The Amateur Radio on the International Space Station (ARISS) packet digipeater aboard the ISS has been active for several days now on 437.550 MHz. The UHF frequency means users will have to make adjustments for Doppler on both uplink and downlink.
The change to 70 centimeters comes in the wake of a problem that has sidelined the Ericsson VHF transceiver, so the UHF model has been put into service. The digipeater operates just as it did when it was on its former 145.825 MHz frequency.
AMSAT suggests that users program a group of five memory pairs to permit an operating range that will compensate for Doppler, with transmit frequencies from 437.560 to 437.540 MHz, and receive frequencies from 437.540 to 437.560 MHz, in 5 kHz increments (i.e., the transceiver would be in simplex for 437.555 MHz).
More information is available from the AMSAT Station and Operating Hints page. Scheduled ARISS contacts and APRS operations will also utilize the Ericsson UHF transceiver in the Columbia module. — Thanks to AMSAT News Service
The HERON 1000 is a solid state amplifier for use in 1.8 MHz to 50 MHz bands. The RF section is Consisting of an amplification unit (HF 1000 P) capable of delivering a power of 1200 watts peak and 1000 watts In continuous service (FM). The... Read more
Introducing the W8AMZ 80–6m OCF / Windom Multi-Band Antenna using a 4:1 Balun and rated for 2 KW. The SWR is generally below 1.5:1 on 6, 10, 20, 40... Read more
Baofeng UV-5R Hello all! K5CLC here to share a really crazy and extreme field test I did on my year old Baofeng UV5R, to test its merit under the most... Read more
“Radio Frequency Interference (RFI) Pocket Guide” by Kenneth Wyatt, WA6TTY and Michael Gruber, W1MG This small 88-page spiral bound (3” x 5”) pocket g... Read more