@proceedings {1042, title = {An Amateur Radio HF Channel Sounder}, year = {2026}, month = {03/2026}, publisher = {HamSCI}, address = {Newington, CT}, abstract = {This presentation will provide a description of a channel sounding architecture that is accessible to the amateur radio community. It is used to study selected radio channels between an HF transceiver and a remote software-defined radio receiver. A system has been implemented that employs a combination of a Flex 6700 SDR transceiver and a remote Kiwi SDR. An audio file containing a series of a repeated maximum-length sequence is transmitted over the air by a Flex 6700 transceiver to a selected Kiwi SDR that generates an audio recording of the received signal. The recording is sent back to the transmitting station over the Internet for post processing. A software analysis tool is used to cross correlate the original transmitted audio file with the received signal recording. This process generates a multiple-period channel impulse response, which is used to construct a channel impulse response matrix. The channel impulse response matrix provides the basis for quantifying channel characteristics such as delay, Doppler, and time variability. This system has been used to perform a series of over-the-air tests in the 60 m amateur band and selected Kiwi SDRs. This presentation will describe the system architecture, signal generation and processing, validation using audio baseband channel simulators, and over-the-air measurements. Measurement results from a sporadic-E event that occurred on June 21, 2025 will be highlighted. This system should be useful for citizen science efforts to study solar events and for intercomparisons with other measurement techniques. The waveforms developed in this effort might be highly useful for incorporation into the WWV special tests waveform, and it might facilitate some very interesting propagation measurements and studies.}, author = {Robert Johnk} } @proceedings {1026, title = {Analyzing Meteor Scatter Communications Through Citizen Science and Data Driven Methods}, year = {2026}, month = {03/2026}, publisher = {HamSCI}, address = {Newington, CT}, abstract = {Meteor scatter communication is a radio propagation technique that exploits ionized trails produced by meteoroids as they enter Earth{\textquoteright}s atmosphere, enabling brief long-distance radio contacts. As meteors enter the Earth{\textquoteright}s atmosphere, they produce ionized trails which amateur radio operators utilize to bounce signals off, enabling short bursts of long-distance communication. This research investigates the historical growth, practical impact, and physical principles of the effect meteor scatter has on radio communication. Taking advantage of major meteor scatter events, including the Perseids and Geminids, data was collected during organized Meteor Scatter QSO Parties (MSQP). Amateur radio citizen scientists study ionospheric propagation by making contacts using meteor trails using diverse equipment and the WSJT-X digital communication software. The collected data sets from everyone containing a mixture of meteor scatter signals, aircraft scatter, and other propagations are compiled and submitted to an online public database for approval. To deal with the immense amount of data, a machine learning program was created to filter and classify data as meteor scatter events. This research indicates the usefulness of machine learning to isolate events within large scale data sets while gaining a deeper understanding of utilizing meteor induced ionization and its role in radio propagation.}, author = {Nina Tormann} } @proceedings {1028, title = {Assessment of a Low-Cost Magneto-Inductive Magnetometer for Personal Space Weather Stations}, year = {2026}, month = {03/2026}, publisher = {HamSCI}, address = {Newington, CT}, abstract = {Low-cost ground-based magnetometers are an important component of Personal Space Weather Station (PSWS) efforts, yet their performance in urban residential environments remains poorly constrained. This work investigates how nearby homes and urban electromagnetic interference influence the noise floor of the RM3100 magneto-inductive magnetometer. Four short-duration measurements were conducted at two locations within a residential property to examine this question. At each location, magnetic field data were collected using a pipe-based apparatus and within a shielded cage, resulting in four experimental configurations. Each measurement spanned approximately one week, producing a total of four weeks of data. Noise characteristics and signal stability are compared across locations and shielding conditions to evaluate the hypothesis that shielding reduces environmental interference and that RM3100-based systems deployed in urban settings can provide data suitable for PSWS applications. By characterizing the limitations and practical considerations of residential magnetometer deployments, this work supports the use of low-cost instrumentation in citizen science, amateur radio{\textendash}driven space weather studies, and distributed ground-based monitoring networks relevant to both community participants and the broader space physics community.}, author = {Daniel Clancy and Hyomin Kim and Nathaniel Frissell and Rachel Frissell and David Witten} } @proceedings {1029, title = {An Atlas of Forms Seen on HF Personal Space Weather Station Traces, to Help Users Recognize and Analyze Events}, year = {2026}, month = {03/2026}, publisher = {HamSCI}, address = {Newington, CT}, abstract = {

