[R-390] R390/390A really "classified"

[kellerfamily01 at charter.net]

I was in the USAFSS in the 1950s, which was the Air Force version of
the ASA. Our main reason for existing was to provide military support
for the NSA. We did a lot of interesting things that probably should
not be talked about even today. But, when we were on intercept duty in
the operations shack, we had an R390A and a Hammarlund SP-600 in front
of us. We used the SP-600 to search around for comit related to the
mission and, when we found something, we would lock it in with the
R-390A to copy. Bill WB5KXO