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Old August 19th 06, 08:56 PM posted to rec.radio.amateur.homebrew
John, N9JG John, N9JG is offline
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First recorded activity by RadioBanter: Aug 2006
Posts: 83
Default Can I use a 120V Variac to get 220V?

Your advice is elegant in its simplicity.

"Andrew VK3BFA" wrote in message
oups.com...

wrote:
I want to reform the electrolytics in an amp I'm bringing back to life.
It runs high power, 220 volts ac only.

Can I use my 110 volt variac in conjunction with a 110V to 220V step-up
transformer to power up the amp? Obviously I'd not go key-down, but I
do want to ultimately get to the full B+ on the tubes.

How would I wire-up the variac / transformer, assuming it's possible?

Thanks in advance for the help, guys.

73,
Jeff
W8KZW


Its relatively simple and easy. Connect a 100w light globe in series
with the ac power input - this will limit current to a safe level. Run
for 10 hrs or so, will give caps a chance to reform....start with the
tubes in so the filament current draw limits cap voltage, then later
remove tubes to get virtually full voltage across caps....

Andrew VK3BFA.