The ionosphere and our high frequency communications probing it are complicated. We are writing an atlas of forms to aid people in recognizing and understanding things seen on GRAPE/WSPRDaemon traces. Examples include a solar eclipse, a CME hitting theEarth{\textquoteright}s magnetosphere, a solar flare, and two-hop side scatter. Entries would be categorized by date as well as by type of event. Users are encouraged to submit puzzling examples to be considered by a content review team. We propose that this atlas be added to the HamSCI website. Further, we seek to expand this effort by encouraging contributions from operators of all types of Personal Space Weather Stations in the HamSCI network.

}, author = {Robert Mattaliano and Gwyn Griffiths and Dave Swartz and Mary Lou West and Gary Mikiti} } @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 {932, title = {Analysis of the HamSCI Solar Eclipse High Frequency Time Difference of Arrival Experiment Observations Using Automated Techniques}, year = {2025}, month = {03/2025}, publisher = {HamSCI}, address = {Newark, NJ}, abstract = {

The objective of our research is to use narrowband linear audio pulses, which are sensitive to time displacement, and transmit them through High Frequency (HF) commercial off-the-shelf (COTS) single-sideband (SSB) amateur radios to measure changes in ionospheric reflection heights, specifically during a solar eclipse. This will be accomplished and automated using programming techniques learned in the Digital Signal Processing course at the University of Scranton, where the primary objective is to use TDOA (Time Difference of Arrival), a technique that measures the time displacement of single/multiple paths as they reach a receiving station. These TDOA values will be manipulated using a virtual height model that will yield different values of ionospheric layer heights based on the locations of the receiving and transmitting stations. During the October 2023 and April 2024 solar eclipses, WA5FRF transmitted a series of linear audio pulses (chirps) every 10{\textendash}15 minutes to various receiving stations on the 5, 7, and 14 MHz amateur radio bands. Received signals were squared and filtered to detect the waveform envelope. Correlation with a matched signal was then used to identify the start time of each chirp, after which a Fast Fourier Transform (FFT) was used to identify the beat-note frequency generated by multipath propagation. The October 2023 eclipse automated analysis shows that the F region reflection point was raised from 262.5 km at 17:00 UTC to 300 km at eclipse maximum at 17:30 UTC. The April 2024 eclipse analysis shows no real maximum reflection point; however, it does indicate an increase in layer height following maximum obscuration at 18:30 UTC. Both analyses are in good agreement with the hmf2 observations of the Austin Ionosonde. The intended purpose was to monitor multipath interference for 1{\textendash}2 hops off of the F2 layer; however, recent developments in this automated process yield additional data for other modes.

}, author = {Alexandros Papadopoulos and Gerard Piccini and Nathaniel Frissell and Steve Cerwin and Jesse McMahan and Paul Bilberry and Blackshear Samuel and Aidan Montaigne and Kristina Collins and Robert Spalletta} } @proceedings {933, title = {Approaches to Identifying Medium Wave Signal Enhancements in HamSCI{\textquoteright}s Solar Eclipse Data}, year = {2025}, month = {03/2025}, publisher = {HamSCI}, address = {Newark, NJ}, abstract = {

During the solar eclipses of 2023 and 2024, \ HamSCI organized 27 volunteers in six countries to record the entire medium wave band (525-1705kHz) using software defined radios (SDRs), both during the eclipse and for the same time period on other days, as well as during dawn and dusk periods. \ Well over 20TB of Medium Wave SDR data was submitted to HamSCI as a result.\ 

For both eclipses, all data has now been preprocessed using visualization software to generate waterfall displays of AM broadcasters{\textquoteright} carriers at 0.1Hz resolution for each of the 117 domestic broadcast channels. \ This will allow researchers to quickly pick out signal enhancements during the eclipse periods for further study. \ HamSCI is in the process of making the enhanced data available publicly via Zenodo.\ 

Some participants{\textquoteright} data displayed hundreds of these enhancements. \  Readable audio from various AM broadcasters was heard for a short time during the eclipse, but many enhancements were of AM broadcasters{\textquoteright} carrier waves only. \  As hearing a station identification in the enhanced signal{\textquoteright}s audio is the easiest way to determine the location of a station{\textquoteright}s transmitter, what can be done to identify those signals that do not contain identification in the audio, or were not strong enough to deliver audio at all?

