[HomeBrew] high voltage transformers

[frank]

Yes, I have tried using old microwave oven hv transformers.

My recommendation is, don't use them.

These transformers use shunts to control power output.  The shunts are
sections of iron that are embedded next to the windings.  The shunts
need to be driven out to make the transformer usable in your
application.  I have found it difficult to remove the shunts without
damaging the secondary windings.

Also, these transformers have one side of the hv secondary connected to
the frame.  That is fine for the halfwave rectifier system used in the
ovens, but not suitable for a full wave high voltage supply for an
amplifier.  The HV secondary is not centertapped and a bridge
configuration would have to be used to get full wave rectification.

I would classify these devices in the 'widow-maker' catagory.  The risks
are not worth the savings.

You would be better off trying to connect the secondaries of two lower
voltage transformers in series and/or using a full wave voltage doubler
circuit.

Regards,
Frank Kamp




Durwydd MacTara wrote:
> 
> ** HOMEBREW REFLECTOR - Please do NOT cross-post messages to multiple mailing lists on the "To:" or "CC:" line of the e-mail message. **
> 
> I have been considering using old microwave oven hv transformers for a
> 4cx-250 Amp. Has anyone tried this?
> 
> Dedicated to the art of "sratch building" from the junkbox,
> Durwydd MacTara
> 
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