {500, title = {PSWS Ground Magnetometer Hardware}, year = {2021}, month = {03/2021}, publisher = {HamSCI}, address = {Scranton, PA (Virtual)}, abstract = {

The path from candidate device for the magnetometer function of the PSWS to practical affordable working 24/7 data collection installations based on the low cost and readily available PNI RM3100 magneto-inductive sensor is discussed.\  Initial support board design using i2c bus connection to the host Odroid or Raspberry Pi class microprocessors with support for remote extension of the sensor to at least 100 feet with common CAT5 networking cable will be described as well as the accompanying test and logging software.\  Details of initial testing which revealed the need for temperature stabilization of the RM3100, verified remote operation to at least 500 feet, the subsequent design of an in-ground sensor housing made from common PVC water pipe and fittings and refinement of the microprocessor adapter board and remote board will be presented.

}, author = {Julius Madey and David Witten, II and Hyomin Kim and David Larsen and Scott H. Cowling and Nathaniel A. Frissell} } @proceedings {563, title = {PSWS Magnetometer Science Update}, year = {2021}, month = {09/2021}, publisher = {ARRL-TAPR}, address = {Virtual}, url = {https://youtu.be/MHkz7jNynOg?t=4555}, author = {Kim, Hyomin and Madey, Julius and Witten, David and Larsen, David R. and Cowling, Scott H. and Frissell, Nathaniel A. and Weygand, James} } @proceedings {556, title = {Simultaneous observations of mid-latitude Ionospheric Irregularities in HamSCI Personal Space Weather Station and SuperDARN radar}, year = {2021}, month = {05/2021}, publisher = {SANSA}, address = {Virtual}, url = {https://www.sansa.org.za/events-outreach/superdarn-workshop-2021/}, author = {Joshi, Dev Raj and Frissell, Nathaniel A. and Liles, William and Vierinen, Juha} } @proceedings {478, title = {A Survey of HF Doppler TID Signatures Observed Using a Grape in New Jersey}, year = {2021}, month = {03/2021}, publisher = {HamSCI}, address = {Scranton, PA (Virtual)}, url = {https://hamsci2021-uscranton.ipostersessions.com/?s=6A-B6-94-74-A1-46-CF-D2-AC-BA-F3-58-2E-71-17-97}, author = {Veronica I. Romanek and Nathaniel A. Frissell and Dev Joshi and William Liles and Kristina Collins and John Gibbons and David Kazdan} } @proceedings {505, title = {Survey of ionospheric F2 region variability from the lower atmosphere: drivers and responses - Part 1}, year = {2021}, month = {03/2021}, abstract = {

Carl Luetzelschwab, K9LA, will review the factors that cause the F2 region of the ionosphere to vary in the short-term, on day-to-day and even shorter time scales. These factors can directly affect amateur radio operators through their influence on electron density and therefore on HF propagation. Ionospheric variability drivers will be sorted into three broad categories: 1) solar radiation 2) geomagnetic activity and 3) meteorological sources (neutral atmosphere). Carl will also assess how much F2 ionospheric parameters vary in the short-term during both day and night, and he will also review the contribution of each of the factors to observed F2 region variability.

}, author = {R. Carl Luetzelschwab and Philip J. Erickson} } @proceedings {506, title = {Survey of ionospheric F2 region variability from the lower atmosphere: drivers and responses - Part 2}, year = {2021}, month = {03/2021}, publisher = {HamSCI}, address = {Scranton, PA (Virtual)}, abstract = {

Phil Erickson, W1PJE, will follow with a condensed summary of recent community research on the types of physical processes that produce F2 layer ionospheric variations from waves, heating, and other sources in the lower neutral atmosphere (space weather {\textquotedblleft}from below{\textquotedblright}). Examples will include acoustic waves, gravity waves, planetary waves, TADs (traveling atmospheric disturbances), and their influence on TIDs (travelling ionospheric disturbances). Numerical estimates of the various forcing terms provide a useful gauge of the relative importance and impact of these processes. Phil will close by specifically focusing on estimates of the magnitude of electron density variations in the F2 region of the ionosphere due to earthquake effects. In particular, ionospheric density observations from sources such as the global satellite navigation system (GNSS) allow a quantitative, numerate discussion of earthquake drivers in both time and space dimensions as compared to other known lower atmosphere ionospheric variability drivers.\  Phil will conclude with a discussion of the implications for earthquake associated HF propagation effects in the face of observed day-to-day ionospheric density variability.

}, author = {Philip J. Erickson and R. Carl Luetzelschwab} } @proceedings {464, title = {Traveling ionospheric disturbances tracked through Doppler-shifted AM radio transmissions}, year = {2021}, month = {03/2021}, publisher = {HamSCI}, address = {Scranton, PA (Virtual)}, abstract = {

A comprehensive understanding of the ionosphere is critical for many technologies, particularly those that rely on the propagation of radio waves. This study shows that traveling ionospheric disturbances (TIDs), dawn and dusk signal divergence (terminators), and spread F\ can be tracked and analyzed using clear channel AM radio transmissions and a set of geographically distributed receivers. Early attempts by our research group to track TIDs by AM radio signals reflected from the F region of the ionosphere generated results in conflict with those derived from GPS/TEC mapping methods [Chilcote et al., 2015]. This study seeks to resolve those conflicts with a more sophisticated array of receivers spread throughout the northeastern United States. Specifically, the receivers form a ring around an 810 kHz AM radio station in Schenectady, New York. A minimum of four receivers have been operational from 3/19/20 to the present and Doppler-shifted signals, attributed to TID events, have been consistently visible across several radio channels with frequencies between 800 to 1600kHz. We have focused our study thus far on the terminator signals which appear to be consistent with photochemistry effects and on TID wave characteristic analysis. We have collected a set of exceptional TID events over the past nine months and have correlated our calculated wave characteristics with the data from GNSS TEC, digisonde, and SuperDARN in general finding good agreement between our technique and these established methods. While our study still seeks to clarify discrepancies in our data similar to those seen by Chilcote in the original study, the consistency with which our data typically agrees with other methods supports the validity of using AM radio transmissions to track TIDs in addition to other ionospheric phenomena such as the terminator.\ 

Reference: Chilcote, M., et al. (2015), Detection of traveling ionospheric disturbances by medium-frequency Doppler sounding using AM radio transmissions, Radio Sci., 50, doi:10.1002/2014RS005617.

