The SSB/CW linear transponder amateur radio satellites such as VO-52 are great fun to work but the technique required is different to that used for the FM satellites.
Simon 2E0HTS has produced a video showing how to make contacts through VO-52.
Using a home-made 10 element 435 and IO Loop for 145MHz, with a Yaesu FT-847. Simon – 2E0HTS, adjusts his (uplink) transmitted signal to correct the Doppler of the received (downlink) frequency whilst talking to fellow Ham operators around Europe. Thanks to the stations worked via the VO-52 satellite which were SP9FPP, PD0HF and SP6DCO.
Watch How To Make A VO-52 SAT QSO
Most linear satellites use what are known as ‘Inverting Transponders’ to reduce the Doppler shift. You transmit lower sideband (LSB) on the uplink and it appears as upper sideband (USB) on the downlink.
When working through linear transponders use as little power as possible, this will help extend the lifetime of the transponder and satellite batteries. As a guide ensure your downlink signal is no stronger than the satellite beacon. Low duty cycle modes such as SSB and CW are recommended.
The band plan for linear satellite downlinks is similar to what you’d expect on the HF bands with CW operation in the lower part of the downlink and SSB in the rest. Current satellite status can be seen at http://oscar.dcarr.org/
Since this video was made VO-52 has changed over to its Dutch SSB/CW transponder and now uses these frequencies:
Uplink: 435.2250 – 435.2750 MHz SSB/CW
Downlink: 145.9250 – 145.8750 MHz SSB/CW
Beacon: 145.8600 MHz CW
N2YO Online Real Time Satellite Tracking http://www.n2yo.com/
John Heath G7HIA’s article ‘Getting started on amateur radio satellites’ can be downloaded from http://amsat-uk.org/beginners/radcom-getting-started-on-satellites/
David A Palmer, KB5WIA, has written an article “Twins! A Backpack-Portable Full Duplex Satellite Station with Dual FT-817ND’s” that can be seen at http://kb5wia.blogspot.com/2010/10/satellite-portable-station.html