I bought a Hammarlund SP-600-JX26 yesterday at a hamfest. While searching around a little for variations between the different versions, lot numbers, etc., I found some info on other military receivers that are interesting.
Specifically, the SP-600, R-388, R-390, R-390A, & R-392 are hugely popular receivers. But, I never see anything about the AN/FRR-22 & An/FRR-23. These are general-coverage receivers (but no AM or 160m) made by RCA with 29 tubes (!) from the early '50s. They seem to have some interesting features (6 filter positions, dimmer control on the front-panel lights, 2 headphone jacks, separate volume control for headphones, etc.)
I found a pic at:
http://www.navy-radio.com/rcvrs/images/frr22-01.JPGAnyone have one of these receivers or know why they don't seem to be for sale? Were they much more expensive than the R-390As and SP-600s of the day? Did they have a design flaw?
Thanks & have a great day!
Andrew