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Parmak rebuild (Parker McCrory)
#2

More observations and pictures: It appears that this has had quite a bit of repair work done in the past, even up to a full recap. Most of the caps I removed were Spragues. I also suspect the tuning eye tube may have been added, since it uses a 6E5, rather than the older 6U5. Could have been modded to accept the newer tube, but I can't tell for sure. It does look like it was fairly decent repair work previously. 

I do have a few issues and questions. It only had one electrolytic cap coming off the cathode of the 80. No others. The neg from the original can is not grounded and has (I believe) a negative voltage to chassis ground. The old replacement had the negative going to a tap on the bias candohm resistor instead of across the original. I connected the new cap across the original (of course, removing the old cap from the circuit). It had a little hum, so I tried it the way the replacement was in. It made the hum a lot worse, so I returned it to the original position. I suspect the hum may be due to not using the hum bucking coil on the original speaker. 

I also noted the power transformer had been replaced. The eye tube brightness will flicker when the volume is turned up, to the tune of whatever is being played. When it is turned down, it is normal. The B+ jumps around when the volume is up. May be the wrong output trans? Or, the wrong power trans? I tried adding another electrolytic in parallel. No change. I am using a 10mf cap (original was 12, and the old replacement was 16). 

So, I am hunting an output trans. Found a maybe from Hammond. Any suggestions or ideas from what I have shared so far?

Below is a close up of the power supply area. You can see the stub of the replacement e-cap wire from a previous repair on the candohm. 2nd lug from the top. I left that to remember where it had been in case I needed to move the new cap neg to that point.
   
Overall recap
   

If I could find the place called "Somewhere", I could find "Anything" Icon_confused

Tim

Jesus cried out and said, "Whoever believes in me , believes not in me but in him who sent me" John 12:44


Messages In This Thread
Parmak rebuild (Parker McCrory) - by TV MAN - 01-29-2018, 04:34 PM
RE: Parmak rebuild (Parker McCrory) - by TV MAN - 01-29-2018, 04:53 PM
RE: Parmak rebuild (Parker McCrory) - by TV MAN - 01-29-2018, 06:26 PM
RE: Parmak rebuild (Parker McCrory) - by Arran - 01-30-2018, 05:56 AM
RE: Parmak rebuild (Parker McCrory) - by TV MAN - 01-30-2018, 11:34 AM
RE: Parmak rebuild (Parker McCrory) - by Arran - 01-31-2018, 01:14 AM
RE: Parmak rebuild (Parker McCrory) - by Arran - 02-01-2018, 02:36 AM



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