[R-1051] R-1051 module identification

[Nick England]

The A model was manufactured by Elmer-Montedel in Italy.
Here's an internal photo - I can't find one of the front panel any more
http://www.radiomuseum.org/forumdata/users/6435/mil_R-1051/Fig2_a.jpg
and here's the A six-pack showing the 100Hz module
http://www.radiomuseum.org/forumdata/users/6435/mil_R-1051/Fig5_a.jpg

The original R-1051(plain) was manufactured in 3 runs so you will see
serial numbers staring with A, B, or C. There are some minor differences
but all of these were 500cps units - I have seen no evidence of a field or
depot conversion of these to 100cps. If you have a R-1051(plain) with a
100cps conversion please send me a photo - I'll be happy to learn something
new!

A new run of R-1051B contained the 100cps steps. This changeover to 100cps
channels was made on several pieces of USN HF gear, including the URC-32 to
URC-32B and the WRR-2 to WRR-2A.

The R-1051C model is the black face USAF version, otherwise same as the B.

Nick England K4NYW
www.navy-radio.com

On Mon, Oct 27, 2014 at 12:26 PM, David Wise <David_Wise at phoenix.com> wrote:

> The no-suffix R-1051 is 500Hz.  The R-1051A (Air Force?) and B (Navy?)
> went to 100Hz steps.
>