How to work SSB satellites

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 145 MHz, 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 radio 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. If adjusting for Doppler shift manually try tuning the radio on the highest frequency band while while keeping the radio on the lower frequency band constant. See The One True Rule for Doppler Tuning https://www.amsat.org/wordpress/wp-content/uploads/2015/02/FDT-WA4SCA.pdf

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 ceased operation but the same principles apply to other satellites with linear transponders such as  AO-73 (FUNcube-1), FO-29 and OSCAR-7.

Chertsey Radio Club – Getting started with SSB satellites
http://chertseyradioclub.blogspot.co.uk/2017/03/ssb-ham-radio-satellites-beginners-guide.html

Satellite Tracking https://amsat-uk.org/beginners/satellite-tracking/

John Heath G7HIA’s article  ‘Getting started on amateur radio satellites’ can be downloaded from
https://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

VUSAT OSCAR 52 (HAMSAT) Information