[R-390] R390A Turns Counter BFO option?

[rbethman]

I have a Litton Industries BFO counter, NOS/NIB.

I'd be highly interested as to what other modification is needed to 
expand the BFO range from 6Kc to 26Kc.

Bob - N0DGN

On 3/13/2011 2:08 PM, Nick England wrote:
> FWIW -From "Cryptologic Collection Equipments" NAVEDTRA 10251 (1977)
> http://www.navy-radio.com/manuals/crypto-equip.htm
>
> BFO PITCH.-The BFO PITCH control
> varies the output frequency of the BFO above
> and below 455kHz. The normal R-390A BFO is
> designed to vary by 3kHz above and below
> 455kHz. Many of the R-390A receivers with
> which you will come into contact have a
> modified BFO pitch control, called a
> MICRODIAL. This modification enables the
> BFO to be varied over a 26kHz range (13kHz
> above and below 455kHz.)
>
> cheers,
> Nick K4NYW
> www.navy-radio.com