Hi Peter,
I saw somewhere that the meter resistance is supposed to be 1400 ohms. The
ones I have measure 1399, 1406 and 1393 ohms.
The 1399 ohm meter reads about 10% low with 30 microamps thru it.
The 1406 ohm meter reads about 5% low with 30 micromaps thru it.
The other meter is way out in left field.
In one meter that I opened up it had a 200 ohm resistor in series with the
movement.
73
Gary K4FMX
> -----Original Message-----
> From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com] On
> Behalf Of Peter Chadwick
> Sent: Monday, May 07, 2007 6:12 AM
> To: amps@contesting.com
> Subject: Re: [Amps] Bird wattmeter
>
> Gary
> have you checked the total meter resistance? In mine, it's surprisingly
> high - around 1350 ohms. Depending what sort of resistor they use in the
> meter, that could have drifted.
> 73
> Peter G3RZP
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