The PHILCO Phorum

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What do you folks recommend for a reasonably priced variac?  What current rating for working on vintage radios?
many thanks
[attachment=24176]Many of these variacs are a variable auto transformer, not isolated from the mains. I’ve been using an RCA Isotap WP-27A for many years. It is not continuously variable but instead, you can vary the out put voltage in 5V steps from 25V to 150V. One big advantage is that in addition to adjustable output voltage it is also an isolation transformer, 2in 1. Works great but sometimes might take awhile to find one!

Ron
+1 for what Ron said.
I use an old Heathkit IT-1 circa 1955.  http://www.w6ze.org/Heathkit/Heathkit_018_IT1.pdf
It does isolate and is adjustable but only down to about 80v and being from the pre polarize
plug era it doesn't like them.

Easily handles any ac/dc set and is rated @ abt 200w with a break every now and then. Most
of the time with AC/DC set I'm just careful to make sure that the neutral side is at b- and couple
signals thru loops, nothing with a chassis connection. Sometimes I'll get a set with a problem
with hum modulation that's where it comes in really handy.
I prefer them separate.
I have a 500VA variac and a Fluke medical isolation xfmr. Yes, more space, but smaller space sometimes dictates lower power.
I also have one boost variac that allows to get 300V from 120V.
I use what Ron has, a variac and isotap. Best of both worlds.
I believe the Isotap WP-27A is good for 400 watts which will handle any radio you work on and even old tube TV sets. It is just one unit on your bench and doesn’t  take up much space!

Ron