Funky Resistances on 15, 19, 20, & 30 [resolved]

C

ceedon

New member
During resistance check I ended up with expected values for most terminals save the following:
15 - 7.5M and rising
19 - 222k
20 - 482k
30 - 482k

After an inspection, my best guess is a short where I tried to get clever on socket A.
I don't see any obvious shorts, so I'm trying to understand if the results I'm getting could be caused by shorting something(s) on that socket.

Full set of images are in a google album:
https :// photos . app .goo .gl /D1Hw4b3wYLYTKj2f9
 

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ceedon said:
During resistance check I ended up with expected values for most terminals save the following:
15 - 7.5M and rising
19 - 222k
20 - 482k
30 - 482k
Click to expand...
I would reread what the * means in the manual for 19, 20, and 30.

Terminal 15 connects back to the output transformer and then through the output transformer back to ground.  What DC resistance readings do you get on terminals 5 and 10 on the output transformer on that side?
 
The primary winding of your OT-5 is open.  I see this happen from time to time when the lead out wire get accidentally cut during a build.  If you look at the base of the solder terminal, the wire coming out of the transformer will be wrapped around it and soldered.  If you look on the side where you're having the problem, that thin copper wire will likely be cut and broken.  It is possible to wrap what's left around a piece of resistor lead and solder them together, then jumper that back over to terminal 10.  If that doesn't work, you'll need to seek out a replacement output transformer from us.
 
You're spot on. The enamel wire was broken but looked intact until I nudged it.
I'll try to bridge it back to the terminal. Thanks a ton!
 
Alright, after bridging that back together, 15 is sitting at 208. Much better! Thanks again for the help!
 
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