X100 apparently fails dim bulb test (DBT)

[rufleruf]

I pulled the end bells off the transformer last night and everything looks good at first flush - no burned or otherwise suspect wires. I did some continuity readings and I have open circuit between all the red / red-yellow leads to matter how I test, so I guess that's the problem.

I bought a PT off BT that is the same ratings as the Triad pictured above - hopefully it does the job!

 

[fred soop]

Interesting and strange that both halves of a center tapped winding would be open. One possibility is that the connection of the internal wires from the windings that are joined at the center tap has gone bad. Nothing to lose by opening the transformer, peeling back the insulation, and attempting to observe the connection.

 

[gadget73]

If that was open, it wouldn't explain why it fails a dim bulb test. Open windings will pass that, shorted turns are what cause the current draw.

 

[rufleruf]

I haven't exhaustively cross checked the wires - there may be a short between some of the other leads. I plan on digging into it some night this week to see what else I can find.

I've successfully fixed a lot of tube Fishers and this one has me doubting myself.

I may push it to the back of the line for a while. I just got a really nice 400 in a trade that needs the electrolytics replaced at the least - thread on this soon.

 

[gadget73]

well its not to say that the HV winding didn't short itself internally as well as losing connection. Dead is dead really.