@article {1007, title = {Detecting changes in along-path HF propagation during the April 2024 total solar eclipse with radio amateurs and low-cost instrumentation}, journal = {Frontiers in Astronomy and Space Sciences}, year = {2026}, month = {Feb/2026}, abstract = {

The total solar eclipse of April 8, 2024 presented a uniquely favorable circumstance for radio science. The Moon{\textquoteright}s shadow passed near Canadian time standard station CHU, which transmits in the high frequency (HF,\ i.e., 3{\textendash}30 MHz) band. It was therefore possible to observe signal changes due to shifting ionospheric conditions along the path of the eclipse by using CHU as a signal of opportunity. In under 3 months, our undergraduate team developed and deployed low-cost instrumentation to record CHU for timing and amplitude analysis. 18 units were distributed across 6 locations roughly aligned with the eclipse path. Each unit contained a radio recorder which retained time traceability to UTC via GPS time synchronization, allowing capture of the CHU signal with no unbounded error beyond the 50 {\textmu}s sampling interval. Seven units captured changes in the received signal during the eclipse, most notably a tenfold increase in the signal strength at 7.85 MHz for a unit in Little Rock, AR. Its timing suggests a one-hop propagation path reflecting in the ionosphere over Cleveland, OH. The stations were deployed to and maintained by volunteers contacted through the amateur radio and citizen science community. This campaign demonstrates the accessibility and effectiveness of research using low-cost instrumentation and the power of citizen science.

}, doi = {10.3389/fspas.2025.1720301}, url = {https://www.frontiersin.org/journals/astronomy-and-space-sciences/articles/10.3389/fspas.2025.1720301/full}, author = {Maris Usis and Adam Goodman and Laura Schwartz and David Kazdan and Kristina Collins and John Gibbons and Shashank Sastry and Lucy Ayres and Christopher Brault and Seth Byas and Michael Dimple and Michelle Dowell and Rowan Eggert and Aras Erdag and James Ervin and Dave Goodwin and Scarlett Nelson and Stephen Nichols and Olivia Tulgetske and Christian Zorman} } @proceedings {1031, title = {Telling Radio Stories Through Stamps: Amateur Ham Radio and Project Magnet in Philately}, year = {2026}, month = {03/2026}, publisher = {HamSCI}, address = {Newington, CT}, abstract = {

This poster explores how amateur ham radio and Project Magnet (U.S. Navy) can be understood through postage stamps and special covers. Stamps provide visual and historical evidence of the growth of radio\ communication and large-scale scientific efforts to measure Earth{\textquoteright}s magnetic field. Amateur radio images show antennas and global contact\ symbols, reflecting the rise of a worldwide communication network built by individuals. Project Magnet, conducted around 1951, carried out airborne and shipborne geomagnetic surveys to improve magnetic charts for navigation and research. By examining philatelic materials related to radio, navigation, survey aircraft, and magnetic mapping, this poster shows how both amateur operators and naval scientists contributed to understanding invisible natural forces.

}, author = {Briti Deb} } @proceedings {931, title = {Analysis by Citizen Scientists of Doppler Radio Observations of the April, 2024 Solar Eclipse}, year = {2025}, month = {03/2025}, publisher = {HamSCI}, address = {Newark, NJ}, abstract = {

The HamSCI community (Ham Radio Science Citizen Investigation) has analyzed high frequency radio observations of the total solar eclipse of April 8, 2024 and found interesting correlations. Nearly fifty ham radio operators recorded over 200 Doppler time series of the national time standard transmitters WWV in Colorado and CHU in Canada using specialized GRAPE (Great Radio Amateur Propagation Experiment) receivers. These observations are archived at the Personal Space Weather Station website, and cover ten frequencies from 0.6 to 25 MHz. There were over sixty different paths from transmitter to receiver at various angles across and along the path of totality from Texas to Maine. For each observation six citizen scientists collected demographic data, found distances and midpoints (where radio signals are reflected from the ionosphere), noted local eclipse information, measured the maximum Doppler shifts, counted multi-path signals, and judged the symmetry of the S-shaped Doppler curves over ingress and egress time periods. We found that the Doppler shifts depend mostly on the Sun{\textquoteright}s obscuration at the midpoint, but also on the carrier frequency and the distance between the transmitter and the receiver. At closer distances a radio wave measured a greater change in the path length as the bottom of the ionosphere retreated skyward and then returned as the Moon uncovered the Sun. \ 

}, author = {Mary Lou West and Nathaniel Frissell and Gary Mikitin and Gregory Popelas and Ronald Wilcox and McKenzie Denton and Robert Spalletta and William Engelke and Gwyn Griffiths and Steve Cerwin} } @proceedings {934, title = {The HamSCI Book Club}, year = {2025}, month = {03/2025}, publisher = {HamSCI}, address = {Newark, NJ}, abstract = {

\ We will discuss several radio-related works of English literature: \ Romeo \& Juliet\ romeo-and-juliet_PDF_FolgerShakespeare.pdf\ and Code Poems\ Weiner_Hannah_Code_Poems.pdf

}, author = {David Kazdan and Kristina Collins and Leah Davydov} } @proceedings {978, title = {HamSCI{\textquoteright}s Meteor Scatter QSO Party 2025}, year = {2025}, month = {03/2025}, publisher = {HamSCI}, address = {Newark, NJ}, abstract = {

The Meteor Scatter QSO Party 2025 is an on-the-air experiment designed to study meteor scatter propagation on HF bands below 30 MHz using the MSK144 mode in the digital communication software WSJT-X. The primary goal is to generate dense, geographically diverse datasets to analyze the feasibility of HF meteor scatter for future scientific research. The experiment will be conducted during the Perseids meteor shower in August 2025, with a secondary event planned for the Geminids meteor shower in December 2025.

}, author = {McKenzie Denton} } @proceedings {929, title = {HamSCI Solar Eclipse QSO Party (SEQP): Observations and Modeling on Ionospheric Effects}, year = {2025}, month = {03/2025}, publisher = {HamSCI}, address = {Newark, NJ}, abstract = {

This study investigates the ionospheric changes during the solar eclipse of April 2024 using data from the HamSCI Solar Eclipse QSO Party (SEQP). SEQP collected radio communication data reported by ham radio operators and global automated receiving networks (e.g., WSPRNet, the Reverse Beacon Network, and PSKReporter). The datasets include radio communications at multiple frequencies in the high frequency (HF) and very high frequency (VHF) bands. Thousands of ham radio operators across the contiguous United States (CONUS) and around the globe contributed to the observations with unprecedented temporal, spatial, and spectral coverage. SEQP datasets are used to infer ionospheric state before, during, and after the solar eclipse. We use the ham radio datasets along with PHaRLAP raytrace modeling to infer the ionospheric response of the solar eclipse and also evaluate the outputs of the physics-based model SAMI3 for the eclipse ionosphere. Our findings suggest that the solar eclipse increased the range of radio communications at lower HF band (3.5, 7, 10 MHz), but decreased the longer range communications at higher HF band (21, 24, 28 MHz). Ham radio datasets from stations continually operated during the eclipse show an earlier opening of radio links between the US and Europe on the eclipse day. We are conducting modeling studies to understand the causes of changes in ham radio observations and to examine the potential combined effect of the sunset terminator and eclipse shadow during the later phase of the eclipse.

