[R-390] What to buy...

Sat Jul 30 05:00:21 EDT 2005

Thanks for taking the time to answer that question Cecil. That was very
good read. I guess the fact that I don't have any experience with either
model I should have asked "Which model would be better for a beginner?"
That said, I think that I'm going to go ahead and get one from Dave. He
is offering up a good deal on a 390.

Sandy I think you put that in perspective with your Chevy analogy. I can
sure see the differences in those two body styles.

Thanks for the Links Don. Great stuff! It seems that the 390's are
extremely popular. There is quite a bit of info out there.

I can say one thing about this list. It is by far one of the better
radio related lists that I have been on. Thanks for the help guys.

Tracy

-----Original Message-----
From: Cecil Acuff [mailto:chacuff at cableone.net] 
Sent: Saturday, July 30, 2005 8:31 AM
To: Tracy Fort
Subject: Re: [R-390] What to buy...

Hi Tracy,

        Well that question is going to draw a good bit of fire from a
few.

In my opinion and I think you will find most of the guys opinion there
is 
not any real way of telling who made your radio by looking at the front 
panel.  Here's the drill.  During the life of your radio it periodically

went back to a depot somewhere that completely disassembled it for
overhaul. 
The modules were scattered amongst the modules from two dozen other
radio's. 
I guess guys and gals trained in specific modules were sitting daily 
rebuilding IF decks for example.  The rebuilt modules would go in a
finished 
module pile.  Meanwhile the front panel was refinished along with the
knobs. 
What I didn't mention was that early in the process the front panel tag
was 
removed and placed in a bin with two dozen others as well.

Once the front panel, chassis and knobs were all cleaned up and
reassembled 
the tech would go and grab a full complement of modules from the
completed 
module bins and start dropping them back in the radio...with no regard
for 
manufacturer....because that's how the R-390A was designed.  All 
manufacturers worked from the same military specifications so the
modules 
were all interchangeable.

Once the radio was reassembled, lubed and aligned back to specifications

they grabbed a tag from the tag bin and screwed it down to the front 
panel...

That's why the guys call them "Depot Dawgs"

So....it might say Motorola on the tag but have an EAC IF deck, an
Amelco RF 
deck, a Motorola power supply, a Collins PTO and a Teledyne Audio deck.

Occasionally one will find a radio with matching modules and front panel

tag.  I have a couple like that.  Some may have never been through
depot.  I 
have a Motorola from the 56 contract that appears to be that way.  Is it

more valuable...probably not.

The only thing that seems to make one more valuable is if they are all 
Collins.  There are guys out there that will only own or buy one that is
all 
Collins.  Purists I guess.  Are they any better....well some will argue
that 
the build quality is different between the manufacturers....I've only
seen 
minor differences.  Certainly the EAC's from the 67 contract are the
newest 
of the line and should be in the best shape but it all depends on the
life 
it lived.

Also many others will tell you that the most used radio's are probably
the 
best....I tend to agree with them to a point.  Well used means it was 
probably dependable and worked well.  Pristine coming out of surplus may

mean it was a depot queen.  Was broke all the time and never saw much
time 
being operated....

If one had a problem that nobody could seem to crack it would be shoved
over 
in the corner for years.

I have read stories about a guy picking up a radio from a hamfest or
surplus 
dealer that was in beautiful shape only to find it didn't work properly
and 
after many many hours of work a cable was found to be pinched between
some 
parts of the chassis...probably on original assembly.

I believe all radios can be made to work as designed with enough
work....

I currently have probably 10 or 12 R-390A's waiting for restoration.  I
am 
just about to finish an R-390/URR for a list member that will be sold on

Ebay.  Should bring $1200 to $1300.  It's beautiful and in an original 
military cabinet.  All refinished and electrically restored.

That brings us to the question of the R-390 -vs- R-390A.  Both are
excellent 
radio's.  The R-390 was only built by Collins and Motorola.  They are 
becoming very difficult to find but the prices don't seem to reflect the

scarcity.  I expect that to change in the near future.  The difference 
between the two radio's is minor functionally.  The "A" uses mechanical 
filters in the IF, the R-390 uses tuned circuits of inductors and 
capacitors. It's not as selective but has better audio quality on AM/SW 
broadcasts.  It does have some heat related problems in the voltage 
regulators that bakes a few resistors...but it has very few capacitor 
problems because the radio's were built with all top quality components.

The "A" was a redesigned R-390 to reduce the manufacturing cost and to 
simplify field maintenance.  The result was a radio that was easier to 
service but was built with cheaper components...mostly caps.  It uses
molded 
paper caps instead of the metal with glass sealed caps that don't fail
very 
often....even nearly 55 years later.   The "A" caps fail quite
often....but 
gradually where the owner is not really aware due to gradually reduced 
performance.  Occasionally they will fail and burn a resistor or kill a 
tube.
Pull an easy module from your radio and use a magnifying glass an give a
few 
of the molded caps a look...near the seams on the sides you will find
cracks 
a times that run the length of the cap....Not a good thing.

Many guys own an R-390A restored to top performance and maybe add a few 
minor mods to improve performance...then they also own something like a 
Hammarlund SP-600 fully restored to tune around with.  Once they find a 
target with the SP they will bring it up on the R-390A to bring it out
of 
the noise and apply the mechanical filters to make listenable....Then we

seem to buy several more of each just for the fun. (it's an untreatable 
illness)  I think at last count I have 4 SP-600's with maybe 3 or 4 more
on 
the way.  It's my favorite radio.

I also have 8 or 10 R-1051 radio's.  They replaced the R-390 series.  I
was 
doing restorations on them as a small business for a few years but
interest 
in them seemed to die and I couldn't even break even on the work so I
closed 
up shop on that work.  Plan to sell them off as is to clear the shop of 
them.  They are very difficult radio's to work on but when right are
super 
SSB receivers....

Hope all this helps a bit....

Don't let the guys get you down...some of them can be somewhat of a pain
at 
times but there is a lot of good info that comes out of this group...I
like 
the dynamics myself!

Cecil....
----- Original Message ----- 
From: "Tracy Fort" <beerbarrel at cox.net>
To: <R-390 at mailman.qth.net>
Sent: Friday, July 29, 2005 10:39 PM
Subject: [R-390] What to buy...

>
>
> Are certain manufacturers better than others? For instance, is Collins
> better than Motorola? Or does it really matter?
>
> Is a 390 better than a 390a? Or is that another case of it does not
> really matter?
>
> Thanks for the answers,
>
> Tracy
>
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