This presentation will suggest encouraging radio listening hobbyists to "DX the data" available at Zenodo in order to deliver as many station identifications as possible from the audible data. \  In addition, ways will be suggested to characterize the carriers of AM broadcasters across data sets in ways to otherwise identify transmitter locations.

This will help provide HamSCI with a higher quality data set, more suitable for assisting in verifying ionospheric models, particularly those that are simulating the effects of solar eclipses.

}, author = {Nicholas Hall-Patch} } @proceedings {960, title = {Are Weak Type II Radio Bursts Associated with Shocks Driven by Coronal Mass Ejections?}, year = {2025}, month = {03/2025}, publisher = {HamSCI}, address = {Newark, NJ}, abstract = {

Type II radio bursts are a type of slow-drifting solar radio bursts, usually understood as radio signatures from shocks driven by coronal mass ejections (CMEs).\  Most previous studies on type II radio burst have focused on strong and bright type IIs, which, when imaged, have been often found to be associated with CME-driven shocks, although a few exceptions have also been reported. It remains an outstanding question whether such an association also holds for very weak type II radio bursts. Taking advantage of the imaging spectroscopy capabilities of the Owens Valley Radio Observatory{\textquoteright}s Long Wavelength Array (OVRO-LWA) with an extremely high sensitivity, we identified several weaker type II radio burst events in 15{\textendash}88 MHz, and then analyzed them using radio interferometric imaging as a function of time and frequency. Weak type II radio bursts were categorized as being less than 10 minutes in total duration with low flux (\<10 s.f.u). We located the radio emission source and characterized their shape, brightness, and spatial-temporal variation. Then, using white light and multi-band extreme ultraviolet imaging observations, we tracked their possible solar drivers. We found that some weak type II radio burst events were not associated with a typical white light CME, but with a small scale coronal disturbance within a coronal streamer. For other type IIs, we could not find any visible activity from EUV and white light. All weak type IIs do not show a clear shock front counterpart. We discuss implications of our findings in understanding the formation of type II radio bursts.

}, author = {KresUranNu Baylor and Peijin Zhan and Bin Chen} } @proceedings {826, title = {Analysis of changes to propagation and refraction height on specific paths induced by the 14 October 2023 eclipse}, year = {2024}, month = {03/2024}, publisher = {HamSCI}, address = {Cleveland, OH}, abstract = {

Signal and noise levels, alongside precise frequency and frequency spread measurements were collected by over 20 WsprDaemon stations prior to, during, and after the October 2023 eclipse using FST4W digital mode. By combining fortuitous home locations with eclipse-specific portable operations, augmented with multiband transmitters at selected sites, the group has gathered a rich data set over 3.5 MHz to 28 MHz. Path geometry includes along- and across-eclipse, from 10s km to over 5000 km. Different geometries, path lengths and frequencies have enabled quantitative analysis of eclipse-induced propagation changes. Reduced D region absorption resulted in 7-9 dB increase in propagated-in noise on 7 MHz at KPH/KFS. The triangular form of the noise anomaly contrasted with a flat-topped +13-15 dB signal level anomaly on 3.57 MHz on a 466 km path. Reduced F2 layer critical frequency (foF2) resulted in several phenomena on 14 MHz identified via frequency spread changes. Two-hop propagation reverted to one-hop on an 1808 km path. On a 1055 km path one-hop changed to an above-the-basic MUF mode - two-hop sidescatter - with signal levels 30 dB lower. Reduced foF2 affected two-hop along-eclipse paths of 4400 km to 5000 km from Costa Rica to Nevada and California on 28 MHz. At ca. 4400 km signals were lost twice, as the second hop, then the first, were affected, with recovery between. Signals at 5000 km were not completely lost. Simple ray-trace modelling to match the observations suggested effective sunspot number (SSNe) had dropped from 125 to ~70. As stations were GPS-disciplined or GPS-aided precise Doppler shift measurements at two-minute intervals with 0.1 Hz resolution were obtained. On a 545 km path Doppler shift at 3.57 MHz, 7 MHz and 10.14 MHz were converted to path velocities and, integrated back and forward in time from a single F2 layer height from the Pt. Arguello ionosonde, gave a credible diurnal profile of refraction height. Compared to 15th October the 14th showed a triangular-shaped height anomaly with a maximum of +33 km. These and other results illustrate the effectiveness of path-specific analysis of FST4W data for eclipse studies.

