[R-390] A vs non A

[Cecil]

As I remember all IFs were not setup to be stagger tuned.  There were caps across the IF transformers to increase the Q in either the ones that the manufacturer designed to be or not to be....I can't remember.  The thought was that those that were intended to be, we're electrically different to maintain spec.  Stager tuning one that was not intended to be would probably have low IF gain...and not stagger tuning one that was designed to be would probably have excessive IF gain.

I've always wondered how one tells the difference...short of looking for the caps.

Was this just an "A" thing or was there both in the earlier R-390 series as well.

Of course maybe this is all myth...

Cecil

Sent from my iPad

On Oct 15, 2012, at 7:51 PM, Raymond Cote <bluegrassdakine at hotmail.com> wrote:

> Right SINS tech--like I was. Another world. You are right about working only on NAV. equipment. A friend had a A model when he lived in Agat south of the base and that was when we tried to stagger time the 390-a with staggering it. If I remember am signals were a little better but that was 42 years ago. 
>     When my bench is back up and ready I will try again just for drill and test the BW before and after. I forget why we were doing it in C school at Great Lakes. 
> 
> Thanks for the response. 
> 
> Raymond Cote
> 1466 Townline Rd
> Steward Ill 60553
> 808-341-8213
> """""""""""""""""""""""""""""""""""
> Human beings are passionately attached to their beliefs by interests  
> that have nothing to do with the truth. 
> 
> On Oct 15, 2012, at 15:36, "Randy and Sherry Guttery" <comcents at bellsouth.net> wrote:
> 
>> On 10/15/2012 12:55 AM, Raymond Cote wrote:
>> 
>>> Randy! Did you do any staggering on the tender?
>> 
>> First  - never officially* worked on an R-390/A during my time on Proteus.  Besides - as far as "staggering"  on the Tender - Unless it was prescribed in the official documentation, not a chance. Have a problem with a receiver not done "by the book"?? - heaven help the poor SOB that's involved with that!
>> 
>> * I was a Nav ET - (SINS specifically) - we had nothing to do (officially) with Comm gear aboard ship - there were regular ETs for that.  Sherry and I had a lot of comm gear over the years as a hobby - but I didn't "officially" touch a Navy 390/A until I was helping my charges study for advancement at Naval Weapons Station, York Town, VA.
>> 
>> That said - while aboard Proteus - i.e. 1971 - 1975 - we had a number of 390s - (25+) so sure - Sherry and I staggered tuned my R-391 and her R-390 just to see what - if any - difference we could "hear".  In our opinion - no where near enough "results" to be worth the effort...   And considering the IF in an "A" - figured the results would be even less impressive...    so never tried.
>> 
>> 
>> Best regards...
>> 
>> -- 
>> randy guttery
>> 
>> A Tender Tale - a page dedicated to those Ships and Crews
>> so vital to the United States Silent Service:
>> http://tendertale.com
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