}, author = {Kuldeep Pandey and Gareth Perry and Nathaniel Frissell and Travis Atkinson and William Engelke and Joseph Huba and Mary Lou West and Philip Gladstone and Cameron Cushing and McKenzie Denton and Edward Efchak and Gary Mikitin and H. Ward Silver} } @proceedings {954, title = {Investigation of Electromagnetic Wave Propagation in CB Radio with Elementary Students: A {\textquoteright}Super Bowl{\textquoteright} Mystery}, year = {2025}, month = {03/2025}, publisher = {HamSCI}, address = {Newark, NJ}, abstract = {

The Citizen{\textquoteright}s Band Radio Service (CB Radio), as defined by the United States Code of Federal Regulations, is a two-way voice communication service operating in the 27 MHz band, divided into 40 channels with a power limit of 4 Watts. Classified as High Frequency (HF), CB radio shares the spectrum with other services, and in Brazil, it offers similar functionalities with simplified registration. Motivated by the accessibility and low cost of equipment, elementary school students in Santa Catarina (-26.8668712, -49.2317786) conducted an experiment during lessons on electromagnetic waves. Using Aquarius RP40 and PRO401HH CB radios, the students received signals on channel 06 (27.025 MHz) in Amplitude Modulation (AM), identified as originating from the USA and related to the {\textquotedblleft}Super Bowl{\textquotedblright} broadcast, through the analysis of the message content. After researching the possible source of the transmission, it was found that the signal travels approximately 7,850 km from its origin to the receiver, a distance estimated using geolocation tools and information from possible broadcasters found online, demonstrating the propagation of HF waves through the ionosphere. This region of the upper atmosphere reflects radio waves back to Earth, enabling long-distance communication through multiple {\textquotedblleft}skips{\textquotedblright} between the ionospheric layers and the Earth{\textquoteright}s surface. The observed variation in the received signal intensity, consistent with fluctuations in ionospheric electron density, highlights the influence of the ionosphere on signal propagation. Although long-distance reception may raise questions about transmission power, antennas, and other factors, this study emphasizes the role of the ionosphere, providing students with hands-on experience with radio communication equipment, deepening their understanding of electromagnetic waves through the ionospheric layer, and inspiring scientific inquiry.

}, author = {Alexandre Takio Kitagawa and Anni Carolini Maffezzolli and Ana Carolina Hemmer de Oliveira and Emanuella Brandl} } @proceedings {943, title = {The Physical Nature of Sporadic-E}, year = {2025}, month = {03/2025}, publisher = {HamSCI}, address = {Newark, NJ}, abstract = {

Sporadic-E is different from other forms of ionospheric propagation, regularly supporting long distance contacts well into the VHF range. It{\textquoteright}s also well-known to be really hard to predict, with signals that are highly unstable and localised. But why? What is it about the physical properties of sporadic-E layers that drive that propagation behaviour? This presentation will explain what is currently known about the physical nature of sporadic-E, introducing a range of techniques for investigating the ionosphere along the way.

}, author = {Chris Deacon} } @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 {832, title = {"And Science will Know To-morrow": An Exploration of Rudyard Kipling{\textquoteright}s "Wireless"}, year = {2024}, month = {03/2024}, publisher = {HamSCI}, address = {Cleveland, OH}, abstract = {

Written in 1902, Rudyard Kipling{\textquoteright}s short story "Wireless" juxtaposes early exercises in short-wave radio transmission with Victorian spiritualism. It tells a dual account of a misdirected "transmissions" as one man{\textquoteright}s interception of wireless telegraph signals plays out alongside seeming instant of spiritual possession. While the supernatural element of the story remains ambiguous--and receives a curt dismissal from the narrative{\textquoteright}s suspected medium himself--the "Marconi experiment" playing out in the background has long proven an intriguing element of the narrative. For those familiar with much earlier proposed theories of animal magnetism upon which seances often rested, wireless technology could readily be read as keeping in step with popular theories of the era eventually discarded as pseudoscience. In this talk, I will look to the how Kipling presents a story in which radio is superimposed upon the pre-existing "scientific" paradigms of mesmeric models of psychical phenomena--exploring how Marconi{\textquoteright}s cutting edge experiments might be read by an audience primed to believe in very different sorts of waves and forces.

}, author = {Leah Davydov} } @proceedings {860, title = {Construction of a Table-Top Antenna Range for Learning Electromagnetics Concepts}, year = {2024}, month = {03/2024}, publisher = {HamSCI}, address = {Cleveland, OH}, abstract = {

Antenna construction and measurement provide an effective method of teaching electromagnetic and antenna concepts, including polarization, gain, directivity, and reflection. During the Spring 2024 semester, the University of Scranton EE 448 Electromagnetics II class is undertaking a project to build a table-top antenna range at 2450 MHz (λ = 12 cm). The table top range will give hands-on visual and intuitive reinforcement of abstract concepts covered mathematically in the course textbook. This frequency was chosen due to the convenient size of antennas and the fact that the antennas will be usable in the 2.4 GHz Industrial, Scientific, and Medical (ISM) and amateur bands. ISM band applications include WiFi, Bluetooth, RFID, NFC, and more. In this presentation and poster, we demonstrate three types of antennas the class has built so far: dipoles, dipoles with corner reflectors, and loops over ground planes. We also demonstrate the use of a NanoVNA to measure antenna properties, as well as show ideas for future projects.

}, author = {Augustine Brapoh and Matthew Dittmar and Aidan Szabo and Robert Troy and Nathaniel Frissell and Stephen A. Cerwin} } @proceedings {867, title = {PyLAP/PHaRLAP HF Ray Tracing and SAMI3: Integration and Refactoring}, year = {2024}, month = {03/2024}, publisher = {HamSCI}, address = {Cleveland, OH}, abstract = {

PyLAP is a high frequency (HF) ray tracing toolkit that is used to model radio wave propagation through the ionosphere. Currently PyLAP uses the empirical International Reference Ionosphere (IRI) model. In an effort to use PyLAP to observe more discrete structures in ionosphere that are otherwise unobservable with IRI, PyLAP is being Integrated with the Physics-based SAMI3 Model of the ionosphere. Along with this there will be an effort to refactor some of the current PyLAP codebase so that it is more readable and usable for anyone using the current system including both professional and citizen scientists.

