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Rehabing 42-854 AM/SW Portable
#32

UPDATE!!!!!!!!!!!!!!!!!
I found the problem with a IF stages it was two fold. I took a dum***s pill before recapping and connected the 1/2 mic cap from the plate of the IF amp to B-. This pretty much shorted all of the IF signal to ground.  To confuse thing a bit it looked like there was a jumper ( I think this was a nub from when I removed the old cap) from the plate pin to the next pin which is a NC inside the tube (used as a terminal post) The jumper was a red herring it was where the .5 cap should have been connected. So got that sorted out.

Now the other part of the problem I could get a signal from the grid of the 2nd IF amp but nothing from the 1st IF or Mixer plate. It was suffering from the same problem as my old HRO, the IF transformers where way out of alignment. Set the generator at 455KC and peaked up the three IF cans. The IF on this set is pretty hot when it's all aligned up.

I had some fears that the LO wasn't working as I couldn't hear it in my little transistor set. But once the IF was working I twisted the tuning knob and hear a number of BC stations, this is without a loop connected or ant.

I did use a isolation transformer when servicing to get rid of the AC modulation.

Still need to double check the SW band to see if it is working properly and lube the tuning. It's well on it's way to recovery.

So Mike that 25W resistor still gets pretty hot. Probably about as hot as the 117Z6. 5.5wts would burst into flames!!!

Terry


Messages In This Thread
Rehabing 42-854 AM/SW Portable - by Radioroslyn - 05-22-2016, 02:08 PM
RE: Rehabing 42-854 - by morzh - 05-22-2016, 02:29 PM
RE: Rehabing 42-854 AM/SW Portable - by sam - 05-23-2016, 02:33 PM
RE: Rehabing 42-854 AM/SW Portable - by morzh - 05-23-2016, 04:40 PM
RE: Rehabing 42-854 AM/SW Portable - by sam - 05-26-2016, 06:55 PM
RE: Rehabing 42-854 AM/SW Portable - by morzh - 05-26-2016, 08:06 PM
RE: Rehabing 42-854 AM/SW Portable - by morzh - 05-26-2016, 08:45 PM
RE: Rehabing 42-854 AM/SW Portable - by morzh - 05-27-2016, 08:06 AM
RE: Rehabing 42-854 AM/SW Portable - by morzh - 05-27-2016, 11:11 AM
RE: Rehabing 42-854 AM/SW Portable - by sam - 05-27-2016, 11:31 AM
RE: Rehabing 42-854 AM/SW Portable - by morzh - 05-27-2016, 06:44 PM
RE: Rehabing 42-854 AM/SW Portable - by sam - 05-27-2016, 08:21 PM
RE: Rehabing 42-854 AM/SW Portable - by morzh - 05-27-2016, 08:44 PM
RE: Rehabing 42-854 AM/SW Portable - by sam - 05-30-2016, 07:07 PM
RE: Rehabing 42-854 AM/SW Portable - by morzh - 05-31-2016, 07:22 PM
RE: Rehabing 42-854 AM/SW Portable - by morzh - 06-01-2016, 08:04 AM
RE: Rehabing 42-854 AM/SW Portable - by Radioroslyn - 06-02-2016, 11:19 AM
RE: Rehabing 42-854 AM/SW Portable - by morzh - 06-02-2016, 01:19 PM
RE: Rehabing 42-854 AM/SW Portable - by sam - 06-02-2016, 12:05 PM
RE: Rehabing 42-854 AM/SW Portable - by morzh - 06-02-2016, 07:52 PM
RE: Rehabing 42-854 AM/SW Portable - by morzh - 06-02-2016, 09:20 PM
RE: Rehabing 42-854 AM/SW Portable - by morzh - 06-02-2016, 09:58 PM
RE: Rehabing 42-854 AM/SW Portable - by morzh - 06-04-2016, 02:09 PM
RE: Rehabing 42-854 AM/SW Portable - by morzh - 06-04-2016, 04:18 PM
RE: Rehabing 42-854 AM/SW Portable - by sam - 06-16-2016, 10:13 PM
RE: Rehabing 42-854 AM/SW Portable - by morzh - 06-17-2016, 10:32 AM



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