}, author = {Gwyn Griffiths} } @proceedings {858, title = {Analysis of the HamSCI Solar Eclipse High Frequency Time Difference of Arrival Experiment Observations Using Automated Techniques}, year = {2024}, month = {03/2024}, publisher = {HamSCI}, address = {Cleveland, OH}, abstract = {

The objective of our research is to analyze the effects of a solar eclipse on High Frequency (HF) radio by extracting the time difference of arrival (TDOA) due to multiple ionospheric paths of ~3 kHz bandwidth chirp signals sent and received with unmodified commercial off-the-shelf (COTS) single sideband (SSB) amateur radio transceivers. We use programming techniques learned in the Digital Signal Processing course at The University of Scranton in the Python language to automate this process. On the day of the 14 October 2023 eclipse in Texas, WA5FRF transmitted a series of chirps every 15 minutes to receiving stations N5DUP and AB5YO on 5.3 MHz and 7.2 MHz. Received signals were digitized, then squared and low-pass filtered to detect the waveform envelope. Correlation with a matched signal is then used to identify the start time of each chirp, after which a Fast Fourier Transform (FFT) is used to identify the beat-frequency (and TDOA value) generated by the multipath propagation. This TDOA value is then used to compute an ionospheric reflection height. On the WA5FRF-N5DUP path, this analysis shows that the F region reflection point raised from 262.5 km at 17:00 UTC to 300 km at eclipse maximum at 17:30 UTC and then returned to approximately 280 km at 18:00 UTC. This result is in good agreement with the hmF2 observations of the Austin ionosonde.

}, author = {Alexandros Papadopoulos and Gerrard Piccini and Thomas Pisano and Nicholas Guerra and Matthew Felicia and Evan Hromisin and Aidan Montare and Kristina Collins and Paul Bilberry and Samuel Blackshear and Steve Cerwin and Nathaniel A. Frissell} } @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} } @article {988, title = {April 2024 eclipse: the effect on transatlantic HF propagation}, volume = {100}, year = {2024}, month = {12/2024}, pages = {36-38}, type = {General Interest}, abstract = {

The total eclipse on 8 April 2024\ began over the eastern Pacific,\ traversed North America, passed over Newfoundland, and ended at sunset over the eastern Atlantic. Despite\ its seeming remoteness from the UK, this eclipse was a rare opportunity to assess the effects of a\ ionospheric ionisation on the well-used\ transatlantic propagation path.

}, url = {https://hamsci.org/sites/default/files/publications/G3ZIL_Solar_Eclipse_RadCom_Dec24.pdf}, author = {Griffiths, G} } @proceedings {854, title = {ARDC - 44Net and Grants}, year = {2024}, month = {03/2024}, publisher = {HamSCI}, address = {Cleveland, OH}, abstract = {

Amateur Radio Digital Communications provides funding through grants for Amateur Radio related projects and has 12 million static and routable IPv4 addresses.\  In this presentation you will shown how to apply for and use these resources in your research projects.

}, author = {John Hayes} } @proceedings {879, title = {Automated Methods for Studying Long Scale Ionospheric Disturbances and Climatology}, year = {2024}, month = {03/2024}, publisher = {HamSCI}, address = {Cleveland, OH}, abstract = {

During the last year we have been pushing forward with improving our methods for detecting and studying Large Scale Ionospheric Disturbances (LSTIDs) using amateur radio spots from the RBN, WSPR, and PSK databases. We now have automated systems in place to collect and archive these data daily. We developed a way to detect the minimum useful range and extract a curve from that; we can then use a Fast Fourier Transform (FFT) to estimate the period, amplitude, and occurrences of these LSTIDs, leading to an improvement in our capability to study the climatology (long term trends) of these waves in plasma density.

