Ivy Iverson wrote in a message to Bruce Legrande:
 II> If you had a trace of hum origionally, higher capacity values
 II> SHOULD correct it.  One question: Is there hum on your transmitted
 II> signal, (any mode)?
Haven't gotten to that point yet Ivy.  The R-4 is part of the Drake
series-4 seperates and is just the receiver.  I'm not even going to
try and use the T-4 to provide the injection signal to the T-4X
until I get this hum taken care of.
ALL: I just put the R-4 on the bench again, and for about the
     first minute or two after it was turned on there was no
     hum and I was able to hear static (no antenna connected),
     then the static faded and the hum returned.  The filter
     cap can (C90) that's in there is a SANGAMO #658508.
     Does anyone know if this is the OEM component for
     an R-4 with a SN in the 1800 series ?
Note: Seems the problem has JUST turned into an intermittent one.
      The rcvr has been working OK for the last few hours,
      ever since I pulled V6 (6GX6) while the rig was on and
      put it back in.  One of those "now what was it I did?"
      situations.  I'm still going to replace the caps, and
      hoping that a replacement of ALL new tubes will restore
      100% operation.  I'd also like to upgrade the diodes in
      the PS circuit with a half (or full) wave bridge package.
      Although I must say that I was copying a station in North-
      ern Oregon with just a short whip (abt 3' tall) connected
      to the ant jack.
      I -LOVE- these Drakes :)))  Reminds me of the Lafayette
      25-B that worked better after being op'd w/o an antenna
      for a couple days, than it did b4 :)
Next job is to get the HF triband vertical repaired and installed,
and integrate the T-4X with the injector signal from the rcvr.
If anyone can take a look at the array I have diagramed on my
HamPage at http://www.qsl.net/kb6lwn and tell me what make/model
it is I can order the parts needed and re-assemble it. 
Sincerely,
           Bruce - kb6lwn@juno.com - http://www.qsl.net/kb6lwn
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