}, author = {Claire C. Trop and James LaBelle and Philip J. Erickson and Shunrong Zhang and David McGaw and Terrence Kovacs} } @proceedings {494, title = {W3USR and The Great Collegiate Shortwave Listening Contest}, year = {2021}, month = {03/2021}, publisher = {HamSCI}, address = {Scranton, PA (Virtual)}, url = {https://hamsci2021-uscranton.ipostersessions.com/Default.aspx?s=1B-12-5C-9B-5C-AF-F5-8B-AC-62-CD-DD-D5-51-6A-9A}, author = {M. Shaaf Sarwar and Veronica I. Romanek and Thomas Baran and Jonathan Rizzo and Steve Holguin and Jonathan Rizzo and Nathaniel A. Frissell and William Liles and Kristina Collins and David Kazdan} } @conference {381, title = {Amateur digital mode based remote sensing: FT8 use as a radar signal of opportunity for ionospheric characterization}, booktitle = {HamSCI Workshop}, year = {2020}, month = {03/2020}, publisher = {HamSCI}, organization = {HamSCI}, address = {Scranton, PA}, abstract = {

The K1JT / WSJT suite of digital modes for amateur QSOs, provided to the community by Joe Taylor K1JT and Steve Franke K9AN, has revolutionized the use of weak signal HF propagation to carry short digital messages. Traffic on the FT8 mode has become a large fraction of all digital transmissions by amateurs since its introduction in 2017 near solar minimum. FT8 is a 15 second cadence, 8-tone FSK mode using a sophisticated combination of stacked low-density parity coding (LDPC) and cyclical redundancy check (CRC) codes. Combined with a deep search retrieval algorithm that takes advantage of the sparse information for messages within typical QSOs, the effective FT8 communications detection threshold is considerably lower than other traditional modes such as CW.

FT8 signals undergo changes on reception caused by ionospheric refraction. Observational study of this feature opens up compelling avenues for research into the time and space dependent behavior of ionospheric variations. A technique long known to the passive radio remote sensing community involves intercepting transmissions of opportunity and processing them to yield information on reflecting targets on the transmit-to-receive path. We present initial simulations and studies of the use of FT8 in this manner as an ionospheric range-Doppler passive radar, and will discuss the qualities of these signals for crowdsourced upper atmospheric research, including an explanation and examples of their effective range-Doppler ambiguity in typical QSO exchanges. Also discussed will be the particular effectiveness for radar applications of the three Costas array frequency/time synchronization sequences used by FT8 in the start, middle, and at the end of transmissions.

}, author = {P. J. Erickson and W. Liles and E. S. Miller} } @conference {398, title = {Construction of an Aurora Camera in North Dakota to Aid in Citizen Science and Space Weather Applications (ePoster)}, booktitle = {HamSCI Workshop 2020}, year = {2020}, month = {03/2020}, publisher = {HamSCI}, organization = {HamSCI}, address = {Scranton, PA}, abstract = {

We will present plans for a new student-built aurora camera integrated with a public university, local astronomy groups, and Aurorasaurus citizen science. Live aurora cameras are crucial tools for avid skywatchers, aurora chasers, and scientists.\ \ Globally there are hundreds of cameras providing nowcast views of aurora strength, yet in low-latitude areas, especially in the United States, the number of high-quality, live aurora cameras is extremely limited.\ \ The need for aurora camera coverage in mid-latitudes is apparent; not only will it be another resource for amateur astronomers and aurora-watching communities, but the analysis of many transient auroral phenomena such as substorms and STEVEs benefit from multiple geographical observations.\ \ A north-facing camera will be built near Inkster, North Dakota, on the Martens Observatory location (approximately 48.1oN), broadcasting a public live stream of the night sky while simultaneously offloading images to a storage server.\ \ The Sony a7s2 mirrorless camera, a model employed by other live broadcasts such as the LiveAuroraNetwork, will be used in conjunction with a wide-aperture lens for maximum light-gathering ability.\ \  The entire apparatus will be housed in a weatherproof enclosure and internet will be supplied on-site.\ \ The camera will be integrated with the University of North Dakota{\textquoteright}s Astrophysics and Space Studies department and will be a resource for the local astronomy community, the Northern Sky Astronomical Society.\ \ Working with Aurorasaurus, the aurora camera will {\textquotedblleft}tweet{\textquotedblright} when an aurora is spotted and be shown on the Aurorasaurus auroral oval map along with other citizen scientist observations.\ \ This aurora camera will be a valuable resource for citizen science and will aid scientists in attempting to unravel the mysteries of Earth{\textquoteright}s magnetism.

}, author = {Vincent Ledvina and Elizabeth MacDonald and Wayne Barkhouse and Timothy Young} } @conference {384, title = {EclipseMob: Initial Planning for 2024}, booktitle = {HamSCI Workshop}, year = {2020}, month = {03/2020}, publisher = {HamSCI}, organization = {HamSCI}, address = {Scranton, PA}, abstract = {

During the lead up to the 2017 Solar Eclipse and its aftermath, the EclipseMob team learned many things about crowdsourcing technology development and data collection. We are taking those lessons along with lessons learned from other crowdsourced citizen science programs to improve the EclipseMob experience for the upcoming 2024 Solar Eclipse. One such lesson is to start planning, building, and recruiting much earlier, and we are. EclipseMob is on schedule to finalize the design and testing of a new receiver system this summer. The 2017 Solar Eclipse collection platform relied on participants{\textquoteright} personal smartphones, which supplied the analog to digital converter (ADC), local oscillator, time, location, web access, and computational power. Our platform for 2024 eliminates the need for a smartphone by using a Raspberry Pi (RPi), analog amplifier, ADC, and GPS, in a self-contained unit. By eliminating the smartphone, the new design standardizes the hardware and increases economic accessibility. The 2024 platform is designed to collect WWVB signals at 60 kHz, as was the 2017 platform, but will also collect signals at lower frequencies such as the US Navy VLF transmitters. Those lower frequencies had to be ignored during the 2017 effort due to the limited bandwidth of the ADC in the smart phones. The construction process for the 2024 receiver kit has been heavily simplified, which we expect will result in increased participant success and satisfaction. In addition to modifying the data collection platform, 2024 EclipseMob is also changing its outreach approach. Instead of the centrally recruiting, training, and supporting participants, EclipseMob is switching to a train the trainer model. The EclipseMob team will work with and train a small subset of community leaders (from schools, libraries, ham radio clubs, etc.) to recruit and support participants locally. This should also increase the geospatial distribution of participants. In 2017 most participants were located in areas near the two main schools involved, which resulted in dense sampling in the Boston, MA and Fairfax, VA area. EclipseMob training materials will continue to meet the standards necessary for teacher continuing education credits and student learning.

