TY - Generic T1 - Broadband Recordings from Medium Wave DXers Could Support Solar Eclipse Science T2 - HamSCI Workshop 2023 Y1 - 2023 A1 - Nicholas Hall-Patch AB -

Medium wave DXers monitor the AM broadcast band (535-1705kHz) to receive distant radio stations, generally between sunset and sunrise, in order to take advantage of favorable ionospheric conditions then.  Historically, these DXers have been aware of similarly favorable reception conditions that occur during solar eclipses, and during the 2017 solar eclipse, a number of them recorded the entire AM broadcast band using software defined radios (SDRs).  During the upcoming annular and total solar eclipses, it is proposed to suggest to such DXers that their pursuit of distant radio stations be done in such a way as to make their recorded IQ files of optimum use to propagation researchers, both from HamSCI and from elsewhere, by documenting such things as receiver, software  and antenna settings,  and by making sure that timestamps in their data are as accurate as possible.  DXers could also be encouraged  to make additional recordings of sunrise and sunset conditions in order to support HamSCI scientific goals.  Because some DXers use SDRs with system clocks locked to GPS, the data from such SDRs could be useful as a lower frequency adjunct to data gathered from Grape v2, especially if Doppler variation of specific broadcaster’s carriers could be converted to the audio format used by Grape v2, before further processing.  IQ data recorded during the eclipse could be gathered together and archived by HamSCI for future researchers, such as was done for the 2017 eclipse.  The processing of such data to support present HamSCI scientific objectives could require significant volunteer effort, however.

JF - HamSCI Workshop 2023 PB - HamSCI CY - Scranton, PA ER - TY - Generic T1 - Broadband Loop Antennas and Preamplifiers for Receiving VLF to HF T2 - HamSCI Workshop 2022 Y1 - 2022 A1 - David McGaw A1 - Mike Trimpi A1 - James LaBelle AB -

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

JF - HamSCI Workshop 2022 PB - HamSCI CY - Huntsville, AL ER - TY - Generic T1 - Beacon Programme to study inland Tropo in South Africa T2 - HamSCI Workshop 2021 Y1 - 2021 A1 - Hans van de Groenendaal A1 - Brian Jacobs AB -

On the West Coast of South Africa contacts via Tropospheric ducting with St Helena Island occur regularly and are generally well predicted on the Hepburn charts. While some sporadic tropospheric conditions inland have resulted in long distance two metre contacts they mostly occurred by accident, someone just happens to be on the air. A few years ago, the South African Radio League (SARL) embarked on a beacon programme with the aim to study Tropospheric and other propagation modes on VHF. It was planned to link the beacon programme with a reverse beacon monitoring system. It turned out that CW beacons are not particularly useful as the reverse beacon monitoring system requires a fairly strong signal to identify the beacon signal. This defeated the objective of the study. The SARL has now opted for a next generation beacon system of which the first one will go on the air during March 2021. AMSAT SA is partnering with the SARL and has launched a crowd funding initiative to generate more funding to accelerate the process and erect more beacons and expedite a reverse beacon network. The paper will introduce the objectives of the programme, the challenges of being at the southern point of Africa, details of the next generation beacon system and the development of a reverse beacon monitoring system.

JF - HamSCI Workshop 2021 PB - HamSCI CY - Scranton, PA (Virtual) UR - https://hamsci2021-uscranton.ipostersessions.com/?s=74-34-37-9E-AA-7E-F5-CF-CF-FD-00-3F-96-71-A9-0E ER - TY - CONF T1 - Balloon Pico Races T2 - Dayton Hamvention Y1 - 2019 A1 - William Brown JF - Dayton Hamvention PB - Ham Radio 2.0 CY - Xenia, OH ER -