Re: Resistance of ammeter caused voltage drop

From: Fred Bloggs (nospam_at_nospam.com)
Date: 03/16/05 

Date: Wed, 16 Mar 2005 02:16:09 GMT

Larry Brasfield wrote:

>
> Measure the current with ammeter in at the ordinary
> supply voltage. Call this Iao. Measure the voltage
> at the transmitter with same lashup. Call this Vao.
> Measure the drop across the ammeter, Vad.
>
> Reduce the supply voltage by an amount similar
> to what the ammeter drops, leaving the ammeter
> in place. Measure current and voltage, to be
> called Iar and Var respectively.
>
> Calculate Rt = (Vao - Var) / (Iao - Iar)
> This is the slope of the voltage versus current
> characteristic for the transmitter.
>
> Calculate Ina = Iao + Rt * Vad
> This is an approximation of the current the
> transmitter draws when you have no ammeter
> to reduce the supply voltage it sees.

Yeah? So the F___ what? And since when is resistance x voltage equal a
current?- and you don't even have the sign right. Here's the deal you
worthless, pretentious son-of-a-bitch-with-VD, you are a worthless
p.o.s.- we are wise to your dumb ass- go away.

> You could also put a lower shunt resistor across
> your ammeter and calibrate the combination.
>

Or buy/modify a p.s. with external sense compensation, damned worthless
idiot.

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