The TRD-20 Tone Receiver/Decoder (TRD) is a rack mount radio frequency
(RF) receiver that will display the presence of any of the 20 individual
tones or combination command tones. The unit was designed to conform with
the requirements set forth in the IRIG Standard 313-01 of the RCC (Range
Commanders Council) and to detect and display up to six tones simultaneously.
The rear panel connections include RF input, Signal Strength, and Decoded
Channel outputs of the 20 tone detector circuits.