[R-390] A vs non A

Randy and Sherry Guttery comcents at bellsouth.net
Tue Oct 9 14:26:54 EDT 2012


On 10/9/2012 11:33 AM, Robert Newberry wrote:

> I may be picking up up what I believe to be a R390. When I was talking to a
> friend about this he kinda scoffed saying they were less desirable and

Kinda Scoffed?  I believe I'd be looking a some other motive 
than "helping" you... several come to mind - none of which 
are very complimentary of your f

> harder to work on than the 390A.

 From a purist standpoint that is perhaps "fact", but 
barely. One of the design goals of the "A" was to simplify 
maintenance and mechanical issues - and there are certain 
things (such is maintaining sync in the tuning gears) that 
are "easier" in the "A" than non A.  That said - they are - 
in most people's opinion relatively minor - and are often 
out-weighed by the non-A's advantages.

 > Anything I should be looking out for on a 390?

It's "nice" if the "green gear" is present.  It's usually 
attached to the front of the geartrain by a  screw.  It's 
used to maintain gear sync during maintenance that requires 
getting into the RF deck, etc.  It's a convenience, not a 
"disaster" if not available.  Watch the heat in from the 
6082s (26.5V version of the 6080 - which itself is an 
industrial version of the 6AS7) - they run blistering hot. 
Otherwise - the things you'd look for in an "A" are the same 
in a non-A  (condition of geartrain, cams, slug racks;  
missing parts, etc.).

Things that should be replaced right off?

If the receiver has been in regular (recent) service, no.  
If not - I'd check the filter caps carefully. There isn't a 
"ticking time bomb" in a Non-A like there is in an "A" 
(specifically an original C553 in the "A").

 > Are parts harder to find on a 390 than they are on a 390A?

There were a lot more "A"s built than non-As - so yes some 
part are harder to find.  However - considering even the 
meters on an "A" are entering the realm of "unobtanium" - 
I'd hardly call that in and of itself an issue.

Should a 390 be avoided and continue looking for a 390A?

Absolutely!  You should also pass the contact info for it's 
current owner to me so I can "warn" them as well...   ;-)

Go for it!

-- 
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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