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City: Lompoc CA
Transformer readings:
primary 11 Ohms
secondary: 290Vac 488K Ohms
secondary 6.3Vac 1 Ohm
transformer looks a lil like it burnt
secondary 290 Vac seems high
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City: Jackson, NJ
The xformer is shot, copper winding is neve in hundreds of kOhms. The only reason you are actually seeing some finite resistance is that you either hold it with your both hands, or you are measuring charred paper.
Either start rewinding or get a new one.
(This post was last modified: 05-19-2012, 03:55 PM by
morzh.)
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What does it read from each leg of the high voltage winding to the center tap? The resistances should be close to equal, or voltages if you are applying power to the transformer. From what I know of the way brand Z did things the transformer was likely marginal to begin with, any overload would cause a smoke show even if the set was using a 5Y4 or an 80 instead of a 6X5. As Morz said the high voltage winding should measure in the 100s of Ohms not thousands, so the meter should be set on the 1000 Ohm range, if you don't get a reading then the winding is barbecued. If it's shot get a larger power transformer as a replacement if it will fit. Stupid brand Z sets!
Regards
Arran
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The voltages on yor dwg - are those measured ot you copied them from the sch? You can't possibly have 290V from a blown winding.
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i have not applied any voltage to the transformer. I'm checking my meters making sure they are ok.
I will check from the center tap to the windings. There was a wax like material all over the bottom of the transformer. About 3/16 thick.
I used the diagram with the tubes on it and a tube book to put the info on the schematics.
Posts: 15,704
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City: Jackson, NJ
well, if you measured indeed 488K, you can stop wasting your time and start looking for a new one.