[Milsurplus] Designations

[KD7JYK DM09]

"Actually there is no such thing as an R-390A. There is only an R-390A/URR."

I had some of each.  Some made by Collins, some by Motorola, with 
documentation that matched the nomenclature.  Additionally, the radios 
had slightly different controls, and those without the dataplates could 
be determined at a glance, just by what knobs were on them, and what 
those knobs controlled.  For example, some had a certain number of 
positions, and functions, and the "same knob" on another, had a 
different number of functions, and positions.  Unless one of the 
companies dropped the /URR off the dataplates, and paperwork, there was 
at least the A, and A/URR.  I don't know of any further designations, as 
I only owned those models.  I no longer have the radios, I sold them in 
the mid-90's to buy a car, however, I still have a manual for one, and 
with a little luck, it's for the "no such thing" model.  Will let the 
group know, when I find it.

Kurt