Peter:
The elements most of us use require a 30 microamp meter. We have connected
them to an amplifier and a-to-d using resistors to present this load.
They mark the meter face to achieve the translation (you'll notice wide
"spaces" between watts at the low end and compressed "spaces" at the high
end of the scale.) You should be fine if you can find a meter with similar
characteristics to the Bird meter (30 uA FS), or build an amplifier
interface and then you can use any old meter. If you'd like the circuit we
use, contact me off the reflector and I'll send it.
73
Bruce R. Knox W8GN
RF Applications, Inc.
-----Original Message-----
From: Peter Chadwick [SMTP:Peter_Chadwick@mitel.com]
Sent: Monday, October 02, 2000 3:39
To: 'amps'; 'Jim Reid'
Subject: RE: [AMPS] Bird meters
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
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