}, author = {K. C. Kerby-Patel and L. Lukes and J. Nelson and W. Liles} } @article {428, title = {The Great Collegiate Shortwave Listening Contest}, year = {2020}, author = {Frissell, N. A. and Liles, W. and Collins, K. and Kazdan, D} } @conference {424, title = {HamSCI Distributed Array of Small Instruments Personal Space Weather Station (DASI-PSWS): Architecture and Current Status (Invited)}, booktitle = {NSF CEDAR (Coupling, Energetics, and Dynamics of Atmospheric Regions)}, year = {2020}, month = {06/2020}, address = {Santa Fe, NM (Virtual)}, abstract = {

Recent advances in geospace remote sensing have shown that large-scale distributed networks of ground-based sensors pay large dividends by providing a big picture view of phenomena that were previously observed only by point-measurements. While existing instrument networks provide excellent insight into ionospheric and space science, the system remains undersampled and more observations are needed to advance understanding. In an effort to generate these additional measurements, the Ham Radio Science Citizen Investigation (HamSCI, hamsci.org) is working with the Tucson Amateur Packet Radio Corporation (TAPR, tapr.org), an engineering organization comprised of volunteer amateur radio operators and engineers, to develop a network of Personal Space Weather Stations (PSWS). These instruments that will provide scientific-grade observations of signals-of-opportunity across the HF bands from volunteer citizen observers as part of the NSF Distributed Array of Small Instruments (DASI) program. A performance-driven PSWS design (~US$500) will be a modular, multi-instrument device that will consist of a dual-channel phase-locked 0.1-60 MHz software defined radio (SDR) receiver, a ground magnetometer with (~10 nT resolution and 1-sec cadence), and GPS/GNSS receiver to provide precision time stamping and serve as a GPS disciplined oscillator (GPSDO) to provide stability to the SDR receiver. A low-cost PSWS (\< US$100) that measures Doppler shift of HF signals received from standards stations such as WWV (US) and CHU (Canada) and includes a magnetometer is also being developed. HF sounding algorithms making use of signals of opportunity will be developed for the SDR-based PSWS. All measurements will be collected into a central database for coordinated analysis and made available for public access.

}, url = {http://cedarweb.vsp.ucar.edu/wiki/index.php/2020_Workshop:MainVG}, author = {N. A. Frissell and D. Joshi and K. Collins and A. Montare and D. Kazdan and J. Gibbons and S. Mandal and W. Engelke and T. Atkison and H. Kim and A. J. Gerrard and J. S. Vega and S. H. Cowling and T. C. McDermott and J. Ackermann and D. Witten and H. W. Silver and W. Liles and S. Cerwin and P. J. Erickson and E. S. Miller} } @conference {359, title = {HamSCI: Space Weather Operational Resources and Needs of the Amateur Radio Community}, booktitle = {American Meteorological Society Annual Meeting}, year = {2020}, month = {01/2020}, publisher = {American Meteorological Society Annual Meeting}, organization = {American Meteorological Society Annual Meeting}, address = {Boston, MA}, abstract = {

The amateur (ham) radio community is a global community of over 3 million people who use and build radio equipment for communications, experimentation, and science. By definition, amateur radio is a volunteer service, with the operators required to hold government-issued licenses that are typically earned by passing knowledge tests covering radio regulations and practices, radio theory, and electromagnetic theory. In the United States, there are about 750,000 licensed hams, ranging in age from very young to very old, and ranging in experience from neophyte to people with advanced degrees in radio engineering and science. Amateur radio operators are licensed to transmit on bands spread across the radio frequency (RF) spectrum, from very low frequency (VLF) up to hundreds of gigahertz. The purpose of these communications range from mission-critical emergency and public service communications to social contacts to highly competitive contests and achievement award programs. Many of these communications rely on trans-ionospheric paths, and therefore are heavily influenced by conditions in near-Earth space, or space weather.
Amateurs today obtain space weather and propagation prediction information from sources such as the NOAA Space Weather Prediction Center (SWPC), spaceweather.com, the Voice of America Coverage Analysis Program (VOACAP), amateur radio propagation columnists (ARRL, RSGB, and CQ Magazine), and spaceweatherwoman.com (Dr. Tamitha Skov). In order to predict success for their communications efforts, hams often use parameters such as smoothed sunspot number, 10.7 cm wavelength solar flux proxy, and the planetary Kp and Ap indices as inputs to predict radio propagation performance. Traditionally, these predictions focus on the driving influence of space conditions and the sun{\textquoteright}s output. However, frontier research in the space sciences community has revealed that for improved predictive success, much more information needs to be provided on neutral atmosphere dynamics from the lower atmosphere and its coupled effects on the ionosphere, and predictions need to be available at higher temporal and spatial resolution. Lower atmospheric influences include atmospheric gravity waves that can couple to traveling ionospheric disturbances that can dramatically alter radio propagation paths. Tropospheric phenomena such as temperature inversions and wind shear also affect VHF and UHF propagation. To be most useful, the ham community needs operational products that provide real time nowcasts and multi-day forecasts which predict how space weather through the whole atmosphere affects radio wave propagation on global scale and at all operational wavelengths.
To help with this effort, hams can provide data with unique spatial and temporal coverage back to the research and forecast community. The amateur radio community has already started this process with the creation of multiple global-scale, real-time propagation reporting systems such as the Weak Signal Propagation Reporting Network (WSPRNet), PSKReporter, and the Reverse Beacon Network (RBN). Studies by the Ham radio Science Citizen Investigation (HamSCI) have shown that data from these systems, if applied correctly, can effectively be used to study ionospheric space weather events. Experienced amateurs keep detailed records of verified point-to-point contacts and have extensive experience operating under a wide variety of geophysical conditions and locations, both of which can provide unique insights when shared with the professional research community. In this presentation, we will describe efforts led by the HamSCI collective to provide this research community feedback through active HamSCI community email lists and annual HamSCI workshops. We will also describe strategies with good initial success at amateur-professional collaboration, including a HamSCI-led amateur radio community - professional research community partnership to create a network of HamSCI Personal Space Weather Stations (PSWS), which will allow citizen scientists to make science-grade space weather observations from their own backyards.

