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Re: NEON- Building a loading meter
Tom U. wrote:
>
> Steve wrote:
> >Building a home-brew meter though economically practical, is not really
> >practical from the stand point of just how important this tool is. As boon.
> >within the average signguys/gals budget.
>
> Not to get into defending "homebrew," but I sometimes sense an
> anti-homebrew trend here. All parts I'm using to assemble my loading meter
> were acquired from someone who builds them for sale to the trade.
>
> Your points about adding a KV meter sound valid, maybe I should add one to
> my "brew." Thanks for the feedback, Steve.
>
> Tom U.
Building an Ammeter for neon loading is simply a matter of chosing a quality
ammeter element and housing it properly. Quality ammeters of this accuracy
are inexpensive and readily available at surplus shops or mail order. If you
have the time to assemble one you will not have to worry if your "homebrew"
is inferior to the $100 you didn't buy.
A DMM (digital multimeter) that Steve described is great. However you
may see a difference between the "rated" ma, the "analog" meter reading,
and the DMM reading. Chances are, the transformer ratings assume a sinusiodal
waveform. The analog meter will read accurately ONLY for sine waves. Add
some non-linear loading (neon)and you won't have an accurate reading although
it might be the reading that the manufacturer can relate to when discussing
loading. The Fluke will give you a True RMS reading. This is a true integration
of the current over the measurement period. The voltage readings have the
same characteristics.
The point being, are we supposed to use "sine" reading meters or "true RMS"
meters to follow manufacturer's instructions???
Personally, I think the manf should give both specifications using real neon loads.
If you think this is confusing I could try to explain why audio componets for
the home have 100W RMS and the same power amp for the car market will boast 400Watts
and why there is no such thing as RMS power in the first place! But that's another
mail list... eh Tom B.
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