[R-390] Variacs...and line voltage...

[Kenneth G. Gordon]

> rbethman@comcast.net wrote:
>
> As to "Surely no USA sources go as high as 126.5V...???", you are
> obviously mistaken, having NO knowledge what the situation is HERE.
> 
> This has been read and verified with an HP-410C, a Weston AC Panel
> Voltmeter, and a Digital VM.
> 
> It IS a concern for SOME older pieces of equipment.

Ken Gordon affirms: :-)

Measured line voltage here in Moscow, Idaho is 127 VAC, rising 
to 128 at times of low load, and I have seen it, rarely, for short 
periods, pop up as high as 131 VAC. I run my SRR-11/12/13 and  
other receivers on their 130 Volt tap, and my R-389 on a 
bucking transformer.

As I said, building a bucking transformer is so cheap and easy, 
there is no reason not to have one

Oh. BTW, I am an Electronic Instrument Specialist (got the 
fancy meaningless title in lieu of a raise) at the University of 
Idaho's College of Science, and correct line voltage is important 
to maximize the longevity of some of our equipment.

We use bucking transformers where necessary, primarily if 
there are no adjustment taps on the power transformers, or if 
the gear is foreign made, usually Japanese, and requires 100 
VAC. Depending on the load, I use either RS transformers, or 
buy appropriate ones from Fair Radio Sales.

Ken W7EKB