|
Ok guys, I decided to test voltages and resistance on the 6CD6 tube b/c I was comfortable doing that. This being my first time trying to diagnose a major issue in a set. I have one of the octal test sockets, so could test the voltages from the top of the chassis and very quickly. Set it all up, popped the plate cap off the 6CD6 and fired up the set. No red-plating so proceeded with the testing. Below are the results of the voltage testing:
Pin# / Correct Voltage / Actual Voltage
1 /0 /0
2 /0 /0
3 /0 /0
4 /-23 VDC /-18 VDC
5 /-23 VDC /-18 VDC
6 /310 VDC /222 VDC
7 /6.3 VAC /7 VAC
8 /115 VDC /71 VDC
9 /do not test /did not test
I then tested the resistances as outlined in the SAMS:
Pin # /Correct Resistance /Actual Resistance
1 /Inf. /Inf.
2 /0 /0
3 /0 /0
4 /488K /1 meg
5 /488K /1 meg
6 /50K /55K
7 /.1Ω /Inf.
8 /9K /12K
9 /35Ω /Inf.
Not sure if you guys can look at the schematic and tell anything from these readings, but the biggest things I see amiss are in the resistances. Pins 4, 5, and the plate cap.
I did also test the two doorknob caps and they were both in the 500 PF range. Like 530 pf each. Rated at 500 pf. Also the 1b3 and 1x2 tubes in the HV cage tested fine. Damper and HV osc tube tested fine as well. I also did swap the damper, 6CD6 (HV output), and HV osc tubes and still have same condition.
Let me know if anyone has any suggestions.
Thx.
__________________
-Al
|