[R-390] What to buy...

[Bob Young]

  Hi Cecil,

  I read your post with interest, I don't often post except top ask questions as I don't own a 390 yet, but do own a HQ-180. I noticed you said that the SP-600 was your favorite receiver and I have noticed other people saying the same thing. Why are they better than a 180 in your opinion? On paper it would seem that the 180 is the better receiver having triple conversion etc, they are on my list of wanted radios though along with several different Collins and 390A's, thanks

  Bob Young


  -----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....