}, author = {William D. Engelke} } @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 {725, title = {Amateur Radio Through the Ages (Exhibit)}, year = {2023}, month = {03/2023}, publisher = {HamSCI}, address = {Scranton, PA}, abstract = {

Amateur Radio Through the Ages Exhibit is an exhibit of historical amateur radios, QSL cards, QST magazines, and radio accessories on display at the University of Scranton Loyola Science Center / Hope Horn Gallery during the Spring 2023 semester. This exhibit is presented by the Murgas Amateur Radio Club K3YTL, The University of Scranton Amateur Radio Club W3USR, and The University of Scranton Department of Physics and Engineering, especially Tom Mayka W3TRM, Bill Gallagher WA3RA, Herb Krumich K2LNS, Ian Kellman K3IK, Phil Galasso K2PG, Elaine Kollar K3VQR, Dave Kirby N3SRO, Dr. Darlene Miller-Lanning, and Dr. Nathaniel Frissell W2NAF.

}, url = {https://photos.app.goo.gl/68gA9i32piVyM9C59}, author = {Tom Mayka and William Gallagher and Herb Krumich and Ian Kelleman and Phil Galasso and Elaine Kollar and Dave Kirby and Darlene Miller-Lanning and Nathaniel A. Frissell} } @proceedings {692, title = {Analyzing Large Scale Traveling Ionospheric Disturbances using Spot Data and Curve Fitting}, year = {2023}, month = {03/2023}, publisher = {HamSCI}, address = {Scranton, PA}, abstract = {

Large Scale Traveling Ionospheric Disturbances can be observed in amateur radio data by plotting and analyzing the propagation of signals from RBN, WSPR and PSK. One of the goals of these analyses is to determine the period and amplitude of these disturbances, which are visible to the human eye in the plotted data, but are challenging to accurately characterize for period and amplitude. (Such data is important for ionospheric climatology studies).\  Earlier research (Frissell, 2016, https://doi.org/10.1002/2015JA022168) has used a spectral approach to this analysis; this presentation shows a curve fitting technique which may prove easier to use for the large volume of analysis necessary for climatology studies.

}, author = {William D. Engelke} } @proceedings {645, title = {An Algorithm for Determining the Timing of Components within the HamSCI-WWV/WWVH Scientific Test Signal}, year = {2022}, month = {03/2022}, publisher = {HamSCI}, address = {Huntsville, AL}, abstract = {

Beginning in November 2021, WWV and WWVH radio stations have been broadcasting a test signal developed by a Ham Radio Science Citizen Investigation (HamSCI) working group to study what additional ionospheric measurements can be gleaned from the WWV/WWVH transmitter beyond carrier Doppler shift and time-of-flight of standard timing pulses. The signal consists of various individual components including tones, chirps, and Gaussian noise bursts [1]. Interested operators record the signal data at their location, providing researchers with the data naturally manipulated in many different ways [2]. This project seeks to precisely identify the timing of each signal component in the recorded data. The algorithm involves passing the data through various software filters to remove unwanted elements such as frequencies outside of range of interest, DC offset, and so on. Correlation is then performed between the recorded data and each original component to produce their timing. The performance of the algorithm itself is estimated by calculating the SNR of each received signal and the corresponding confidence interval of the algorithm. The results can help to explain the broken symmetry between the transmitted signal and the received signal.

References
[1] Lombardi. {\textquotedblleft}Radio Station WWV.{\textquotedblright} NIST, 16 Nov. 2021, https://www.nist.gov/pml/time-and-frequency-division/time-distribution/radio-station-wwv.
[2] Pamela.corey@nist.gov. {\textquotedblleft}WWV/WWVH Scientific Modulation Working Group.{\textquotedblright} NIST, 5 Nov. 2021, https://www.nist.gov/pml/time-and-frequency-division/time-services/wwvwwvh-scientific-modulation-working-group.

}, author = {Cuong Nguyen and Tyler Jordan and Joseph Tholley and Vaibhavi Patel} } @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 {615, title = {Autonomous Ground Magnetometer Station Using DRV425 Fluxgates}, year = {2022}, month = {03/2022}, publisher = {HamSCI}, address = {Huntsville, AL}, abstract = {

We have developed a prototype ground magnetometer station that uses 3 Texas Instrument fluxgate-on-a-chip DRV425 sensors. The design is low cost and uses a particle photon or particle electron microprocessor (IOT device) with either wifi or cellular connectivity to process and transmit data. We will present data from a prototype installation in Athabasca/CA that is located near a high-quality science grade fluxgate (ATH) for comparison. We would like to deploy several 10s of these devices with the help of the HAMSCI community for science and space weather applications at no cost to the operators. However, the operators would have to commit to install the stations and tend to them as necessary. The effort would be funded through a major funding agency. At this meeting we would like to gauge the interest among HAM radio operators for such a project.