}, url = {https://ams.confex.com/ams/2020Annual/meetingapp.cgi/Paper/370904}, author = {Nathaniel A. Frissell and Philip J. Erickson and Ethan S. Miller and William Liles and H. Ward Silver and R. Carl Luetzelschwab and Tamitha Skov} } @conference {425, title = {Large Scale Traveling Ionospheric Disturbances Observed using HamSCI Amateur Radio, SuperDARN, GNSS TEC, and Ionosondes}, booktitle = {NSF CEDAR (Coupling, Energetics, and Dynamics of Atmospheric Regions)}, year = {2020}, month = {06/2020}, address = {Santa Fe, NM (Virtual)}, url = {http://cedarweb.vsp.ucar.edu/wiki/index.php/2020_Workshop:MainVG}, author = {D. F. Sanchez and N. A. Frissell and G. W. Perry and W. D. Engelke and A. Coster and P. J. Erickson and J. M. Ruohoniemi and J. B. H. Baker and R. C. Luetzelschawb} } @conference {393, title = {Observing Radio Signals of Auroral Origin (Invited Tutorial)}, booktitle = {HamSCI Workshop 2020}, year = {2020}, month = {03/2020}, publisher = {HamSCI}, organization = {HamSCI}, address = {Scranton, PA}, abstract = {

For decades, scientists have deployed instruments similar to amateur radio receiving systems to investigate radio signals of auroral origin observable at ground level in the Arctic and Antarctic. These naturally emitted signals fall into roughly four categories: (1) auroral "roar" occurs in relatively narrow ~100-kHz-wide bands centered around approximately 2.8, 4.2, 5.6, and 6.8 MHz, with center frequency depending on location of observation; (2) auroral "burst" has typical bandwidth 1 MHz occurring between about 1.5 and 4.5 MHz, and usually lasting only a few minutes; (3) auroral "hiss" is a broadband emission extending up to 1 MHz, also of short duration; and (4) "auroral kilometric radiation," also known as AKR, occurs in the frequency range 100-900 kHz and is observed often from spacecraft but much more rarely at ground level and primarily in Antarctica. Most of these signals are optimally received at locations 100-500 km poleward of the aurora. Most of the scientific studies have exploited Arctic and Antarctic research facilities, but there are potential observing locations accessible to intrepid amateurs who have mobile equipment. There are a number of unanswered questions about these signals, including possible existence of other types or sub-types, which could be targets of citizen science.

}, author = {J. LaBelle} } @conference {380, title = {Traveling Ionospheric Disturbances Observed Using Doppler Measurements of Clear-Channel AM Broadcast Transmitters}, booktitle = {HamSCI Workshop 2020}, year = {2020}, month = {03/2020}, publisher = {HamSCI}, organization = {HamSCI}, address = {Scranton, PA}, abstract = {

A system has been developed and is being deployed around the Northeast US using an SDR and Raspberry Pi to receive and measure the Doppler shift of the carrier frequencies of AM broadcast stations to detect Traveling Ionospheric Disturbances.

}, author = {D. McGaw and J. LaBelle} } @conference {299, title = {Conquering The Skip Zone: Short Range Voice and Digital NVIS Communication}, booktitle = {HamSCI Workshop 2019}, year = {2019}, month = {03/2019}, publisher = {HamSCI}, organization = {HamSCI}, address = {Cleveland, OH}, author = {Stephen Hamilton and B. Lebiednik and K. Hager} } @conference {304, title = {Ham Radio for Space Scientists (Invited Tutorial)}, booktitle = {HamSCI Workshop 2019}, year = {2019}, month = {03/2019}, publisher = {HamSCI}, organization = {HamSCI}, address = {Cleveland, OH}, abstract = {

Due to inadvertent interference to commercial and military communications, Amateur Radio operators (hams) were forced to wavelengths of 200 meters and shorter by the Radio Act of 1912. This exile, along with a {\textquotedblleft}we{\textquoteright}ll show them{\textquotedblright} spirit, provided new opportunities for important discoveries and data taking by hams. Initially the sheer number of hams provided wide geographic data coverage. In recent years, data-taking systems have been developed by hams. With the focus of this Workshop being {\textquotedblleft}Ionospheric Effects and Sensing{\textquotedblright}, this presentation will review the contribution by hams to propagation science and their collaboration with the scientific community on propagation issues. Some of the topics covered will be trans-equatorial propagation, long-delayed echoes (LDEs), MINIMUF propagation predictions, fading tests with the Bureau of Standards, the ARRL-IGY propagation research project, the Reverse Beacon Network (RBN), the Weak Signal Propagation Reporter (WSPR) and data from DXpeditions.

}, author = {R. Carl Luetzelschwab} } @article {275, title = {High Frequency Communications Response to Solar Activity in September 2017 as Observed by Amateur Radio Networks}, journal = {Space Weather}, year = {2019}, month = {2019/01/11}, abstract = {

Abstract Numerous solar flares and coronal mass ejection (CME) induced interplanetary shocks associated with solar active region AR12673 caused disturbances to terrestrial high frequency (HF, 3--30 MHz) radio communications from 4-14 September 2017. Simultaneously, Hurricanes Irma and Jose caused significant damage to the Caribbean Islands and parts of Florida. The coincidental timing of both the space weather activity and hurricanes was unfortunate, as HF radio was needed for emergency communications. This paper presents the response of HF amateur radio propagation as observed by the Reverse Beacon Network (RBN) and the Weak Signal Propagation Reporting Network (WSPRNet) to the space weather events of that period. Distributed data coverage from these dense sources provided a unique mix of global and regional coverage of ionospheric response and recovery that revealed several features of storm-time HF propagation dynamics. X-class flares on 6, 7, and 10 September caused acute radio blackouts during the day in the Caribbean with recovery times of tens of minutes to hours, based on the decay time of the flare. A severe geomagnetic storm withKpmax\ =\ 8\ +\ and?SYM\ ?\ Hmin\ =\ \ ?\ 146?nT occurring 7-10 September wiped out ionospheric communications first on 14 MHz and then on 7 MHz starting at~1200 UT 8 September. This storm, combined with affects from additional flare and geomagnetic activity, contributed to a significant suppression of effective HF propagation bands both globally and in the Caribbean for a period of 12 to 15 days.

