[ARC5] Re: [Milsurplus] RF Ammeter Puzzle

[J Forster]

(a) I don't have an ART-13 or even a meter, and (b) the DC won't go through the
current transformer...  you'd have to have a high current RF source.

Robert Downs opined a 20:1 ratio on the transformer ( it's wound on a Steatite
bobbin, not a magnetic core), but I'm no so sure. A 250 ma FS TC RF ammeter would
be very delicate.

The original question was if the referenced meter needed an external shunt and /
or current transformer and, to that end, I was trying to ID it's original
purpose.

Best,
-John



Bruce MacMillan wrote:

> Don't know for sure but that's what the manual says. Being a TC device
> it will work with dc current as well so set up a load with known E/R and
> see what happens.
>
> Bruce
>
> J Forster wrote:
>
> >I don't understand "0-0.25 amperes with a 20X expanded scale".  Do you mean
> >the meter movement is 0.25 A DC and the TC produces .25 A in the meter DC
> >circuit with an RF current of 5 A ?
> >
> >The 1:1 transformer is clearly a current transformer, used to isolate the
> >meter guts from the high RF voltages on the antenna line (as in the BC-442).
> >
> >Best,
> >-John
> >
>
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