}, author = {Devin Diehl and Rachel Boedicker and Joseph Huba and Nathaniel A. Frissell} } @proceedings {868, title = {Ray-trace modelling of diurnal variation in two-hop sidescatter propagation}, year = {2024}, month = {03/2024}, publisher = {HamSCI}, address = {Cleveland, OH}, abstract = {

Two-hop sidescatter, an off-great circle propagation mode enabling above-the-basic-MUF communications, is identified by low SNR and high spectral spread (width between -3 dB points). Observable at 7 MHz and above, as a daytime mode it enables propagation from 10s km to 100s km. Additionally, it may appear before, and or after, great-circle one-hop propagation as it operates with a lower F2 layer critical frequency. We have devised a computationally efficient modelling approach for two-hop sidescatter using 3D ray tracing. First, ray landing spots from a transmitter are found over 360{\textdegree}\ azimuth and a sensible range of elevations. Second, the process is repeated for a transmitter at the receiver. The key assumption is that reciprocity holds sufficiently to avoid the computationally demanding need to place a transmitter at every transmitter ray landing spot. A scattering metric, the product of the number of landing spots from transmitter and pseudo-transmitter in a 1{\textdegree}x1{\textdegree}\ area, is a useful approximation to the location and strength of the sidescatter. The off-great circle scattering location from the model has been verified by a rotating-antenna experiment at 14 MHz on paths from Northern California to Utah and Oregon using FST4W digital mode. The diurnal variations of sidescatter location and strength are particularly interesting for a meridional transmitter and receiver geometry: morning (local time) scatter from the east, from land on the California to Oregon path, with afternoon through nighttime scatter from the west, from the ocean. We discuss a qualitative comparison of hourly model simulations with signal level and circuit reliability data from FST4W spots. The nighttime minimum in both parameters is pronounced in the observations and model. An afternoon dip in circuit reliability, without reduction in signal level, is tentatively explained by the model showing strongest scatter alternating between east and west before settling to the west. We postulate that severe multipath scatter from both east and west, land and ocean, sufficiently increased frequency spread to reduce probability of decode for the ~6 Hz bandwidth FST4W mode. This study illustrates the usefulness of combining 3D ray tracing with purposeful observations to explain an underappreciated propagation mode.

}, author = {Gwyn Griffiths and Devin Diehl and R. Lynn Rhymes and Frederick Wahl} } @proceedings {852, title = {Why is sporadic-E propagation so weird?}, year = {2024}, month = {03/2024}, publisher = {HamSCI}, address = {Cleveland, OH}, abstract = {

Mid-latitude sporadic-E ("Es") clouds are transient, thin layers of dense but patchy ionization which appear in the E region of the ionosphere. The process of formation of Es is different from that of the background ionosphere and can, by comparison, produce much higher ionization densities. Sporadic-E propagation is well known to radio amateurs because it allows communication at higher frequencies and/or over shorter skip distances than is possible via the background ionosphere, but Es is also currently the subject of much academic research. This is partly because of the disruptive impact of Es on satellite communications and satellite radars, but there is also growing scientific interest in the Mesosphere /\ Lower Thermosphere region of the upper atmosphere, which is where Es mainly occurs. The thin, intense, and variable nature of Es means that reflected signals can have quite extreme temporal, spatial, and polarization characteristics. My PhD research showed that the reflection process at 50 MHz is primarily magnetoionic in nature, but many detailed features remain to be explained. To explore the observed polarization behaviour in more detail and to link that behaviour to the physical properties of the Es layers, a PHaRLAP-based raytrace simulation has been developed which predicts polarization parameters a signal passes through an Es cloud. As a case study, the observed significant and systematic differences in the polarization of the signals received in the UK over very similar paths from beacons in Hungary and Slovenia have been investigated in detail. Each of the two beacons shows strongly defined elliptical polarization, but the sense of rotation and predominant tilt angle are consistently opposite from each other, over multiple Es reflection events and on multiple days. This presentation will summarize the earlier work and then describe the building and testing of the PHaRLAP simulation model and the case study results obtained so far. Finally, outstanding questions about the weird nature of Es propagation will be discussed and opportunities for further work described.

}, author = {Chris Deacon} } @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 {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 {724, title = {Field-Aligned Potential Drops in an Ionospheric Streamer}, year = {2023}, month = {03/2023}, publisher = {HamSCI}, address = {Scranton, PA}, abstract = {

Field-aligned potential drops occur primarily in regions of strong upward field-aligned currents, where they can decouple the ionospheric and magnetospheric dynamics. They have been a challenge to incorporate into global magnetosphere modeling efforts. Low-entropy bubbles can form ionospheric streamers in the context of field-aligned potential drops. We have made a simple zeroth-order analytic model with order-of-magnitude reasonable field values. The model{\textquoteright}s parameter space comprises resistivity, bubble asymmetry, conductivity enhancement, and an additional parameter which can be used to adjust the entropy profiles across the bubble. We are currently exploring this parameter space and examining the resulting differences between the resulting ionospheric and magnetospheric electric fields (including electric field-reversals).\  An examination of whether bursty bulk flows or flow bursts are more likely to be responsible for streamers is ongoing.\  Both previous runs of the Rice Convection Model and data are being used to fit parameters and examine reasonable parameter regimes.

}, author = {Jason Derr and Sina Sadegzadeh and Richard Wolf and Frank Toffoletto and Jian Yang and Weiqin Sun} } @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} } @proceedings {764, title = {Medium Scale Traveling Ionospheric Disturbances and their Connection to the Lower and Middle Atmosphere}, year = {2023}, month = {03/2023}, publisher = {HamSCI}, address = {Scranton, PA}, author = {Nathaniel A. Frissell and Francis Tholley and V. Lynn Harvey and Sophie R. Phillips and Katrina Bossert and Sevag Derghazarian and Larisa Goncharenko and Richard Collins and Mary Lou West and Diego F. Sanchez and Gareth W. Perry and Robert B. Gerzoff and Philip J. Erickson and William D. Engelke and Nicholas Callahan and Lucas Underbakke and Travis Atkison and J. Michael Ruohoniemi and Joseph B. H. Baker} } @proceedings {756, title = {A New Station for the W3USR University of Scranton Amateur Radio Club}, year = {2023}, month = {03/2023}, publisher = {HamSCI}, address = {Scranton, PA}, author = {Tom Pisano and Nathaniel Frissell and Jeff DePolo and The W3USR University of Scranton Amateur Radio Club} } @proceedings {745, title = {Power Factor Detection and Correction of a Variable Speed AC motor}, year = {2023}, month = {03/2023}, publisher = {HamSCI}, address = {Scranton, PA}, author = {Christian Chakirus and Robert Brudnicki and Robert Troy and Kenneth Dudeck} } @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} } @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 {603, title = {Consolidated Amateur Radio Reports as Indicators of Intense Sporadic-E Layers}, year = {2022}, month = {03/2022}, publisher = {HamSCI}, address = {Huntsville, AL}, abstract = {