}, keywords = {Amateur Radio, Geomagnetic Storm, Ham Radio, HF Radio Propagation, Radio Blackout, Solar Flare}, issn = {1542-7390}, doi = {10.1029/2018SW002008}, url = {https://doi.org/10.1029/2018SW002008}, author = {Frissell, Nathaniel A. and Vega, Joshua S. and Markowitz, Evan and Gerrard, Andrew J. and Engelke, William D. and Erickson, Philip J. and Miller, Ethan S. and Luetzelschwab, R. Carl and Bortnik, Jacob} } @conference {295, title = {High Frequency Communications Response to Solar Activity in September 2017 as Observed by Amateur Radio Networks}, booktitle = {HamSCI Workshop 2019}, year = {2019}, month = {03/2019}, publisher = {HamSCI}, organization = {HamSCI}, address = {Cleveland, OH}, abstract = {

Numerous solar flares and coronal mass ejection-induced interplanetary shocks associated with solar active region AR12673 caused disturbances to terrestrial high-frequency (HF, 3{\textendash}30 MHz) radio communications from 4{\textendash}14 September 2017. Simultaneously, Hurricanes Irma and Jose caused significant damage to the Caribbean Islands and parts of Florida. The coincidental timing of both the space weather activity and hurricanes was unfortunate, as HF radio was needed for emergency communications. This paper presents the response of HF amateur radio propagation as observed by the Reverse Beacon Network and the Weak Signal Propagation Reporting Network to the space weather events of that period. Distributed data coverage from these dense sources provided a unique mix of global and regional coverage of ionospheric response and recovery that revealed several features of storm time HF propagation dynamics. X-class flares on 6, 7, and 10 September caused acute radio blackouts during the day in the Caribbean with recovery times of tens of minutes to hours, based on the decay time of the flare. A severe geomagnetic storm with Kpmax = 8+ and SYM-Hmin = -146 nT occurring 7{\textendash}10 September wiped out ionospheric communications first on 14 MHz and then on 7 MHz starting at \~{}1200 UT 8 September. This storm, combined with affects from additional flare and geomagnetic activity, contributed to a significant suppression of effective HF propagation bands both globally and in the Caribbean for a period of 12 to 15 days.

}, author = {Nathaniel A. Frissell and Joshua S. Vega and Evan Markowitz and Andrew J. Gerrard and William D. Engelke and Philip J. Erickson and Ethan S. Miller and R. Carl Luetzelschwab and Jacob Bortnik} } @conference {290, title = {IonTV: Using WWV Timing Reference Signals to Observe Ionospheric Variation}, booktitle = {HamSCI Workshop 2019}, year = {2019}, month = {03/2019}, publisher = {HamSCI}, organization = {HamSCI}, address = {Cleveland, OH}, abstract = {

For decades, an AM modulated time signal has been broadcast at multiple HF frequencies by the National Institute of Standards and Technology (NIST).\  Shortwave radio stations WWV in Colorado and WWVH in Hawaii use these frequencies for the broad dissemination of accurate coordinated universal time information.\  As the HF signal traverses the ionosphere, propagation effects ensue, and the high temporal precision of the original transmitted signal provides an attractive potential for wide-sense monitoring of ionospheric variations.\  We present the results of an ongoing set of data collections and statistical analysis of the received variation in WWV timing signals aimed at extracting ionospheric propagation effects.\  The work includes design of a software defined receiver (SDR) for processing the amplitude modulated dual sideband (AM-DSB) timing signal. By observing the time shift between consecutive seconds of the 10MHz WWV timing signal, reflected from the ionosphere, the change in the effective height of the ionosphere can be estimated.\  Simultaneous measurements taken from different observation angles allow a more accurate sensing of ionospheric electron density variability as projected into refractive effects.\  The project also has a goal of creating a straightforward and reliable way for hobbyists and citizen scientists to demodulate and process their own NIST timing data. We describe a sample analysis of several blocks of WWV received data, both on remote paths and locally through groundwave propagation near the Colorado transmit array, including simultaneous collects. To process the timing data, several approaches will be described, including a heterodyne SDR with a digital phase-locked-loop (PLL).\  Carrier offset tracking using PLL techniques produce Doppler shifts that are associated with traveling ionospheric disturbances and inherent electron density variability.\  Demodulation and amplitude/phase analysis of the 100 Hz subcarrier of WWV can also provide precise delta-time information on ionospheric propagation through examination of variability in arrival of the leading edge of 1 pulse-per-second ticks.\  Results to date suggest that variation between consecutive second markers is a uniformly distributed Gaussian random variable with at least some of this variation due to ionospheric factors, although systematics must be addressed.

