Peter,
Your use of an op amp to buffer the current to the meter current of your
choice will work fine since the meter itself is linear. Just make sure that
the input of the op amp looks like 1400 ohms as the standard meter has that
resistance. The only difference you will observe is the damping of the
meter. Key down readings will be the same as with a "standard" Bird movement.
73, Harry, W3IIT
At 08:39 AM 10/02/2000 +0100, Peter Chadwick wrote:
>
>Jim said:
>
>>So, would appear to be that the deflection is proportional
>>to a function of the current, that is it's square.
>
> >But, I may be looking at this incorrectly, or maybe do
> >not understand the question, hi.
>
>No, Jim, you understand the question fine. I'm not too sure that's the
answer I
>want though!
>
>With Bird replacement meters at $70a pop, I'm hoping that a rescaled
>conventional meter and an op amp to drive it will do, with a copy of the Bird
>scale attached to the meter - I have a '2 holer' pick up line, and want the
>meters to make a pwr/SWR meter to rack mount in the antenna tuner/switch
rack.
>
>73
>
>Peter G3RZP
>
>
>--
>FAQ on WWW: http://www.contesting.com/FAQ/amps
>Submissions: amps@contesting.com
>Administrative requests: amps-REQUEST@contesting.com
>Problems: owner-amps@contesting.com
>
>
>
Microwave Update/Hamarama 2000
September 28, 29, 30/October 1, 2000
PHILADELPHIA, PA.
FOR INFORMATION VISIT
http://www.ij.net/packrats/MUD_2000/mud.html
--
FAQ on WWW: http://www.contesting.com/FAQ/amps
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
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