[R-390] fixer-upper

[Scott Bauer]

 I decided to buy an old fixer upper to try and learn a little
by repairing it myself. I have a couple of manuals and know
how to solder and can follow a schematic just OK.

 Well, this is a little more of a hacked up, torn apart junker
than I thought. Guess where I found it :-)

 I first discovered somebody had unsoldered a couple of the
mechanical filters then stopped whatever they were doing for
some reason. I ohmed them out and then resoldered them, then
installed the IF into a working R390A. GREAT, the IF works!
I then installed a grounded power cord and installed a spare
PTO. This radio did not have one when it arrived. I know that I
am going to be off here but this is just for educational purposes.

 I then checked every tube. All were bad, most missing. Replaced them all
with good used ones. After checking under all of the other modules
for smoke leaks, I checked all of the fuses and moved the function
switch to standby for a few seconds and did not hear the antenna relay.
Then moved it over to AGC. Silence.... Nothing. Darn! I noticed the
OA2 was not burning so I shut it off. The fuse was blown. Geeze,
What have I gotten into. After taking a closer look at the AF module,
I noticed both caps were 45uf. I borrowed 2 known good caps from
another radio and looked around a little more. Ahh... A cut wire
in the harness. I don't know one was able to cut it without damaging
any others, fixed it. I then noticed the RF gain pot had wires falling from 
it.
After re-doing the whole pot, I installed another 1/4 amp fuse and
tried again. The antenna relay clicked in. Great so far!
 Ahh, the OA2 is lit, and I am getting hiss in the speaker!!
 No signals though, just hiss. No signal on any band. .
No difference in noise when I pull the antenna off except for one thing.
 At around 140kc I hear a tone with the bfo on. I still have it on AGC
so I move the switch to calibrate. The tone remains constant whether
the switch is on AGC, MGC or Calibrate. Is the radio somehow
stuck in the calibrate mode?
 I am now stuck. Any ideas? I have no test equiptment besides a volt
meter.

 Regards 



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