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Hoffman Amps Forum image Author Topic: Variac  (Read 3310 times)

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Offline joesatch

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Variac
« on: October 11, 2021, 03:24:45 pm »
Can someone post an decent (and cheap) Variac for amp building/testing? Amazon has a $50 one but it only goes to 500 watts which i assume isnt enough?
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Offline mresistor

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Re: Variac
« Reply #1 on: October 11, 2021, 04:11:05 pm »
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Offline mresistor

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Re: Variac
« Reply #2 on: October 11, 2021, 04:13:27 pm »
post up the link to the amazon variac  so we can see it
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Offline sluckey

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Re: Variac
« Reply #3 on: October 11, 2021, 04:25:50 pm »
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A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!

Offline acheld

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Re: Variac
« Reply #4 on: October 11, 2021, 08:23:48 pm »
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Offline PRR

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Re: Variac
« Reply #5 on: October 11, 2021, 08:59:26 pm »
> it only goes to 500 watts which i assume isnt enough?

What kinda beasts are you working on?

A 300 Watt output SVT may suck 700W at FULL roar. (and you don't want to be on a variac at full power.)

The usual 50W 'big' amps may suck 150W from the wall/variac?

On a good variac the rating will cover a full work-shift, 8+ hours. In amp testing we are usually working it at part-power for a few minutes.

https://www.amazon.com/dp/B078Z7XYT2/
« Last Edit: October 11, 2021, 09:02:25 pm by PRR »
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Offline p2pAmps

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Re: Variac
« Reply #6 on: October 12, 2021, 02:18:14 pm »
Find a clean Staco 3PN1010 and add a meter like this one I did.  You might have 100 bucks in it and you will have yourself a quality tool IMHO.

Cheers
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Offline mresistor

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Re: Variac
« Reply #7 on: October 12, 2021, 06:31:45 pm »
Mine is a Staco  but no digital meter..   
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Offline sluckey

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Re: Variac
« Reply #8 on: October 12, 2021, 06:47:14 pm »
Quote from: p2pAmps on October 12, 2021, 02:18:14 pm
Find a clean Staco 3PN1010 and add a meter like this one I did.  You might have 100 bucks in it and you will have yourself a quality tool IMHO.

Cheers

May be time to upgrade that Staco...  :icon_biggrin:

     https://el34world.com/Forum/index.php?topic=25028.0
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A schematic, layout, and hi-rez pics are very useful for troubleshooting your amp. Don't wait to be asked. JUST DO IT!
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