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Restoring Philco 38-14
#4

Strange thing about that speaker.
After I removed the transformer to try to use it with a PM speaker to align, the resistance of the FC became about 4.5K.
Then it sat awhile on the table, and the resistance increased to 6.5K.
I made an experiment: I put a 9V battery across the field coil, and then I measured the resistance, which became 4.5K again.
So I put the speaker back together and put it in the radio. It works fine.

Now about the radio.
Once the speaker was in, I powered it on and it hummed and motorboated, quite a bit.
Then I realized the shield for the 38 tube was missing. I have a spare from the sacrificial chassis, so I put it in, and the motorboating stopped, but lots of hum and noise remained.
TRhen I remembered to turn off my bench lighting, and the hum went down quite a bit.

Eventually I was able to receive one station (local), but the reception is very noisy.
I think I need to do two things:

1. Try to align it. As I use my isolation transformer, I think the Philco transformer for their generator (which they recommend) is not needed.
2. Buy a polarized AC plug. I am not comfy with the chassis being across 0.15uF cap[ from the Hot Line.
And I only have the non-pols.

Will continue....

People who do not drink, do not smoke, do not eat red meat will one day feel really stupid lying there and dying from nothing.


Messages In This Thread
Restoring Philco 38-14 - by morzh - 09-09-2024, 06:04 PM
RE: Restoring Philco 38-14 - by morzh - 09-14-2024, 03:49 PM
RE: Restoring Philco 38-14 - by morzh - 09-15-2024, 08:30 PM
RE: Restoring Philco 38-14 - by morzh - 6 hours ago



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