A case study is presented to demonstrate the usefulness and validity of consolidated amateur ({\textquoteleft}ham{\textquoteright}) radio signal reports as indicators of the presence of ionospheric sporadic-E (Es). It is shown that amateur data can provide an important supplement to other techniques, allowing the detection of Es where no suitable ionosonde or satellite radio occultation measurements are available. The effectiveness of the approach is demonstrated by reference to ionosonde data, and the advantages and limitations of the technique are discussed.

}, author = {Chris Deacon and Cathryn Mitchell and Robert Watson} } @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 {621, title = {Ionosphere Plasma Density Estimation by Ray Tracing Optimization}, year = {2022}, month = {03/2022}, publisher = {HamSCI}, address = {Huntsville, AL}, abstract = {

In recent years, several studies have tried to estimate volumetric electron density by methods of refraction tomography on an HF network. These methods involve a dynamic optimization problem where the ray tracing equations have to be solved in every optimization step. Furthermore, to improve the estimates, data from incoherent scatter radars and GPS can also be assimilated. However, the computational complexity involved in these estimates is considerable. Even though some efforts have been implemented to reduce this complexity, it is clear that new methods have to be explored. Furthermore, to our knowledge, the possibility of using the frequency sweep capability of ionosondes has not been considered. This work simplifies the dispersion relation to an unmagnetized collisionless plasma to focus our efforts on the inverse process. Instead of using sensitivity analysis, we propose a direct collocation approach, where the points on the transmitter and receiver can be fixed, therefore, eliminating the chances of the extreme misfire.

}, author = {David de la Torre and Enrique Rojas} } @conference {609, title = {The Radio JOVE Project 2.0}, booktitle = {HamSCI Workshop 2022}, year = {2022}, month = {03/2022}, publisher = {HamSCI}, organization = {HamSCI}, address = {Huntsville, AL}, abstract = {

Radio JOVE is a well-known public outreach, education, and citizen science project using radio astronomy and a hands-on radio telescope for science inquiry and education. Radio JOVE 2.0 is a new direction using radio spectrographs to provide a path for radio enthusiasts to grow into citizen scientists capable of operating their own radio observatory and providing science-quality data to an archive. Citizen scientists will have opportunities for presenting and publishing scientific papers. Radio JOVE 2.0 uses more capable software defined radios (SDRs) and spectrograph recording software as a low-cost ($300) radio spectrograph that can address more science questions related to heliophysics, planetary and space weather science, and radio wave propagation. Our goals are: (1) Increase participant access and expand an existing radio spectrograph network, (2) Test and develop radio spectrograph hardware and software, (3) Upgrade the science capability of the data archive, and (4) Develop training modules to help a hobbyist become a citizen scientist. We will overview Radio JOVE 2.0 and give a short demonstration of the new radio spectrograph using the SDRplay RSP1A receiver with a dipole antenna and the associated Radio-Sky Spectrograph (RSS) software.

}, author = {C. Higgins and S. Fung and L. Garcia and J. Thieman and J. Sky and D. Typinski and R. Flagg and J. Brown and F. Reyes and J. Gass and L. Dodd and T. Ashcraft and W. Greenman and S. Blair} } @proceedings {499, title = {Implementation of a point-to-point ray tracer}, year = {2021}, month = {03/2021}, publisher = {HamSCI}, address = {Scranton, PA (Virtual)}, abstract = {

Most ray tracers treat the problem as a Hamiltonian optics problem given an index of refraction, i.e., the ionosphere in this case.\  However, Coleman 2011 developed a method for ray tracing that used a direct variation method.\  The advantage of this method is that the endpoints of the ray remained fixed, while in more standard ray tracer, rays are launched until a link is made between the transmitter and receiver.\  Development of this method may provide a potentially efficient method for determining the link between a transmitter receiver pair, given a model ionosphere.\  We present efforts toward implementing the methodology described by Coleman 2011.

}, url = {https://hamsci2021-uscranton.ipostersessions.com/?s=3A-71-3B-21-F1-51-7F-5B-44-BE-57-61-1A-79-02-6B}, author = {Scott Driggers and Steven R. Kaeppler} } @proceedings {483, title = {InFlaMo {\textendash} an European SID Monitoring Network Celebrates its First Solar Cycle}, year = {2021}, month = {03/2021}, publisher = {HamSCI}, address = {Scranton, PA (Virtual)}, abstract = {

The influence of solar X-ray radiation on terrestrial radio communication was found in the early 20ies century. But it was not understood immediately. Radio communication was a challenging topic back then, and became quickly a topic taught in science classes at school. Half a century later {\textendash} with the start of the space age - it became evident, that the study of Earth{\textquoteright}s upper atmosphere was solving this question. Solar and other cosmic radiation is responsible for the condition of the ionosphere and the cause of black-outs in long range radio communication. Today, most of the ionospheric very long frequency (VLF) radio propagation phenomena are known and presumably almost completely understood, though it stays a challenging topic listening to the ionospheric disturbances caused by our Sun. The recent development of low-cost software defined radio wave receivers (SDRs) are an ongoing process and opens many new opportunities for applications in people{\textquoteright}s daily lives and in education. Furthermore, monitoring of Earth{\textquoteright}s lower ionosphere by utilizing VLF monitors, which are based on SDR technology, it offers new indirect insights into what happens on the Sun. Therefore, one aim of this presentation is to reach out to an educator community as well as citizen scientists to make the InFlaMo (Indirect solar Flare Monitoring) project (http://www.inflamo.org) better known. For almost the entire solar cycle 24 VLF data (20 to 30 kHz) was collected and preprocessed. The scientific analysis of the VLF data is an ongoing activity. For scientific and educational use InFlaMo project data is shared with researchers, educators and citizen scientists. The other aim is to enlarge the network of ground based multichannel SDR-receivers from Europe to overseas. The European network stations have been or are presently in Germany, Finland, Russian Federation and Czech Republic. With this rather inexpensive method monitoring the state of the ionosphere and recording the appearance of solar X-ray flares can be made available for class-room usage.

