@proceedings {694, title = {Measuring Daily Ionospheric Variability and the 2023 and 2024 Solar Eclipse Ionospheric Impacts Using HamSCI HF Doppler Shift Receivers}, year = {2023}, month = {03/2023}, publisher = {HamSCI}, address = {Scranton, PA}, abstract = {

This project will study ionospheric variability across the continental United States (CONUS) generated by dawn/dusk transitions and two solar eclipses occurring in 2023 and 2024. Dawn and dusk produce a complex response in observed ionospheric variability that is still not completely understood. A network of Global Navigation Satellite System (GNSS) stabilized/synchronized high frequency (HF) receivers known as Grapes will be used for the study. Thirty Grape receivers will be deployed throughout North America to optimize the study of the ionospheric impacts simultaneously received from two locations. Additional stations will be funded by the HamSCI amateur radio community. This project will generate observations to answer the scientific questions: (1) How do dawn and dusk ionospheric variability vary with local time, season, latitude, longitude, frequency, distance, and direction from the transmitter? (2) Is eclipse ionospheric response symmetric with regard to the onset and recovery timing? (3) How similar is the eclipse to the daily dawn and dusk terminator passage? (4) Would multipath HF mode-splitting in the post-eclipse interval be similar to dawn events? (5) Would the response be different for two eclipses?

This project is part of the Ham Radio Science Citizen Investigation (HamSCI) program and will be open to volunteers who want to field instruments and contribute to scientific analysis and discussion. This project will also establish a new network of DASI instruments that, due to its low cost and operation by volunteers, has the potential to provide measurements for years to come. This project will support students (undergraduate, MS and Ph.D.).

}, author = {Rachel Boedicker and Nathaniel Frissell and Kristina Collins and John Gibbons and David Kazdan and Philip J. Erickson} } @article {736, title = {Measuring the Frequency Accuracy and Stability of WWV and WWVH}, volume = {107}, year = {2023}, month = {03/2023}, pages = {33-37}, abstract = {

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

}, issn = {0033-4812}, author = {Michael A. Lombardi} } @proceedings {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 {705, title = {Modeling the Ionosphere with SAMI3 (Invited Tutorial)}, year = {2023}, month = {03/2023}, publisher = {HamSCI}, address = {Scranton, PA}, abstract = {

SAMI3 (Sami3 is Also a Model of the Ionosphere) is a global, comprehensive model of the ionosphere/plasmasphere system. It is based on the SAMI2 model developed at the Naval Research Laboratory (Huba et al., 2000). SAMI3 models the plasma and chemical evolution of seven ion species (H, He, N, O, N, NO and O). The ion temperature equation is solved for three ion species (H, He and O) as well as the electron temperature equation. Ion inertia is included in the ion momentum equation for motion along the geomagnetic field. The neutral composition and temperature can be specified by empirical models (e.g, NRLMSISE00, HWM14) or by first-principle atmosphere models (e.g., TIEGCM, WACCM-X, HIAMCM). SAMI3 uses a nonorthogonal, nonuniform, fixed grid. The grid is designed to optimize the numerical mesh so that the spatial resolution decreases with increasing altitude. SAMI3 can use an untilted or tilted dipole model of earth{\textquoteright}s magnetic field, or an IGRF field model based on the Richmond apex model. A general overview of ionospheric physics and the SAMI3 model will be presented, as well as several applications of the code.

}, author = {Joseph Huba} } @proceedings {650, title = {Magnetosphere-Ionosphere Coupling Studies Using the PSWS Magnetometer Network}, year = {2022}, month = {03/2022}, publisher = {HamSCI}, address = {Huntsville, AL}, abstract = {

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

}, author = {Hyomin Kim and Sadaf Ansari and Julius Madey and David Witten and David Larsen and Scotty Cowling and Nathaniel Frissell and James Weygand} } @proceedings {619, title = {Mid-latitude Irregularities Observed by the Oblique Ionosonde Sounding Mode for the HamSCI Personal Space Weather Station}, year = {2022}, month = {03/2022}, publisher = {HamSCI}, address = {Huntsville, AL}, abstract = {

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

}, author = {Dev Raj Joshi and Nathaniel A. Frissell and Juha Vierinen} } @proceedings {610, title = {Modeling ionograms with Deep Neural Networks: Applications to Nowcasting}, year = {2022}, month = {03/2022}, publisher = {HamSCI}, address = {Huntsville, AL}, abstract = {

The state parameters of the ionosphere are of fundamental importance not only for space weather studies but also for technological applications such as satellite radio communications. As with many geophysical phenomena, the ionosphere dynamics are governed by nonlinear processes that make ionospheric forecasting a challenging endeavor. However, we have enormous datasets and ubiquitous experimental sources that can help us find the complex regularities in these phenomena. We forecasted ionograms for different solar activity times and database sizes using regression deep neural networks. Due to the neural network{\textquoteright}s extrapolation of virtual heights for all frequencies given to the model, we estimated foF2 using two embedded different models to identify the last frequency of each ionogram. Furthermore, we made hyperparameter tuning for each training set applying the k-fold cross-validation method. The predictions were compared to measurements collected with the Digisonde system at the Jicamarca Radio Observatory, a persistence model, IRI, and the SAMI2 model estimations. Finally, we will present preliminary results on a new virtual heights model that predicts the difference between consecutive ionograms and preliminary results from a model to estimate electron densities.

