The first shot above shows a "classic" (though very dated, even in 1967) set of equipment used for 850 CPS-shift radio teletype (RTTY). All of the point-to-point HF trunks used space diversity, a radio architecture by which two antennas fed two seperate receivers. Looking at the second vertical equipment bay from the left, below the two speakers on top is antenna "A" R-390 receiver, identifiable by the two large black knobs and mechanical frequency readout in the center; then antenna "A" CV-89 teletype convertor (demodulator); below this, in mismatched-gray paint is antenna "B" CV-89, below which is antenna "B" R-390 receiver. Below the lower R-390 is a CM-22A signal comparator, that selected the best of the two signals processed by this equipment
|