}, url = {https://hamsci2021-uscranton.ipostersessions.com/?s=B3-60-56-B3-59-06-92-97-C6-9C-F3-8A-9B-41-D1-59}, author = {Michael Danielides and V. Skripatchev and J. Chum} } @conference {472, title = {INVITED AMATEUR RADIO TUTORIAL: Amateur Radio Observations and The Science of Midlatitude Sporadic E}, booktitle = {HamSCI Workshop 2021}, year = {2021}, month = {03/2021}, publisher = {HamSCI}, organization = {HamSCI}, address = {Scranton, PA (Virtual)}, abstract = {
Abstract:\ Amateurs may ask, {\textquotedblleft}Why do we see Sporadic E like propagation in November and December, when many of the variables like UV radiation and solar exposure are at a minimum, unlike the very active sporadic-E summer months?{\textquotedblright} How are sporadic-E transatlantic VHF communications possible between North America and Europe? In his tutorial, Joe K1YOW will explain what Sporadic E is, how amateur operators use Sporadic E to enable long-distance VHF communications, current theories of Sporadic E formation, and how we might be able to better understand Es formation by examining amateur radio propagation logs. Joe{\textquoteright}s studies of Sporadic E using amateur radio have been published both in\ QST (2017)\ and\ CQ Magazine (2020).
Bio:\ Joe Dzekevich, K1YOW, was first licensed in 1962 and currently holds an Amateur Extra Class license. He graduated from Northeastern University in 1977 with a B.S. in Industrial Technology and holds a M.B.A. from Clark University (1985). Joe is currently a retired Reliability Engineering Fellow who has worked for Bell Telephone Labs, Digital Equipment Corporation, Chipcom/3Com and Raytheon. Joe is also a senior member of the IEEE Reliability Society, where he held various offices in the local IEEE Boston Reliability Chapter and developed and taught many of the chapter{\textquoteright}s courses. He is a member of NVARC (Nashoba Valley Amateur Radio Club), the ARRL, and HamSCI. He has always been interested in radio propagation, starting back in 1965 where he subscribed to the CRPL (Central Radio Prediction Lab) Ionospheric Predictions, where one used monthly CRPL prediction maps to chart predicted E-Layer and F-Layer radio paths.
}, author = {Joseph Dzekevich} } @proceedings {485, title = {RJOVER: An alternative approach using SDR technology to reduce costs for the NASA Radio JOVE citizen science effort}, year = {2021}, month = {03/2021}, publisher = {HamSCI}, address = {Scranton, PA (Virtual)}, abstract = {

The NASA-run citizen science project, Radio JOVE, utilizes widespread distribution of single and dual-dipole antenna receiving stations to study the magnetic interactions between Jupiter and its moon, Io. The citizen science effort has been well established and maintained since 1998, and the Radio JOVE project team has streamlined kit distribution and assembly documentation for amateur data collectors and hobbyists. The antennas, receiver, software, and related components are available for purchase in kits that range in price from depending on the level of {\textquotedblleft}pre-assembly{\textquotedblright}. For instance, we estimate that the prices of un-assembled and fully assembled kit receivers are approximately $95 and $225, respectively. Establishing a Radio JOVE receiving station is no small task, and these prices are reasonable and appropriate. To further data collection accessibility and broaden the participating audience, however, we seek to further reduce these costs-- specifically that of the receiver. Our primary goal is to code, integrate, and test a software-defined radio (SDR) receiver for Radio JOVE data collection to verify whether the technology could be a less expensive alternative to the original distributed kit receiver. By coordinating with the Case Western Reserve University (CWRU) Research Farm, as well as with guidance from faculty in the CWRU Electrical, Computer, and Science Engineering (ECSE) department and the Radio JOVE Project Team, we hope to establish a Radio JOVE receiving station at CWRU whereupon we can test our alternative SDR receiver for Jovian signal collection. If our alternative receiver works on a level comparable to the existing kit receiver, we can offer a cheaper, more modern and digital age approach that could appeal to a wider audience including those working with a tighter budget and those who are interested in software-defined radio, all of whom simply want to help the scientific effort.\ 

}, url = {https://hamsci2021-uscranton.ipostersessions.com/?s=8D-A5-71-AF-BD-32-32-6C-C3-71-E2-59-AB-87-B0-0D}, author = {Tyler Kovach and Skylar Dannhoff and Jared May} } @proceedings {476, title = {Simulation and Comparison of Weak-Signal VHF Propagation}, year = {2021}, month = {03/2021}, publisher = {HamSCI}, address = {Scranton, PA (Virtual)}, abstract = {

Space weather{\textquoteright}s intense variance has a seemingly random effect on radio propagation in the Very High Frequency (VHF) range. Key models are built to analyze and estimate performance of wireless systems in these weak-signal propagation mediums. Chiefly, meteor burst communication, auroral propagation, and earth-moon-earth communication models are built and simulated on MATLAB. The results are confirmed through experimental testing and data comparison. Overall, modeling of these space weather events proves immense usefulness in predicting effectiveness of radio equipment through these weak-signal modes.

}, url = {https://hamsci2021-uscranton.ipostersessions.com/?s=0B-3C-92-BC-7A-A2-35-0C-0B-52-1C-29-5A-03-4F-46}, author = {Nolan Pearce and Kate Duncan} } @proceedings {468, title = {"Sprinkles" or "Mirrors"? Exploring the true nature of VHF propagation via sporadic-E}, year = {2021}, month = {03/2021}, publisher = {HamSCI}, address = {Scranton, PA (Virtual)}, abstract = {

Mid-latitude sporadic-E clouds (commonly abbreviated as {\textquoteleft}Es{\textquoteright}) are a transient feature consisting of thin layers of dense, but patchy, ionization which occur in the E region of the ionosphere. The process of formation is different from that of the rest of the ionosphere and it can produce much higher electron densities, sometimes permitting oblique reflection of radio waves up to 150 MHz.
The mechanism for the oblique reflection of VHF waves from Es layers has not been well described, with candidates including specular reflection, scattering, and magneto-ionic double refraction. The polarization and fading characteristics of waves reflected from Es layers are proposed as a marker for the presence or absence of magneto-ionic effects.\ 
An experimental system has been developed for rapid and accurate polarization and fading measurements at 50 MHz. The overall sensitivity of the system has been optimized by reducing environmental electromagnetic noise, giving the ability to observe weak, short-lived Es propagation events. The effect of the ground reflection on observed polarization has been analyzed and the induced amplitude and phase biases compensated for.
A measurement campaign in the summer of 2018 gathered a large quantity of data, using amateur 50 MHz beacons, at distances between 1,000 km and 1,650 km, as signal sources. The results provide compelling evidence that Es-layer propagation at 50 MHz exhibits the characteristics of magneto-ionic double refraction, but the thin, intense and variable nature of the reflecting region means that the reflected signals can have quite extreme characteristics. Some of the results are surprising, and are yet to be explained convincingly.
In this presentation, an overview of the experimental technique will be given, and the results described. Some of this information has already been published, but much of it is new.