}, author = {Joachim Raeder and Juan-Carlos Bautista and Michael Hirsch} } @conference {586, title = {Amateur Radio Communications as a Novel Sensor of Large Scale Traveling Ionospheric Disturbances (Invited)}, booktitle = {American Geophysical Union Fall Meeting}, year = {2021}, month = {12}, publisher = {American Geophysical Union}, organization = {American Geophysical Union}, address = {New Orleans, LA}, abstract = {

Amateur (ham) radio high frequency (HF) communications are routinely observed by automated receiving systems on a quasi-global scale. As these signals are modulated by the ionosphere, it is possible to use these observations to remotely sense ionospheric dynamics and the coupled geospace environment. In this presentation, we demonstrate the use of these data to observe Large Scale Traveling Ionospheric Disturbances (LSTIDs), which are quasi-periodic variations in F region electron density with horizontal wavelengths \> 1000 km and periods between 30 to 180 min. On 3 November 2017, LSTID signatures were detected simultaneously over the continental United States in observations made by global HF amateur radio observing networks and the Blackstone (BKS) SuperDARN radar. The amateur radio LSTIDs were observed on the 7 and 14 MHz amateur radio bands as changes in average propagation path length with time, while the LSTIDs were observed by SuperDARN as oscillations of average scatter range. LSTID period lengthened from T ~ 1.5 hr at 12 UT to T ~ 2.25 hr by 21 UT. The amateur radio and BKS SuperDARN radar observations corresponded with Global Navigation Satellite System differential Total Electron Content (GNSS dTEC) measurements. dTEC was used to estimate LSTID parameters: horizontal wavelength 1136 km, phase velocity 1280 km/hr, period 53 min, and propagation azimuth 167{\textdegree}. The LSTID signatures were observed throughout the day following ~400 to 800 nT surges in the Auroral Electrojet (AE) index. As a contrast, 16 May 2017 was identified as a period with significant amateur radio coverage but no LSTID signatures in spite of similar geomagnetic conditions and AE activity as the 3 November event. We hypothesize that atmospheric gravity wave (AGW) sources triggered by auroral electrojet intensifications and associated Joule heating are the source of the LSTIDs, and discuss possible reasons why LSTIDs were observed in November but not May.

}, url = {https://agu.confex.com/agu/fm21/meetingapp.cgi/Paper/822746}, author = {Frissell, Nathaniel A. and Sanchez, Diego F. and Perry, Gareth W. and Kaeppler, Steven R. and Joshi, Dev Raj and Engelke, William and Thomas, Evan G. and Coster, Anthea J. and Erickson, Philip J. and Ruohoniemi, J. Michael and Baker, Joseph B. H.} } @conference {538, title = {Antarctic SuperDARN Observations of Medium Scale Traveling Ionospheric Disturbances}, booktitle = {NSF CEDAR (Coupling, Energetics, and Dynamics of Atmospheric Regions)}, year = {2021}, month = {06/2021}, publisher = {CEDAR}, organization = {CEDAR}, address = {Virtual}, 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. MSTIDs are typically associated with atmospheric gravity waves (AGWs). Statistical studies of MSTIDs using Super Dual Auroral Radar Network (SuperDARN) radars in the Northern Hemisphere have shown strong correlation with Polar Vortex activity, while a study of MSTIDs using the Antarctic Falkland Islands SuperDARN radar showed populations of MSTIDs with signatures suggestive of both solar wind-magnetosphere coupling sources and lower neutral atmospheric winds sources. The sources of the MSTIDs are still not well understood, and there are limited studies of MSTIDs using SuperDARN radars in the Southern Hemisphere. We present initial results of MSTID observations of using Antarctic SuperDARN radars, including the radar at McMurdo Station.

