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SB220 transformer, alternatives

Cable Guy

Growth must be chosen again and again.
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Dec 29, 2010
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I'm looking for a hv plate transformer. Specs: 1 amp, 220/240, 1800-2200 secondary. It's for a friend and those are the specs he quoted. An original Heath Kit would be okay, but anything that can feasibility be retrofitted is an option. I understand they are rare.
 

1800-2200 secondary
Only if he plans to use a full-wave bridge rectifier. That model is built with a full-wave voltage doubler circuit. Calls for a transformer secondary voltage half what you specified.

The Peter Dahl-designed parts are pretty much the only game in town. Most any substitute will have to go into an external box. Won't fit in the original space. The -3 version above is a bit too tall for the original shield cover. Uses a different core design. Requires cutting a notch in that corner over the HV transformer.

Never could figure out why the transformer for a Heath SB-1000 one-tube Z box is physically larger than the SB220 HV transformer. The failure of a factory-original SB220/221 HV transformer seems to be a matter of when, not if.

73
 
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Thanks Nomad, I will pass that info on. I don't know what he plans to do with it, or if it's even going into a SB220, I just assumed. The Peter Dahl transformer is 860-1171 volts, and I guess he knows that. Maybe not. He said an original would be fine, and I'm guessing it doesn't go over 1200 volts so I don't know where he got the 1800-2200 volt figure unless he is dreaming. It could be a project box he's building, I remember being asked about a transformer about a year ago.
 
I asked what amp it's going in, and he said

Screenshot_20250601-062420.png

He might have a plan, but I don't know and I could ask but I really don't care. My part is done.
 

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