}, author = {Chris Deacon and Ben Witvliet and Cathryn Mitchell and Simon Steendam} } @proceedings {462, title = {Toward interpretation of HF propagation data obtained by the HamSCI Community - Ray Tracers and Ionospheric Models}, year = {2021}, month = {03/2021}, publisher = {HamSCI}, address = {Scranton, PA (Virtual)}, abstract = {

Perhaps one of the most pressing questions the Ham Sci community needs to address is how data obtained by the tangerineSDR or other platforms will be interpreted to obtain scientifically useful information.\  One approach is to produce an appropriate forward model describing the ionosphere and use ray tracers to convert that model into observables that are measured using SDRs.\  The purpose of this talk is to discuss these issues in general terms, but also to discuss simulation strategies that could be useful for the data collected by a network of radio amateurs.\  I will also present on the development of an open source python-based 3-D Jones Stephenson Ray tracer and other developments out of my laboratory that are relevant to ray tracing, including implementation using cuda and the development of point-to-point ray tracing.

}, author = {Stephen R. Kaeppler and Scott Driggers and Andrew Wetzel and Alexander Murtha and Tedi Godfrey} } @conference {391, title = {Let{\textquoteright}s Push the Exploration of the Ionosphere to The Next Level (Invited)}, booktitle = {HamSCI Workshop 2020}, year = {2020}, month = {03/2020}, publisher = {HamSCI}, organization = {HamSCI}, address = {Scranton, PA}, author = {T. Duffy} } @conference {383, title = {Observations and Modeling Studies of the Effects of the 2017 Solar Eclipse on SuperDARN HF Propagation}, booktitle = {HamSCI Workshop 2020}, year = {2020}, month = {03/2020}, publisher = {HamSCI}, organization = {HamSCI}, address = {Scranton, PA}, abstract = {

The total solar eclipses offer a unique opportunity to study the dependence of the ionospheric density and morphology on incident solar radiation. Unique responses may be witnessed during eclipses, including changes in radio frequency (RF) propagation at high frequency (HF). Such changes in RF propagation were observed by the Super Dual Auroral Radar Network (SuperDARN) radars in Christmas Valley, Oregon and in Fort Hayes, Kansas during the 2017 solar eclipse. At each site, the westward looking radar observed an increase in slant range of the backscattered signal during the eclipse onset followed by a decrease after totality. In order to investigate the underlying processes governing the ionospheric response to the eclipse, we employed the HF propagation toolbox (PHaRLAP), created by Dr. Manuel Cervera, to simulate SuperDARN data for different models of the eclipsed ionosphere. By invoking different hypotheses and comparing simulated results to SuperDARN measurements we could study the underlying processes governing the ionosphere and improve our model of the F-Region responses to an eclipse. This method was used in three studies to: identify the cause of the increase in the distance radio waves traveled during the eclipse; evaluate different models of change in eclipse magnitude over time; and investigate the effect of the neutral wind velocity on the simulated eclipse data. This presentation will discuss observations made by SuperDARN during the 2017 eclipse, major results from our raytrace studies, and unanswered questions that may be useful to consider when planning HamSCI{\textquoteright}s campaign and/or similar ionospheric studies for the next eclipse over the United States in 2024.

}, author = {M. Moses and L. Kordella and G. D. Earle and D. Drob and J. Huba and J. M. Ruohoniemi} } @conference {386, title = {Propagation Teepee: A High Frequency (HF) Radio Spectral Feature Identified by Citizen Scientists}, booktitle = {HamSCI Workshop}, year = {2020}, month = {03/2020}, publisher = {HamSCI}, organization = {HamSCI}, address = {Scranton, PA}, abstract = {

We report on the observations of a high frequency (HF) spectral feature that appears often in ground-based spectral data at 15-30 MHz.The feature, likely of terrestrial origin, is often recorded by a group of amateur radio astronomers, the Spectrograph User Group (SUG), whose main interest is in observing radio emissions from Jupiter. The feature appears as spectral enhancements with the frequency of enhancement first increasing and then decreasing with time, resulting in a {\textquotedblleft}triangular spectral feature.{\textquotedblright} Its shape is reminiscent of teepee tents (or TPs for short), the moveable dwellings of some groups of native-Americans. TPs usually have sharp or well-defined upper frequency limits for both the leading and trailing edges. While some TPs are observed in isolation, they are often seen in groups, distributed either in time or in frequency as a nested group at a particular time. Most TPs appear to be diffuse even at high time resolution, but a few TPs seen at high time resolution reveal that those TPs consist actually of discrete bursts, strongly suggestive that the band noise produced from lightning as possible radiation sources of the TPs. In this paper, we investigate the possible generation of TPs as a result of ionospheric reflection of band noise produced by remote lightning storms.

}, author = {S. F. Fung and D. Typinski and R. F. Flagg and T. Ashcraft and W. Greenman and C. Higgins and J. Brown and L. Dodd and A. S. Mount and F. J. Reyes and J. Sky and J. Thieman and L. N. Garcia} } @article {450, title = {Rapid and Accurate Measurement of Polarization and Fading of Weak VHF Signals Obliquely Reflected from Sporadic-E Layers}, journal = {IEEE Transactions on Antennas and Propagation}, year = {2020}, abstract = {

In the E-region of the ionosphere, at heights between 90 and 130 km, thin patches of enhanced ionization occur intermittently. The electron density in these sporadic-E (Es) clouds can sometimes be so high that radio waves with frequencies up to 150 MHz are obliquely reflected. While this phenomenon is well known, the reflection mechanism itself is not well understood. To investigate this question, an experimental system has been developed for accurate polarimetric and fading measurements of 50 MHz radio waves obliquely reflected by mid-latitude Es layers. The overall sensitivity of the system is optimized by reducing environmental electromagnetic noise, giving the ability to observe weak, short-lived 50 MHz Es propagation events. The effect of the ground reflection on observed polarization is analyzed and the induced amplitude and phase biases are compensated for. It is found that accurate measurements are only possible below the pseudo-Brewster angle. To demonstrate the effectiveness of the system, initial empirical results are presented which provide clear evidence of magneto-ionic double refraction.