}, author = {Francis Tholley and Nathaniel A. Frissell and Joseph B. H. Baker and J. Michael Ruohoniemi and William Bristow} } @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 {397, title = {An Aurorasaurus Citizen Science Database of Strong Thermal Emission Velocity Enhancement (STEVE) Observations (ePoster)}, booktitle = {HamSCI Workshop 2020}, year = {2020}, month = {03/2020}, publisher = {HamSCI}, organization = {HamSCI}, address = {Scranton, PA}, abstract = {

For many years, amateur aurora observers have reported on unique subauroral aurora or aurora-like structures which they could not classify at first. Later, these structures also puzzled the scientific community. In 2016 members of the Alberta Aurora Chasers Facebook group introduced the name STEVE for these structures. Very recently in 2018 and 2019, first scientific publications have been published linking these subauroral structures with the subauroral ion drift (SAID). Since then the backronym Strong Thermal Emission Velocity Enhancement is used in the scientific literature for this phenomenon. The underlying ionospheric processes are still not understood in every detail. Although highly likely STEVE observations have been reported sporadically since nearly the end of the Maunder Minimum their specific character had been almost overlooked for a long time until citizen scientists working with Aurorasaurus started to put a closer view on them and contacted the scientific community reaching for answers to all their questions. A freely accessible event list for worldwide image supported amateur STEVE observations was missing for a long time. The presented work is part of a non-funded volunteer project and has been performed with the aim to fill this gap. STEVE observations posted in Aurora related social media groups but also on aurora observer websites have been analyzed to prepare the list on the basis of data use standards and fair use. The outcome is a list summarizing more than 790 single observations, observations with time for 150 days and 178+ observation days in total. In its current version the event list covers the period January 1999 to December 2019. This presentation gives an overview for the content and development of the list, and briefly summarizes possible analyzes that can be performed based on the content of the event list and how it already supports and furthers the research on the STEVE phenomenon. This work presents an example of how data from citizen scientists can support highly topical space science research.

}, author = {Michael Hunnekuhl and Elizabeth MacDonald} } @conference {392, title = {Aurorasaurus: Citizen Science Observations of the Aurora (Invited Tutorial)}, booktitle = {HamSCI Workshop 2020}, year = {2020}, month = {03/2020}, publisher = {HamSCI}, organization = {HamSCI}, address = {Scranton, PA}, author = {E. MacDonald} } @conference {310, title = {Affordable Scientific Grade Ground Magnetometer (Demonstration)}, booktitle = {HamSCI Workshop 2019}, year = {2019}, month = {03/2019}, publisher = {HamSCI}, organization = {HamSCI}, address = {Cleveland, OH}, author = {Hyomin Kim} } @conference {301, title = {ARISS: Talking to the astronauts via ham radio and how it inspires students}, booktitle = {HamSCI Workshop 2019}, year = {2019}, month = {03/2019}, publisher = {HamSCI}, organization = {HamSCI}, address = {Cleveland, OH}, abstract = {

The ARISS (Amateur Radio on ISS) program is an international consortium of amateur radio organizations and space agencies such as the National Aeronautics and Space Administration (NASA). Their goal is to allow students worldwide to talk to the International Space Station (ISS) astronauts with the hopes of inspiring students to pursue interests in science, technology, engineering, and math (STEM) while introducing them to amateur radio. The NASA Glenn Amateur Radio Club (NGARC) in collaboration with the NASA Space Communication and Navigation (SCaN) at NASA Glenn Research Center helped the Girl Scouts of North East Ohio (GSNEO) make contact with the ISS astronauts using ARISS. The specific activities undertaken by each of these organizations will be discussed starting from the proposal selection, throughout planning to the eventual contact the Girl Scouts made with the ISS astronauts. In addition, this presentation will discuss how schools and youth organizations are able to utilize the ARISS radio contact to enhance their educational objectives to support not only STEM goals but also other areas like foreign languages, geography, music and the arts. The space station, as it travels around the Earth, is a perfect way to discuss not only orbital mechanics but geography to students, while the questions asked by students allow them to learn about science concepts based on responses from the astronauts to their specific science questions. As the time from proposal selection to the actual contact could be up to a year, schools and youth organizations are able to engage all age groups in this year-long preparation as well as plan activities with their local community. Together the end result is to ultimately help students make a 10-minute contact with the ISS astronauts that is unforgettable for all in attendance.

}, author = {Nancy R. Hall} } @conference {216, title = {Amateur Radio in the 21st Century}, booktitle = {HamSCI-UK}, year = {2017}, month = {10/2017}, publisher = {HamSCI-UK}, organization = {HamSCI-UK}, address = {Milton Keynes, UK}, author = {S. Nichols} } @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 {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} }