Michael Tope wrote:
> or do I need a series of several diodes to avoid shunting significant
> meter current thru the forward biased diode?
Michael all silicon diodes need .7 volts before they conduct current.
Germanium .3 volts. The coil resistance for most meters is typically very
low. I have never seen a schematic including diode protection circuitry
that calls for more than one diode in either direction. If your the
exacting type and want peace of mind find out what the coil resistance of
the meter that you are using. Multiply that by the full scale current. That
will yield the maximum voltage across the meter terminals. Take that number
and divide it by .65 . Ignore the decimal value of the quotient and add
one. This is the number of diodes that you will need.
73s
Bob
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