Peter wondered:
> Does anyone know if Bird thruline meters are linear meters
> (i.e. deflection directly proportional to current) with a non-linear
> scale, or if they are non-linear meters (i.e. deflection proportional
> to a function of current) with a non-linear scale?
Well, the element circuit appears as a simple AM detector;
diode, shunt cap to gnd, with a series R into the micro-
ammeter. Therefore, would not the current be the usual
square-law relation? The meter scale is clearly non-linear;
for example, the top scale to "10" is about 100 degrees of
deflection; going on to "20" is only around another 40 degrees,
or so.
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.
73, Jim, KH7M
--
FAQ on WWW: http://www.contesting.com/FAQ/amps
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
|