}, author = {Philip J. Erickson and William Liles and J. Dusenbury and K.C. Kerby-Patel and Ethan Miller and Gary Bust and Cathryn Mitchell} } @conference {329, title = {IonTV: Using WWV Timing Reference Signals to Observe Ionospheric Variation}, booktitle = {Hamvention HamSCI Forum}, year = {2019}, month = {05/2019}, publisher = {Dayton Amateur Radio Association}, organization = {Dayton Amateur Radio Association}, address = {Xenia, OH}, abstract = {

For decades, an AM modulated time signal has been broadcast at multiple HF frequencies by the National Institute of Standards and Technology (NIST).\  Shortwave radio stations WWV in Colorado and WWVH in Hawaii use these frequencies for the broad dissemination of accurate coordinated universal time information.\  As the HF signal traverses the ionosphere, propagation effects ensue, and the high temporal precision of the original transmitted signal provides an attractive potential for wide-sense monitoring of ionospheric variations.\  We present the results of an ongoing set of data collections and statistical analysis of the received variation in WWV timing signals aimed at extracting ionospheric propagation effects.\  The work includes design of a software defined receiver (SDR) for processing the amplitude modulated dual sideband (AM-DSB) timing signal. By observing the time shift between consecutive seconds of the 10MHz WWV timing signal, reflected from the ionosphere, the change in the effective height of the ionosphere can be estimated.\  Simultaneous measurements taken from different observation angles allow a more accurate sensing of ionospheric electron density variability as projected into refractive effects.\  The project also has a goal of creating a straightforward and reliable way for hobbyists and citizen scientists to demodulate and process their own NIST timing data. We describe a sample analysis of several blocks of WWV received data, both on remote paths and locally through groundwave propagation near the Colorado transmit array, including simultaneous collects. To process the timing data, several approaches will be described, including a heterodyne SDR with a digital phase-locked-loop (PLL).\  Carrier offset tracking using PLL techniques produce Doppler shifts that are associated with traveling ionospheric disturbances and inherent electron density variability.\  Demodulation and amplitude/phase analysis of the 100 Hz subcarrier of WWV can also provide precise delta-time information on ionospheric propagation through examination of variability in arrival of the leading edge of 1 pulse-per-second ticks.\  Results to date suggest that variation between consecutive second markers is a uniformly distributed Gaussian random variable with at least some of this variation due to ionospheric factors, although systematics must be addressed.

}, author = {Philip J. Erickson and William Liles and J. Dusenbury and K.C. Kerby-Patel and Ethan Miller and Gary Bust and Cathryn Mitchell} } @conference {291, title = {Plans for EclipseMob 2024}, booktitle = {HamSCI Workshop 2019}, year = {2019}, month = {03/2019}, publisher = {HamSCI}, organization = {HamSCI}, address = {Cleveland, OH}, abstract = {

During the 2017 solar eclipse, the EclipseMob project conducted a collaborative effort to crowdsource a large-scale geographically distributed measurement of LF radio wave propagation. Do-it-yourself antenna and receiver kits were distributed to libraries, schools, and citizen scientists across the United States, paired with a smartphone app that provided data recording and software-defined radio functionality. While the data collection was ultimately not successful because of a problem with the receiver-smartphone interface, the EclipseMob crowdsourced measurement model still has the potential to make a valuable contribution to the study of the iono- sphere. The availability of low-cost electronic components and modern GPS-based location services presents an opportunity to coordinate nationwide radio measurements that can be performed by hobbyists, students, educators and other citizen scientists. At present, EclipseMob is actively planning for the 2024 eclipse in the eastern United States. The EclipseMob kit will be redesigned for the 2024 eclipse, both to address the previous kit{\textquoteright}s issues and to accommodate recent changes in smartphone technology such as the elimination of the headphone jack on many newer phone models. EclipseMob also envisions a much larger data collection effort in 2024, so outreach, recruitment, and training efforts will need to be conducted on a much larger scale. This talk will discuss how we plan to address some of the logistical and outreach challenges faced by the new, expanded incarnation of EclipseMob.

}, author = {J. Ayala and K. C. Kerby-Patel and William Liles and H. McElderry and J. Nelson and L. Lukes} } @conference {335, title = {Propagation on 630m and 2200m (Booth Talk)}, booktitle = {Dayton Hamvention}, year = {2019}, month = {05/2019}, publisher = {HamSCI}, organization = {HamSCI}, address = {Xenia,OH}, abstract = {

Propagation on 630m and 2200m: Our two new bands provide interesting propagation opportunities. Ionospheric absorption, polarization and refraction will be reviewed on these bands, and compared to 160m and HF (3-30 MHz). General guidelines will be given to enhance your experience on 630m and 2200m.\ \ 

}, author = {Carl Luetzelschwab} } @conference {315, title = {PSWS Science Requirements Panel Discussion (Panel)}, booktitle = {HamSCI Workshop 2019}, year = {2019}, month = {03/2019}, publisher = {HamSCI}, organization = {HamSCI}, address = {Cleveland, OH}, abstract = {

Moderator: Ward Silver, N0AX

  1. Phil Erickson, W1PJE, MIT Haystack Observatory, Radio, Ionospheric, \& Magnetospheric Science
  2. Nathaniel Frissell, W2NAF, NJIT, Radio, Ionospheric, \& Magnetospheric Science
  3. Hyomin Kim, KD2MCR, NJIT, Magnetospheric Physics
  4. Bill Liles, NQ6Z, VLF Science
  5. John Ackermann, N8UR, TAPR, Radio Engineering
  6. Scotty Cowling, WA2DFI, TAPR, Radio Engineering
  7. Tom McDermott, N5EG, TAPR, Radio Engineering
}, author = {John Ackermann and Scotty Cowling and Philip J. Erickson and Nathaniel A. Frissell and Hyomin Kim and William Liles and Thomas McDermott and Ward Silver} } @conference {293, title = {Sudden Ionospheric Disturbances (SIDs) and Personal Space Weather Stations}, booktitle = {HamSCI Workshop 2019}, year = {2019}, month = {03/2019}, publisher = {HamSCI}, organization = {HamSCI}, address = {Cleveland, OH}, abstract = {

This presentation will deal with Sudden Ionospheric Disturbances (SIDs), what they are, what their effects are, how they can be observed easily at home, and observations combined with others to form a more complete view of the ionosphere. SIDs are disturbances on the Sun but can be observed through monitoring VLF transmitters and noticing the change in propagation. Since the transmitters are usually at 30 kHz and less, they are easily observed using just an antenna, amplifier and a computer sound card with appropriate software. There is a worldwide network of collection sites which feeds data to Stanford University. The equipment is easy to build but can also be procured from the Society of Amateur Radio Astronomers (SARA). Different types of equipment will be discussed and shown, including home built and the SARA kit. The antennas used are mainly simple multi-tun loop antennas. Images of different antennas will be shown and it is planned to show an actual antenna. Data collected from SID systems will be displayed and discussed. The presentation will include how people can get involved with SID monitoring and feeding the collective database at Stanford University.

