The Telemetry System switched eight channels of information into an audio oscillator whose output modulated both transmitters.
The eight telemetry channels were: 0: HI identification 1: Battery current drain 2: X axis horizon sensor 3: Battery voltage 4: Y axis horizon sensor 5: Internal temperature 6: X axis horizon sensor 7: Skin temperature The HI keyer transmitted the traditional amateur radio operator's greeting, Hi, in morse code. Each channel was sampled for 6½ seconds for a 52 second telemetry cycle. The audio frequencies ranged from 400 Hz to about 3 kHz. For each of the battery voltage, current and temperature telemetry channels, except zero, there was a calibration graph provided in the Users' Guide to convert the audio frequency into the parameter being measured. |