I'm looking for information on a transceiver made by the Cubic Corporation- a Model TR-31. It is a small low- power radio that was used in something that flew in the '60s or '70s. I've seen a picture of one mounted behind the pilot's shoulder but I don't remember where I saw it or what it was installed in. It was something out of the ordinary- X-15, U-2, SR-71, Mercury capsule, etc. Does anyone know what it is and what it was used in?