}, keywords = {Brewster angle, ionosphere, radio noise, Radio wave propagation, VHF}, issn = {0018-926X}, url = {https://researchportal.bath.ac.uk/en/publications/rapid-and-accurate-measurement-of-polarization-and-fading-of-weak}, author = {Chris Deacon and Witvliet, Ben A. and Cathryn Mitchell and Simon Steendam} } @article {414, title = {The Rebirth of HF}, year = {2020}, month = {05/2020}, institution = {Rohde and Schwarz}, type = {White Paper}, address = {Munich, Germany}, abstract = {

HF stands for {\textquoteleft}high frequency{\textquoteright} and is usually used to refer to signals with frequencies in the range of 3 MHz to 30 MHz, although in many cases the practical definition of HF has be extended down to frequencies as low as 1.5 MHz. HF is also sometimes referred to, somewhat loosely, as {\textquoteleft}shortwave,{\textquoteright} especially in the context of broadcasting. These HF frequencies correspond to wavelengths in the range of approximately 10 to 100 meters. Given that modern homes contain Wi-Fi access points operating in the gigahertz range and that some 5G deployments are taking place in so-called millimeter-wave bands, the names {\textquotedblleft}high{\textquotedblright} frequency and "shortwave" may seem a bit misplaced, but it is worth nothing that the first experiments in long-distance radio communication by Marconi around the year 1900 used even lower frequency signals.

One of the best-known applications of HF is worldwide or global communications. Both government and commercial broadcasters can reach listeners worldwide using HF frequencies. This global reach is also extremely useful in many government and military applications, and HF is used extensively by amateur radio operators around the world. This paper will begin with an exploration of the unique properties of HF that enable global communications.

}, author = {Paul Denisowski} } @article {447, title = {Winter Sporadic-E-Like Propagation on 6 Meters}, volume = {76}, year = {2020}, month = {11/2020}, pages = {28-32}, abstract = {

The question was asked: why do we see sporadic-E like propagation in November and December, when many of the variables like UV radiation and solar exposure are at a minimum, unlike the very active sporadic-E summer months?\  Much like it was shown that North Atlantic transatlantic 6m propagation during the summer was made more possible by strategically placed weather storm systems, it looks like a similar effect with very strong jet stream boundaries also affect sporadic-E\ like communications during the winter months.\  This citizen science study is another example how amateur radio can contribute to science, and illustrates the great potentials for studies using ham radio data.\  We have many amateur radio stations on the air, using modes like FT8 which make contacts on propagation paths that we thought were previously impossible.\ 

}, url = {https://www.cq-amateur-radio.com/}, author = {Joseph A. Dzekevich} } @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 {360, title = {A Low-Cost Citizen Science HF Doppler Receiver for Measuring Ionospheric Variability}, booktitle = {American Geophysical Union Fall Meeting}, year = {2019}, month = {12/2019}, publisher = {American Geophysical Union}, organization = {American Geophysical Union}, address = {San Francisco, CA}, abstract = {

Advancement in understanding short term and small spatial scale ionospheric variability requires global high time and spatial resolution measurements. Professional ionospheric sounding networks are extensive and capable, yet more measurements are still needed due to the strongly magnetized nature and large extent of the ionosphere. High Frequency (HF, 3-30 MHz) radio signals are refracted by the ionosphere, and therefore are modulated by processes such as traveling ionospheric disturbances (TIDs) and geomagnetic storms. By measuring the amplitude and Doppler shift of trans-ionospheric HF signals, it is possible to detect signatures of ionospheric absorption and changes in propagation path length. We present a design for a low-cost citizen science HF multi-band receiver that measures the amplitude and Doppler shift of reference signals of opportunity from the US National Institute of Standards and Technology station WWV and the Canadian Institute for National Measurement Standards station CHU. The receiver will make 1 s cadence measurements on nine HF beacon frequencies and subsequently upload the results to a central server for scientific analysis. The local user will be able to review data daily, both locally and in aggregate on a web server, and participate in discussion of the ionospheric measurements. This receiver forms one component of the low-cost version of the Ham Radio Science Citizen Investigation (HamSCI) Personal Space Weather Station (PSWS), and is designed with the intention of distribution to hundreds to thousands of citizen science observers. Preliminary results from the prototype receiver will be presented.

}, url = {https://agu.confex.com/agu/fm19/meetingapp.cgi/Paper/602677}, author = {Kristina Collins and David Kazdan and John Gibbons and Aidan Montare and Skylar Dannhoff and Philip J. Erickson and Nathaniel A. Frissell} } @conference {296, title = {WWV Doppler Shift Observations}, booktitle = {HamSCI Workshop 2019}, year = {2019}, month = {03/2019}, publisher = {HamSCI}, organization = {HamSCI}, address = {Cleveland, OH}, author = {David Kazdan and Skylar Dannhoff and Aidan Montare and John Gibbons} } @article {261, title = {Simple and Accurate Variable Frequency RF Signal Generator}, journal = {QEX}, year = {2018}, month = {09/2018}, pages = {3-7}, chapter = {3}, abstract = {

This generator produces any frequency between 500 kHz and 40 MHz with an accu- racy approaching one part in 109, for example 0.01 Hz at 10 MHz. It uses an Arduino Nano, a GPS receiver with antenna, a digital encoder, a small TFT LCD color display, and the Silicon Labs Si5351A direct digital syn- thesizer (DDS). Together these parts cost me about $150. I will also share some interesting applications for this device.

}, issn = {0886-8093}, author = {Elwood Downey} } @conference {172, title = {Analysis of the August 2017 Eclipse{\textquoteright}s Effect on Radio Wave Propagation Employing a Raytrace Algorithm}, booktitle = {NSF CEDAR (Coupling, Energetics, and Dynamics of Atmospheric Regions)}, year = {2017}, month = {06/2017}, address = {Keystone, CO}, abstract = {

The upcoming total solar eclipse over the continental United States on August 21 offers an unique opportunity to study the dependence of the ionospheric density and morphology on incident solar radiation. There are significant differences between the conditions during a solar eclipse and the conditions normally experienced at sunset and sunrise, including the west-to-east motion of the eclipse terminator, the duration of the event, the solar zenith angle, and the continued visibility of the corona. Taken together, these factors imply that unique ionospheric responses may be witnessed during eclipses, as measured by changes in radio frequency (RF) propagation. High Frequency (HF) propagation varies greatly depending on ionospheric conditions. Hence, our analysis will include data collected during the eclipse by several HF systems shown in Figure 1 including SuperDARN, temporary radio transceiver sites, and amateur radio networks such as the Reverse Beacon Network (RBN) and Weak Signal Propagation Reporter Network (WSPRNet). The data analysis will be guided by raytrace models of HF propagation through an eclipsed ionosphere employing the HF propagation toolbox, PHaRLAP (created by Dr. Manuel Cervera).

