There hasn't been amateur satellite activity on
the HF bands since the Russian RS-10/11 and RS-12/13 satellites went silent in
the late 1990s and early 2000s, respectively. Now, China's AMSAT organization –
CAMSAT – is planning to launch two satellites this fall, one of which will
bring satellite communication back to HF. According to AMSAT-UK, CAS-5a is slated to include an HF/HF transponder and an HF/UHF transponder as well as an HF beacon and VHF/UHF linear and FM transponders. The second satellite, CAS-6, will have a UHF/VHF linear transponder as well as an atmospheric wind detector.
