Does anyone know if this circuit will work to drive field coil speakers.Which need a variable vdc of 0-120.

Not sure but I think the design already has a patent

Not if you value safety.

Why whats wrong with it,do you know of a safe way.Would really like some help.

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It doesn’t have a mains isolating transformer, just the autoformer to vary the voltage. At minimum it needs a mains transform after autoformer.

Frankly, it’s a very primitive supply and will have a lot of ripple as it doesn’t have much capacitance.

Plus, if you have to ask, then you clearly don’t know enough about electronics to be messing with hazardous voltages.


Your right of course.I have been looking for some one to make me one but not having much luck at the moment.

Just buy one like this:

ÂŁ350, lol.

I couldn’t find a cheaper one that did up to 120V, although I didn’t look very hard. I was working on the principle that it would be cheaper than killing himself!

Where are the thread merge people when you need them ?


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