AvtechTyee?s CTS-700 ramp test set tests ICAO standard SELCAL decoding
systems, HF and VHF radio systems, audio systems, and ATSCALL or DTMF
selective calling decoders that reside on the aircraft. Battery-powered
and totally independent of ground facilities, the CTS-700 generates the
RF and tone signals needed to activate the system under test.