What were these receivers? I found a single page of photo and some specs. I do not know the publication source, but it says

Change 5  April 1972     B.R. 2414 ( 1 )

Receiver CJA consists of receiver 5820-99-916-4679    and   synthesizer frequency  5820-99-916-4675

Receiver CJC  is the receiver only. 
Not clear to me but looks like CJC receiver has an actual HFO which can be locked to the synthesizer.  No manufacturer listed. Looks like receiver basic does have a slide rule

type dial. Who was this, FAA ?

-Hue Miller

Newport, Oregon