}, author = {Ethan S. Grace and George Lemaster} } @conference {327, title = {Sudden Ionospheric Disturbances (SIDs) and Personal Space Weather Stations}, booktitle = {Hamvention HamSCI Forum}, year = {2019}, month = {05/2019}, publisher = {Dayton Amateur Radio Association}, organization = {Dayton Amateur Radio Association}, address = {Xenia, OH}, abstract = {

This presentation will deal with Sudden Ionospheric Disturbances (SIDs), what they are, what their effects are, how they can be observed easily at home, and observations combined with others to form a more complete view of the ionosphere. SIDs are disturbances on the Sun but can be observed through monitoring VLF transmitters and noticing the change in propagation. Since the transmitters are usually at 30 kHz and less, they are easily observed using just an antenna, amplifier and a computer sound card with appropriate software. There is a worldwide network of collection sites which feeds data to Stanford University. The equipment is easy to build but can also be procured from the Society of Amateur Radio Astronomers (SARA). Different types of equipment will be discussed and shown, including home built and the SARA kit. The antennas used are mainly simple multi-tun loop antennas. Images of different antennas will be shown and it is planned to show an actual antenna. Data collected from SID systems will be displayed and discussed. The presentation will include how people can get involved with SID monitoring and feeding the collective database at Stanford University.

}, author = {Ethan S. Grace and George Lemaster} } @conference {334, title = {The Third Source of F2 Region Variability (Booth Talk)}, booktitle = {Dayton Hamvention}, year = {2019}, month = {05/2019}, publisher = {HamSCI}, organization = {HamSCI}, address = {Xenia, OH}, abstract = {

The Third Source of F2 Region Variability: Although solar radiation instigates the ionization process and causes it to vary in the long-term (e.g., monthly and over a solar cycle) and in the short-term (daily), two other sources of short-term variability contribute significantly to the amount of F2 region ionization at any given location. These are geomagnetic field activity and events in the lower atmosphere coupling up to the ionosphere. This short talk will focus on this third source - events in the lower atmosphere coupling up to the ionosphere.

}, author = {Carl Luetzelschwab} } @conference {311, title = {VLF Sudden Ionospheric Disturbance Receiver (Demonstration)}, booktitle = {HamSCI Workshop 2019}, year = {2019}, month = {03/2019}, publisher = {HamSCI}, organization = {HamSCI}, address = {Cleveland, OH}, author = {Liles, William} } @conference {276, title = {High Frequency Communications Response to Solar Activity in September 2017 as Observed by Amateur Radio Networks}, booktitle = {Fall AGU}, year = {2018}, month = {12/2018}, publisher = {American Geophysical Union}, organization = {American Geophysical Union}, address = {Washington, DC}, abstract = {

Numerous solar flares and coronal mass ejection (CME) induced interplanetary shocks associated with solar active region AR12673 caused disturbances to terrestrial high frequency (HF, 3{\textendash}30 MHz) radio communications from 4-14 September 2017. Simultaneously, Hurricanes Irma and Jose caused significant damage to the Caribbean Islands and parts of Florida. The coincidental timing of both the space weather activity and hurricanes was unfortunate, as HF radio was needed for emergency communications. This paper presents the response of HF amateur radio propagation as observed by the Reverse Beacon Network (RBN) and the Weak Signal Propagation Reporting Network (WSPRNet) to the space weather events of that period. Distributed data coverage from these dense sources provided a unique mix of global and regional coverage of ionospheric response and recovery that revealed several features of storm-time HF propagation dynamics. X-class flares on 6, 7, and 10 September caused acute radio blackouts during the day in the Caribbean with recovery times of tens of minutes to hours, based on the decay time of the flare. A severe geomagnetic storm withKpmax = 8 + and SYM - Hmin = - 146 nT occurring 7-10 September wiped out ionospheric communications first on 14 MHz and then on 7 MHz starting at\ 1200 UT 8 September. This storm, combined with affects from additional flare and geomagnetic activity, contributed to a significant suppression of effective HF propagation bands both globally and in the Caribbean for a period of 12 to 15 days.

}, keywords = {Amateur Radio, Geomagnetic Storm, Ham Radio, HF Radio Propagation, Radio Blackout, Solar Flare}, url = {https://agu.confex.com/agu/fm18/meetingapp.cgi/Paper/419847}, author = {Frissell, Nathaniel A. and Vega, Joshua S. and Markowitz, Evan and Gerrard, Andrew J. and Engelke, William D. and Erickson, Philip J. and Miller, Ethan S. and Luetzelschwab, R. Carl and Bortnik, Jacob} } @article {248, title = {Modeling Amateur Radio Soundings of the Ionospheric Response to the 2017 Great American Eclipse}, journal = {Geophysical Research Letters}, volume = {45}, year = {2018}, month = {05/2018}, type = {Research Letter}, abstract = {

On 21 August 2017, a total solar eclipse traversed the continental United States and caused large-scale changes in ionospheric densities. These were detected as changes in medium and high frequency radio propagation by the Solar Eclipse QSO Party (SEQP) citizen science experiment organized by the Ham Radio Science Citizen Investigation (hamsci.org). This is the first eclipse-ionospheric study to make use of measurements from a citizen-operated, global-scale HF propagation network and develop tools for comparison to a physics-based model ionosphere. Eclipse effects were observed {\textpm}0.3 hr on 1.8 MHz, {\textpm}0.75 hr on 3.5 and 7 MHz, and {\textpm}1 hr on 14 MHz and are consistent with eclipse-induced ionospheric densities. Observations were simulated using the PHaRLAP raytracing toolkit in conjunction with the eclipsed SAMI3 ionospheric model. Model results suggest 1.8, 3.5, and 7 MHz refracted at\ h >= 125 km altitude with elevation angles\ θ >= 22{\textdegree}, while 14 MHz signals refracted at\ h \< 125 km with elevation angles\ θ \< 10{\textdegree}.

