Scott,
Jeff's method is ok but the way I usually do it is the same except I also
hook my dvm in series and put it on the Ma scale. Now you can read directly
on the digital dvm and compare it with the meter scale you are trying to
determine. If you don't have a variable power supply add a 10k or 20K pot
into the circuit to vary the voltage. You can even use a 9 volt battery for
the supply. Just be sure that you don't get either meter directly across the
supply or 9 volt battery. It will zap your meters in an instant.
73
Gary K4FMX
> -----Original Message-----
> From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com] On
> Behalf Of KBØNLY
> Sent: Wednesday, March 04, 2009 8:37 PM
> To: amps@hidden-valley.com; amps@contesting.com
> Subject: Re: [Amps] Panel Meter Article, QST
>
> Ok, that's what I was thinking of doing. I know the article in QST had a
> schematic from the author on how to build a test rig to do it. I'll just
> go
> with your method, easier!
>
> 73,
>
> Scott
>
>
> ----- Original Message -----
> From: "Jeff Carter" <amps@hidden-valley.com>
> To: <amps@contesting.com>
> Sent: Wednesday, March 04, 2009 7:27 PM
> Subject: Re: [Amps] Panel Meter Article, QST
>
>
> Hi again, Scott,
>
> I'm sure everybody has their own method, but here's what I do:
>
> I take a variable power supply and a handful of known-good,
> known-value resistors. Starting with the highest value (say 10K
> Ohms), I hook the meter up in series with the power supply and
> resistor.
>
> Turning the voltage up *slowly*, I try to dead-center the full-deflection
> value.
>
> Then, it's an Ohms Law problem. Say the power supply gives 5VDC at
> full meter deflection, and your resistor was a 10k. 5VDC/10K ohms
> gives 500 microamps, which is your meter's full deflection value.
>
> Good luck!
>
> Jeff/KD4RBG
> http://www.kd4rbg.com
>
> ---- Original message ----
> >Date: Wed, 4 Mar 2009 19:14:59 -0600
> >From: KBØNLY <kb0nly@mchsi.com>
> >Subject: [Amps] Panel Meter Article, QST
> >To: <amps@contesting.com>
> >
> >While not strictly amp related i figured someone on here would know,
> there
> >was an article in QST a while back showing how to determine the full
> scale
> >value of an unknown analog meter, i can't find that searching the members
> >only part of the ARRL website but i know its there somewhere.
> >
> >Anyone know??
> >
> >While working on my recent amp project i unearthed a few unknown meters
> >from my junkbox and i would like to check their function and value.
> >
> >73,
> >
> >Scott KBØNLY
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