[Collins] KWM-2A 2 repairs & difficulties (longish)

[Al Parker]

Hi Folks,
	I lived with an AVC problem in my KWM-2A for several weeks, the RF gain 
ctrl had minimal affect on the AVC, and the rcvr's controlled stages 
were running wide open, it seemed.
	Then last Sun. I was told, on the Vintage SB Net, that my audio had 
become terrible.  It became time to open it up and fix things.
	The AVC trouble was R-133, a dropping resistor from the -70v line to 
the RF gain ctrl.  The big problem there was finding it physically. 
Thanks to DW Holtman's great CD, I was able to find it back near the 
relays.  Without that I have no idea how long it would have taken to 
find it.  Thanks DW and everyone who supplied him with info.  It 
measures 50k vs 18k expected.  I pulled the audio output xfmr loose to 
gain access.  That one fixed, I hope.
	Next, the crappy audio.  First suspect would be a cathode bypass in an 
mic amp stage, and there it was, C259, 8uf, at the 2nd mic. amp.  It's 
ESR is off scale high, so probably is the problem.
	Here's the question -- how do you wizards that work on KWM-2's 
regularly replace that capacitor??  You can barely see it, it's buried 
so well, and I had to work to get a probe down to the cathode pin on the 
tube socket to measure the ESR.  It'll take a very skinny soldering tip 
to get in there to solder another lead on, and I can hardly imagine even 
clipping the old one out, much less de-soldering it.
	I'm open to suggestions - please help ;-)
	The Hakko desoldering unit is a great help, did the job for the AVC 
res., but I don't think it'll fit down to the socket pin for the cap.
tnx, 73,

Al, W8UT
www.boatanchors.org
www.hammarlund.info

"There is nothing -- absolutely nothing -- half so much
worth doing as simply messing about in boats"
Ratty, to Mole