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AMATEUR RADIO

Radio signals provide a window into the Personal Space Weather station
changing ionosphere. The various signals Through HamSCI, radio amateurs and researchers are bridging this gap by designing
from WWV, reflecting off the ionosphere, hardware for a distributed network of personal space weather stations (PSWSs),
undergo changes in path length as the accessible to professional and amateur scientists alike. These stations come in two
ionospheric electron density profile changes. varieties: a low-cost model and a more powerful, software-defined radio TangerineSDR,
This results in changes to the observed a wideband receiver that can be reconfigured for a range of experiments. At the core of
frequency of radio signals at receiving both is a single-board computer, which interfaces with a set of modular instruments
points, akin to the rise and fall in pitch of a (e.g., a magnetometer) and uploads data to a central database.
passing train whistle. These stations are in the prototyping and testing stage, with plans to deploy a
Comparing the received radio signal network of PSWSs in the next 3 years in time to record the upcoming 2024 solar eclipse
with a precision local frequency standard, across North America. As the Moon’s shadow travels across Earth’s surface, it will
such as a GPS-disciplined oscillator, allows shield the radio stations below from solar extreme ultraviolet radiation, providing an
a user to measure these ionospherically excellent opportunity to collect baseline radio data. We hope to have the network up and
induced frequency shifts. This running in time for Festival of Frequency Measurement 2024, and we invite radio
measurement is prepared and recorded amateurs to join in as volunteer scientists to help improve our understanding of Earth’s
with open-source software. space environment. n
Numerous data sets recorded
simultaneously from multiple locations offer Acknowledgments
information, when these data sets are This research is supported by National Science Foundation grants AGS-2002278,
examined both individually and collectively, AGS-1932997, and AGS-1932972. The authors thank all HamSCI collaborators,
about the ionosphere at the time the data are particularly those at the Tucson Amateur Packet Radio Association, MIT Haystack
taken. This information includes the Observatory, the University of Scranton, the New Jersey Institute of Technology, and
movements of traveling ionospheric the Case Amateur Radio Club (W8EDU).
disturbances and other important
phenomena at various scales. References
WWV was never intended to provide - Frissell, N. A., et al. (2018), Modeling amateur radio soundings of the ionospheric
these data, but the station’s exceptional response to the 2017 Great American Eclipse, Geophys. Res. Lett., 45(10),
precision, high power and guaranteed 4,665–4,674, https://doi.org/10.1029/2018GL077324.
continuous availability, make it a perfect - Kazdan, D., et al. (2019), A low-cost HamSCI citizen science HF Doppler receiver for
beacon. Thanks to the advent of inexpensive measuring ionospheric variability, Abstract SA43C-3213 presented at Fall Meeting
GPS-disciplined oscillators and single-board 2019, AGU, San Francisco, Calif., 9–13 Dec.,
computers, amateur scientists can assemble https://agu.confex.com/agu/fm19/meetingapp.cgi/Paper/602677.
complete prototype systems to collect such
data for less than $200, or they can build
systems from existing equipment. Thus, the About the authors
amateur community, mobilised on a national Kristina Collins (kd8oxt@case.edu; call sign KD8OXT) and David Kazdan (AD8Y),
scale, can generate a large-scale, novel data Case Western Reserve University, Cleveland, Ohio; and Nathaniel A. Frissell
set for ionospheric study. (W2NAF), University of Scranton, Scranton, Pa.

Low-cost personal space weather stations (PSWS) are designed primarily for measurements of time standard stations, such as WWV
and the Canadian station CHU. More powerful software-defined radio (SDR) PSWS systems can be reconfigured for a range of
experiments. Credit: Nathaniel Frissell

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