[R-390] Question about VARIAC

[Barry]

> It's just an autotransformer with a variable tap.  The variable tap
> sweeps all 292 turns, so if you connect the line across all 292
> turns, the variable output will sweep from 0 V to the line input
> voltage.  This is a very common variac connection, so unless there is
> something very unusual about that particular one (like, the laws of
> electromagnetism don't apply to it), it should work fine.
<snip>
> Best regards,
>
> Don

I guess what I was getting at was impedences.  If I were to tap the input at 
one turn (or two or three), then I assume this would appear as a very low 
impedence and wouldn't work very well (most likely incurring a very heavy 
current draw and hopefully trip the circuit breaker before burning out the 
transformer.  If there were double, triple, etc., the amount of turns, this, 
too, would affect the input impedence, would it not?

I guess what I was trying to say is that I figure there's a point where the 
number of turns matters but just wasn't sure where that point is.  Is that 
incorrect?

Thanks,
Barry - N4BUQ