}, issn = {1944-8007}, doi = {https://doi.org/10.1029/2018GL077324}, url = {https://doi.org/10.1029/2018GL077324}, author = {N. A. Frissell and J. D. Katz and S. W. Gunning and J. S. Vega and A. J. Gerrard and G. D. Earle and M. L. Moses and M. L. West and J. D. Huba and P. J. Erickson and E. S. Miller and R. B. Gerzoff and W. Liles and H. W. Silver} } @conference {277, title = {Modeling Amateur Radio Soundings of the Ionospheric Response to the 2017 Great American Eclipse}, booktitle = {Fall AGU}, year = {2018}, month = {12/2018}, publisher = {American Geophysical Union Meeting}, organization = {American Geophysical Union Meeting}, address = {Washington, DC}, abstract = {

On 21 August 2017, a total solar eclipse traversed the continental United States and caused large-scale changes in ionospheric densities. These were detected as changes in medium- and high-frequency radio propagation by the Solar Eclipse QSO Party citizen science experiment organized by the Ham Radio Science Citizen Investigation (hamsci.org). This is the first eclipse-ionospheric study to make use of measurements from a citizen-operated, global-scale HF propagation network and develop tools for comparison to a physics-based model ionosphere. Eclipse effects were observed {\textpm}0.3 hr on 1.8 MHz, {\textpm}0.75 hr on 3.5 and 7 MHz, and {\textpm}1 hr on 14 MHz and are consistent with eclipse-induced ionospheric densities. Observations were simulated using the PHaRLAP raytracing toolkit in conjunction with the eclipsed SAMI3 ionospheric model. Model results suggest 1.8, 3.5, and 7 MHz refracted at h>=125 km altitude with elevation angles θ>=22{\textdegree}, while 14 MHz signals refracted at h \< 125 km with elevation angles θ \< 10{\textdegree}.

}, keywords = {Amateur Radio, Citizen Science, Ham Radio, HF propagation, ionosphere, solar eclipse}, url = {https://agu.confex.com/agu/fm18/meetingapp.cgi/Paper/418915}, author = {Frissell, N. A. and Katz, J. D. and Gunning, S. W. and Vega, J. S. and Gerrard, A. J. and Earle, G. D. and Moses, M. L. and West, M. L. and Huba, J. D. and Erickson, P. J. and Miller, E. S. and Gerzoff, R. B. and Liles, W. and Silver, H. W.} } @conference {219, title = {Anthropogenic Space Weather}, booktitle = {HamSCI-UK}, year = {2017}, month = {10/2017}, publisher = {HamSCI-UK}, organization = {HamSCI-UK}, address = {Milton Keynes, UK}, author = {P. J. Erickson and T. I. Gombosi and D. N. Baker and A. Balogh and J. D. Huba and L. J. Lanzerotti and J. C. Foster and J. M. Albert and J. F. Fennell and E. V. Mishin and M. J. Starks and A. N. Jaynes and X. Li and S. G. Kanekal and C. Kletzing} } @conference {223, title = {Collaborative Use of Solar Eclipses to Study the Ionosphere}, booktitle = {HamSCI-UK}, year = {2017}, month = {10/2017}, publisher = {HamSCI-UK}, organization = {HamSCI-UK}, address = {Milton Keynes, UK}, author = {W. C. Liles and C. N. Mitchell and K. C. Kerby-Patel and J. Nelson and L. Lukes} } @conference {161, title = {Introduction to Space Weather and Propagation}, booktitle = {Dayton Hamvention}, year = {2017}, address = {Xenia, OH}, abstract = {

A broad overview of space weather and the effects on propagation is presented, including a review of general band characteristics, and a discussion of expectations for the bands during the 2017 Total Solar Eclipse.

}, author = {Carl Luetzelschwab} } @conference {215, title = {Outstanding Problems in Radio Propagation}, booktitle = {HamSCI-UK}, year = {2017}, month = {10/2017}, publisher = {HamSCI-UK}, organization = {HamSCI-UK}, address = {Milton Keynes, UK}, author = {C. Luetzelschwab} } @conference {158, title = {On the use of solar eclipses to study the ionosphere}, booktitle = {15th International Ionospheric Effects Symposium IES2017}, year = {2017}, month = {05/2017}, address = {Alexandria, VA}, abstract = {

Exploring the effects of solar eclipses on radio wave propagation has been an active area of research since the first experiments conducted in 1912. In the first few decades of ionospheric physics, researchers started to explore the natural laboratory of the upper atmosphere. Solar eclipses offered a rare opportunity to undertake an active experiment. The results stimulated much scientific discussion.
Early users of radio noticed that propagation was different during night and day. A solar eclipse provided the opportunity to study this day/night effect with much sharper boundaries than at sunrise and sunset, when gradual changes occur along with temperature changes in the atmosphere and variations in the sun angle.
Plots of amplitude time series were hypothesized to indicate the recombination rates and re- ionization rates of the ionosphere during and after the eclipse, though not all time-amplitude plots showed the same curve shapes. A few studies used multiple receivers paired with one transmitter for one eclipse, with a 5:1 ratio as the upper bound. In these cases, the signal amplitude plots generated for data received from the five receive sites for one transmitter varied greatly in shape.

}, author = {W. Liles and C. Mitchell and M. Cohen and G. Earle and N. Frissell and K. Kirby-Patel and L. Lukes and E. Miller and M. Moses and J. Nelson and J. Rockway} } @conference {164, title = {VLF/LF and the 2017 Total Solar Eclipse}, booktitle = {Dayton Hamvention}, year = {2017}, address = {Xenia, OH}, abstract = {

Previous solar eclipse studies have observed different propagation effects at VLF/LF frequencies (3-300 kHz) compared with those observed at HF (3-30 MHz) frequencies. These differences are primarily due to the much longer wavelengths at lower frequencies in concert with ionospheric D layer interactions. To better understand the unusual eclipse-induced effects at VLF/LF frequencies, we present EclipseMob, a crowdsourced collection effort that will use smart phones as simple VLF/LF software defined radio (SDR) receivers to record changes in propagation from known transmitters during the 2017 Total Solar Eclipse.

}, author = {William Liles and L. Lukes and J. Nelson and K. Kerby-Patel} } @article {139, title = {The New Sunspot Numbers}, volume = {100}, year = {2016}, month = {10/2016}, pages = {38-41}, issn = {0033-4812}, url = {http://www.nxtbook.com/nxtbooks/arrl/qst_201610/index.php}, author = {Carl Luetzelschwab} }