Output Transformer

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Paul Smith
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Output Transformer

Post by Paul Smith »

Hello, I had a question regarding a Fender Output Transformer: Codes 022889 and 606930, Im not sure if that would be 30th week of 1969 or 1979? I measure resistance in the primary from the Center Tap Red, to blue, which measured 35 ohms, and Center tap Red, to Bronws which also measured 35 ohms, however measuring from Brown To Blue, does not show an ohms reading, just O.L on my DMM. Is this ok? The Blue and Brown wires of the primary are the wires that connect to the plates of the Output Tubes. The Secondary wires which connect to the speaker output, measures at .5 ohms. I think all this is ok, but perhaps an expert could chime in?

thanks very much,

Paul Smitty Smith
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Bill A. Moore
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Post by Bill A. Moore »

What scale is your meter set for?
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Paul Smith
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Post by Paul Smith »

Its a flike 87 DMM set to ohms resistance, i do not think you can set the scale
Donny Hinson
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Post by Donny Hinson »

First off, that’s a 1969 transformer. Second, what you describe with the ohms readings cannot happen unless there’s an intermittent connection somewhere. Could be in the meter leads, or in the transformer leads. Try again with the meter leads firmly fastened to the transformer leads. Then wiggle to see if the readings change.

If a=16, and b=16, then a+b has to equal 32. :!:
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Bill A. Moore
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Post by Bill A. Moore »

An 87 is auto ranging, unless the "range" button is pressed, (sometimes inadvertently), don't ask me how I know!
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Dave Grafe
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Post by Dave Grafe »

What Donny said
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Paul Smith
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Post by Paul Smith »

Thanks very much for your input, I cut off/stripped some insulation off of the ends of the Blue, and Brown wires, and I can now get a reading between the 2 wires.

thanks for all your help!

Smitty
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