05-19-2020, 10:25 PM
After replacing the speaker socket again (seemed like in had an internal short). The hv came up for a few seconds and died. Problem is hv feed off of the field coil was showing a short of 2.3 ohm to ground.
The way the power supply is designed the hv is split into two parts. One side comes off the rectifier tube and into the filter choke. In turn that leg powers the output stage. The other the choke is connected to the field coil and field coil leg feeds all of the low level circuits. The leg off of the choke was at 265 or so.
Did find a couple of possibles in that giggling the wiring cause it to be intermittent. Started disconnecting wires to see if I could find it and guess where I ended up??? 2nd IF transformer[Image: https://philcoradio.com/phorum/images/sm...wisted.gif]. It came back to bite me! I didn't replace it back when it smoked the resistor. The resistor was fine this go around but it had a good shadow meter coil in parallel with it. Tomorrow I'll be pulling pigtales on the replacement ift and installing it.
The way the power supply is designed the hv is split into two parts. One side comes off the rectifier tube and into the filter choke. In turn that leg powers the output stage. The other the choke is connected to the field coil and field coil leg feeds all of the low level circuits. The leg off of the choke was at 265 or so.
Did find a couple of possibles in that giggling the wiring cause it to be intermittent. Started disconnecting wires to see if I could find it and guess where I ended up??? 2nd IF transformer[Image: https://philcoradio.com/phorum/images/sm...wisted.gif]. It came back to bite me! I didn't replace it back when it smoked the resistor. The resistor was fine this go around but it had a good shadow meter coil in parallel with it. Tomorrow I'll be pulling pigtales on the replacement ift and installing it.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!
Terry