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Old August 22nd 06, 08:34 PM posted to rec.radio.amateur.antenna
Bruce in Alaska Bruce  in Alaska is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 25
Default Testing a thermocouple-type RF Ammeter

In article
,
Al Schapira wrote:

Is is valid to test a thermocouple-type RF Ammeter using low
frequency (say 60 Hz) current? I did so and got quite
reasonable results. Hey, current is current, right?

I have three different thermocouple-type RF Ammeters, with
FS ranges of 1.5, 2.0 and 3.0 RF Amps that I wanted to test.
The 2 Amp meter has an external thermocouple (16 mV DC for 2.0 RF Amps)
and the other two have internal thermocouples.

I hooked them all up in series, and also in series with a
Fluke digital AC Ammeter, fed them from 6.3 VAC through a suitable
dropping resistor. All readings agreed within a few percent at various
currents.

Can I now assume that these meters will also function correctly at RF
(i.e. 3 - 30 MHz)?

Thanks.

-Al, W2ADS


Usually done with a calirated DC supply, but Thermal is Thermal
and mostly those meters aren't any better than 2% anyway.....

Bruce in alaska AL7AQ
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