Ampeg SVT3 pro PT problem

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grtamp
Posts: 348
Joined: Tue Mar 23, 2010 9:37 pm

Ampeg SVT3 pro PT problem

Post by grtamp »

Hello everyone,

a friend of mine brought me a Ampeg SVT 3 PRO, telling me when He turn on , the fuse blows.
In fact, the fuse blows even with the secondaries disconnected. could be the transformer fault?

Thanks
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martin manning
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Re: Ampeg SVT3 pro PT problem

Post by martin manning »

That's a definite possibility. See if you have any continuity to ground from any of the windings. If not then you can try this test: http://www.premierguitar.com/articles/t ... r-tester-1
grtamp
Posts: 348
Joined: Tue Mar 23, 2010 9:37 pm

Re: Ampeg SVT3 pro PT problem

Post by grtamp »

Hi Martin , I haven't a neon bulb to do that test !

I have tested the trafo out the amp with a fuse connected to the prim (sec. open). the fuse blows again!

Also I tested the 2 primaries: between black-white 38.11uH 0.544Ohm
between brown violet 19,92uH 0.205Ohm

I tested also between black and violet (White/brown open)and I have measured 0,203Ohm , this makes me think to a internal short!
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xtian
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Re: Ampeg SVT3 pro PT problem

Post by xtian »

grtamp wrote:I tested also between black and violet (White/brown open)and I have measured 0,203Ohm , this makes me think to a internal short!
Yup. Toast.
I build and repair tube amps. http://amps.monkeymatic.com
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