In message , John Fields
writes
On Thu, 19 Nov 2009 20:21:53 +0100, "Arie de Muynck"
wrote:


"John Fields"
Arie de Muynck...

John Fields ...
Ian Jackson ...
Is that really a 5 microamp meter, or actually just a meter with a 5
microamp FSD scale?
It's real. :-)

And a real beauty it is.

What is the internal resistance,
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Can't find the spec but, measured here, about 6000 ohms.
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AKA how much uWatt does it need?
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Since P = I²R = 5e-6A * 6e3R = 3e-2W = 30mW for full-scale deflection.

Uh?

P = I²R = (5e-6A)^2 * 6e3R = 150 nW full-scale.
How about energy efficient...

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Aarghhh!!!

Right, thanks. :-)

JF

You can probably make the needle move simply by staring hard at it!
--
Ian