[ARC5] ARC5 Transmitter Calibration xtals

[Rick Nasti]

The ARC5 transmitters all used a built-in VFO to set the transmitting freq.
The octile based xtals were used with the 1629 magic eye tube to check the VFO freq by beating it against the xtal oscillator using the eye tube as a null indicator.
That's what the little mirror on the inside of the tube cover door was for.
Each transmitter used a different cal freq, which I think was near the center of the bandwith of the VFO.

I always thought it was a clever and somewhat elegant solution to the problem of keeping everyone on the same freq.

All of the above is based on 40 year old memories, but I believe it should be reasonably accurate.  

73,
Rick