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Old 10-30-2019, 10:14 AM
Kevin Kuehn's Avatar
Kevin Kuehn Kevin Kuehn is offline
Workin' Late Again
 
Join Date: Jan 2011
Location: WI
Posts: 3,976
Quote:
Originally Posted by Electronic M View Post
If you pull the vertical output tube too and it still draws close to rated power (as I suspect it will) you still need to finish troubleshooting the power supply...Like I said the social coil circuit could be an issue...also depending on where that 390 ohm resistor is in circuit whatever is causing it to smoke is also a likely cause of the overload.
social coil circuit?

R62(390 ohm) is the plate load resistor for the 6V6 audio out(Sams calls it a filter). It supplies voltage from the wiper of the focus coil to the 6V6 plate circuit. This set uses the audio output stage as a voltage dropper, similar to Admiral sets of the time. It's plate voltage(pin 3) should be 205vdc referenced from the cathode(pin 8). Confusing as all get-out to troubleshoot. As mentioned above, best to follow Sams voltage measurement chart to isolate the problem area.

Last edited by Kevin Kuehn; 10-30-2019 at 10:22 AM.
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