Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: joesatch on October 11, 2021, 03:24:45 pm

Title: Variac
Post by: joesatch 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?

Title: Re: Variac
Post by: mresistor on October 11, 2021, 04:11:05 pm

https://www.circuitspecialists.com/variac-with-digital-display-tdgc2-2d.html (https://www.circuitspecialists.com/variac-with-digital-display-tdgc2-2d.html)
there are probably cheaper options 

Title: Re: Variac
Post by: mresistor on October 11, 2021, 04:13:27 pm

post up the link to the amazon variac  so we can see it

Title: Re: Variac
Post by: sluckey on October 11, 2021, 04:25:50 pm

https://www.amazon.com/Variable-Transformer-Voltage-Regulator-Converter/dp/B07BWD2Q4Q/

Title: Re: Variac
Post by: acheld on October 11, 2021, 08:23:48 pm

eBay has them for cheaper.  Looks like the same product.  Shipped from friendly Chino CA!

https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2334524.m570.l1313&_nkw=variac+10+amp&_sacat=92074&LH_TitleDesc=0&_odkw=variac+10+amp&_osacat=92074&LH_PrefLoc=3

Title: Re: Variac
Post by: PRR 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/

Title: Re: Variac
Post by: 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
(https://images.squarespace-cdn.com/content/v1/56fbe87462cd94ff6ec9d02c/1459446960268-PP4ODTQP30YZE1CHLB24/1.JPG?format=2500w)

Title: Re: Variac
Post by: mresistor on October 12, 2021, 06:31:45 pm

Mine is a Staco  but no digital meter..   

Title: Re: Variac
Post by: sluckey 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