}, author = {M. L. Moses and S. Burujupali and K. Brosie and S. Dixit and G. D. Earle and L. Kordella and N. A. Frissell and C. Chitale} } @conference {174, title = {HamSCI: The Ham Radio Science Citizen Investigation (Banquet Presentation)}, booktitle = {NSF CEDAR (Coupling, Energetics, and Dynamics of Atmospheric Regions)}, year = {2017}, month = {06/2017}, address = {Keystone, CO}, author = {N. A. Frissell and J. R. Ackermann and J. Dzekevich and G. D. Earle and P. J. Erickson and A. J. Gerrard and R. B. Gerzoff and S. W. Gunning and M. Hirsch and J. D. Katz and S. R. Kaeppler and R. W. McGwier and E. S. Miller and M. L. Moses and G. Perry and S. E. Reyer and A. Shovkoplyas and H. W. Silver and J. S. Vega and RBN Team} } @conference {163, title = {Ionospheric Impacts of the 2017 Total Solar Eclipse}, booktitle = {Dayton Hamvention}, year = {2017}, address = {Xenia, OH}, author = {Magalina Moses and Gregory Earle and Sushma Burujupalli and Nathaniel A. Frissell and Lee Kordella and Snehal Dixit and Charudatta Chitale and Xiayou Han} } @conference {218, title = {Practical investigation of the polarisation of 50MHz signals}, booktitle = {HamSCI-UK}, year = {2017}, month = {10/2017}, publisher = {HamSCI-UK}, organization = {HamSCI-UK}, address = {Milton Keynes, UK}, author = {C. Deacon} } @conference {162, title = {Upper Level Lows and Six Meter 50 Mhz Sporadic E}, booktitle = {Dayton Hamvention}, year = {2017}, address = {Xenia, OH}, abstract = {

Amateur radio is used to explore possible correlations between weather storm systems and sporadic E clouds to see if they are collocated. While some of the main causes of sporadic E propagation are wind shear, meteor strikes and upper atmospheric tides (ultimately coming from solar EUV energy inputs), radio operators have noticed that sporadic E propagation is also changed significantly by hurricanes and storms. \ Specific cases where K1YOW used amateur radio to investigate the effects of low pressure weather storms on the formation and/or enhancement of 6 meter sporadic E clouds are presented. DX Maps and earth wide weather model charts combined with operations on 6 meters are used to examine possible correlations between the location of the sporadic E clouds and the low pressure weather storm systems. \ Initial findings show a high degree of correlation when magnetic field strength is taken into consideration.

}, author = {Joseph A. Dzekevich and Philip J. Erickson} } @article {227, title = {Upper-Level Lows and 6-Meter Sporadic E}, volume = {101}, year = {2017}, month = {12/2017}, pages = {30-35}, abstract = {

Amateur radio is used to explore possible correlations between weather storm systems and sporadic E clouds to see if they are collocated. While some of the main causes of sporadic E propagation are wind shear, meteor strikes and upper atmospheric tides (ultimately coming from solar EUV energy inputs), radio operators have noticed that sporadic E propagation is also changed significantly by hurricanes and storms. \ Specific cases where K1YOW used amateur radio to investigate the effects of low pressure weather storms on the formation and/or enhancement of 6 meter sporadic E clouds are presented. DX Maps and earth wide weather model charts combined with operations on 6 meters are used to examine possible correlations between the location of the sporadic E clouds and the low pressure weather storm systems. \ Initial findings show a high degree of correlation when magnetic field strength is taken into consideration.\ \ 

}, issn = {0033-4812}, author = {J. Dzekevich} } @conference {144, title = {Characterizing the Ionosphere Using a Commercial Off the Shelf Software Defined Radio System}, booktitle = {Fall 2016 American Geophysical Union}, year = {2016}, month = {12/2016}, publisher = {American Geophysical Union}, organization = {American Geophysical Union}, address = {San Francsico}, abstract = {

On August 21, 2017, there will be a total solar eclipse over the continental United States (US). Solar eclipses offer a way to study the dependence of the ionospheric density and morphology on incident solar radiation. There are significant differences between the conditions during a solar eclipse and the conditions normally experienced at sunset and sunrise, including the east-west motion of the eclipse terminator, the speed of the transition, and the continued visibility of the corona throughout the eclipse interval. Taken together, these factors imply that unique ionospheric responses may be witnessed during eclipses including variations in the density and altitude of the F2 peak. In order to study these changes, we will establish four temporary field stations along the path of totality to track the maximum usable frequency (MUF) across the US over the course of the eclipse. Each field station shall consist of a commercial off the shelf (COTS) software defined radio (SDR) transceiver, a laptop computer running automatic link establishment (ALE) software, a Global Positioning System (GPS) receiver for timing, and a COTS antenna. Custom ALE software will automate the sites{\textquoteright} operation during the experiment to determine the MUF. As a validation test prior to the eclipse, we established three sites along the east coast to confirm that the SDRs are capable of inferring ionospheric conditions. The preliminary results characterize the effects of the sunrise/sunset terminator on our system{\textquoteright}s measurements as well as the change in foF2 during different seasons and under different geomagnetic conditions.

}, url = {http://hamsci.org/sites/default/files/publications/2016_AGU_Moses.pdf}, author = {Magdalina L. Moses and S. Dixit and Gregory D. Earle and Nathaniel A. Frissell and Lee Kordella and Xiaoyu Han and Charudatta Chitale} } @conference {53, title = {The Ionosphere{\textquoteright}s Pocket Litter: Exploiting Crowd-Sourced Observations}, booktitle = {Fall AGU - Oral Presentation}, year = {2015}, month = {12/2015}, publisher = {American Geophysical Union}, organization = {American Geophysical Union}, address = {San Francisco, CA}, abstract = {

One of the biggest challenges faced in developing and testing our understanding of the ionosphere is acquiring data that characterizes the latitudinal and longitudinal variability of the ionosphere. While there are extensive networks of ground sites that sample the vertical distribution, we have rather poor coverage over the oceans and in parts of the southern hemisphere. Our ability to validate the ionospheric models is limited by the lack of point measurements and those measurements that essentially constitute characterization of horizontal gradients. In this talk, we discuss and demonstrate the use of various types of crowd-sourced information that enables us to extend our coverage over these regions. We will discuss new sources of these data, concepts for new experiments and the use of these data in assimilative models. We note that there are new, low cost options for obtaining data that broaden the participation beyond the aeronomy/ionospheric community.

}, author = {Ethan S. Miller and Nathaniel Frissell and Stephen Kaeppler and Robert Demajistre and Andrew Knuth} }