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    Building, troubleshooting and testing of these amplifiers should only be
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Counterpoint SA 3000 Transformer

Counterpoint SA 3000 Transformer Help

OK, many thanks.

Here a pictures for the transformer
 

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anatech

Administrator
Paid Member
2004-06-06 8:31 pm
Georgetown, On
Hi susannsusann,
Your transformer should be a dual primary which can be wired for 240 VAC, so you shouldn't need a new transformer. There is another way to go about this. Buy a 240 to 120 V step down transformer and everything will be well.

Two options, neither needs a new power transformer.

-Chris
 

anatech

Administrator
Paid Member
2004-06-06 8:31 pm
Georgetown, On
Hi susann,
I just looked at an SA-3000 and measured the raw DC after the rectifier. It runs at 377 volts with 120 VAC input. The regulated output is 245 volts. The bipolar supplies (raw) deliver 22.5 volts plus and minus and the heater is 13.1 volts (too high I think). I don't have the current draws yet, but the HV looks like 50 mA of actual draw. I haven't measured this, but that is a common HV draw for this brand. You would benefit from making the transformer a little more robust and dropping the heater voltage a little. It's running 6.3 volt heaters from 13.1 volts. That is a lot of wasted energy that also heats the transformer.

I hope that helps you out a little. I will have this preamplifier for a short while, so I may be able to get you more information later.

-Chris