700 Volt XFR??

Express, Liverpool, Rocket, Dirty Little Monster, etc.

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don280z
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700 Volt XFR??

Post by don280z »

OK....I'm gonna build another Express. The only PT I have right now is a 350-0-350 volt. Will this work?.....or should I order a 300-0-300 volt??
I will be running EL34's....
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selloutrr
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Re: 700 Volt XFR??

Post by selloutrr »

It should be fine you may want to dumb down some of the voltage depending on the transformer being spec'd for 117V or current 120V
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don280z
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Re: 700 Volt XFR??

Post by don280z »

The XFR has a 120volt primary, and voltage around here runs a strong 120 (more like 123 volts). Could I could build in a voltage divider circuit to drop the 350 voltage down to 300 volts? Any ideas??
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RJ Guitars
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Re: 700 Volt XFR??

Post by RJ Guitars »

I think you're on the right track looking for 300 volts and you can get there with a very big zener diode... but there is more to the story than just the voltage. Trainwrecks tend to use oversized iron and some of the amp complexity involves the interaction of the power handing characteristics of the power tranny.

That voltage is not far from a Komet spec and is popular with the HiFi crowd. You might look at selling or trading it and use the funds toward Wreck spec tranny if you want to go down the path of least resistance. (I mean that in many ways).

If you make it work with some technical wizardry I hope you'll share that with us so we can all learn something.

rj
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passfan
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Re: 700 Volt XFR??

Post by passfan »

I have run a few rockets and an express at higher voltages with no ill effect. If you're shooting for accuracy then check out to the proper size.
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