}, author = {Jhassmin Aricoch{\'e} and Enrique Rojas and Marco Milla and Reynaldo Rojas} } @proceedings {599, title = {Moonbased Ham Repeater Station Project}, year = {2022}, month = {03/2022}, publisher = {HamSCI}, address = {Huntsville, AL}, abstract = {

Just as Jules Verne dreamed that man would one day reach the Moon, many radio amateurs have thought of having an amateur radio repeater on our natural satellite. Why not lay the theoretical foundations to reach this end and be able to detect the tasks to be solved? Let{\textquoteright}s try to calculate and design a repeater station and an earth station that are capable of communicating with each other and that are affordable for the average ham pocket. Today it cannot be done, but what about in 50 years?

}, author = {Carlos Mascare{\~n}as} } @proceedings {565, title = {Magnetometer Alignment Techniques Using LocalHost}, year = {2021}, month = {09/2021}, publisher = {ARRL-TAPR}, address = {Virtual}, url = {https://youtu.be/MHkz7jNynOg?t=8248}, author = {Engelke, William D.} } @proceedings {566, title = {Magnetometer Board RFI Testing (Proceedings)}, year = {2021}, month = {09/2021}, publisher = {ARRL-TAPR}, address = {Virtual}, url = {https://youtu.be/MHkz7jNynOg?t=9172}, author = {Engelke, William D.} } @proceedings {458, title = {Mid-latitude Irregularities in the Early Results from the Ionospheric Sounding Mode Using Chirp Ionosondes of Opportunity for the HamSCI Personal Space Weather Station}, year = {2021}, month = {03/2021}, publisher = {HamSCI}, address = {Scranton, PA (Virtual)}, abstract = {

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

}, author = {Dev Joshi and Nathaniel A. Frissell and William Liles and Juha Vierinen and Ethan S. Miller} } @conference {376, title = {Magnetometer Support for the Personal Space Weather Station and Related Projects}, booktitle = {HamSCI Workshop 2020}, year = {2020}, month = {03/2020}, publisher = {HamSCI}, organization = {HamSCI}, address = {Scranton, PA}, abstract = {

The Personal Space Weather Station project requires the use of a high performance, yet affordable, ground based magnetometer component. Here we describe the design and testing of a magnetometer support module for that purpose. A sufficiently cost effective magnetometer offers the opportunity to capture new science by allowing construction of large and well populated grids of instruments. The module chosen makes use of sensor components based on magneto-inductive effects. Many types of magnetometer exist, all trading cost for performance across a huge range. Our goal was to design a sensitive instrument around commercially available components that would be versatile and low enough in cost to allow its deployment in novel ways.

}, author = {D. Witten III and F. Bonte and H. Kim} } @conference {306, title = {Meteor scattering communication using JS8CALL and its possibilities}, booktitle = {HamSCI Workshop 2019}, year = {2019}, month = {03/2019}, publisher = {HamSCI}, organization = {HamSCI}, address = {Cleveland, OH}, author = {Nagakura, Dai} } @conference {286, title = {A Modular SDR for HamSCI and Other Users}, booktitle = {HamSCI Workshop 2019}, year = {2019}, month = {03/2019}, publisher = {HamSCI}, organization = {HamSCI}, address = {Cleveland, OH}, abstract = {

This presentation covers some actual hardware that can be used to fulfill the requirements of the HamSCI Personal Space Weather Station project. A new modular hardware architecture is proposed that will fulfill the requirements not only of PSWxS users, but possibly of Phase 4 Satellite Ground Station, academic research, experimenter and general SDR users as well.

}, author = {Scotty Cowling} } @conference {338, title = {Moonbounce Via the MIT Remote Linked EME Station}, booktitle = {Dayton Hamvention}, year = {2019}, month = {05/2019}, publisher = {Ham Radio 2.0}, organization = {Ham Radio 2.0}, address = {Xenia, OH}, author = {Marty Sullaway} } @conference {277, title = {Modeling Amateur Radio Soundings of the Ionospheric Response to the 2017 Great American Eclipse}, booktitle = {Fall AGU}, year = {2018}, month = {12/2018}, publisher = {American Geophysical Union Meeting}, organization = {American Geophysical Union Meeting}, address = {Washington, DC}, abstract = {

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

}, keywords = {Amateur Radio, Citizen Science, Ham Radio, HF propagation, ionosphere, solar eclipse}, url = {https://agu.confex.com/agu/fm18/meetingapp.cgi/Paper/418915}, author = {Frissell, N. A. and Katz, J. D. and Gunning, S. W. and Vega, J. S. and Gerrard, A. J. and Earle, G. D. and Moses, M. L. and West, M. L. and Huba, J. D. and Erickson, P. J. and Miller, E. S. and Gerzoff, R. B. and Liles, W. and Silver, H. W.} } @article {248, title = {Modeling Amateur Radio Soundings of the Ionospheric Response to the 2017 Great American Eclipse}, journal = {Geophysical Research Letters}, volume = {45}, year = {2018}, month = {05/2018}, type = {Research Letter}, abstract = {

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

}, issn = {1944-8007}, doi = {https://doi.org/10.1029/2018GL077324}, url = {https://doi.org/10.1029/2018GL077324}, author = {N. A. Frissell and J. D. Katz and S. W. Gunning and J. S. Vega and A. J. Gerrard and G. D. Earle and M. L. Moses and M. L. West and J. D. Huba and P. J. Erickson and E. S. Miller and R. B. Gerzoff and W. Liles and H. W. Silver} } @conference {221, title = {Magnetometers and Riometers}, booktitle = {HamSCI-UK}, year = {2017}, month = {10/2017}, publisher = {HamSCI-UK}, organization = {HamSCI-UK}, address = {Milton Keynes, UK}, author = {F. Honary} }