Re: DC meters with AC Re: Ignition coil (anti-parallel pairs) array and other questions
This may be getting old but...
My cheap Radio Shack 0-130 volt AC meter is just a 0-1mA dc meter that has
a small bridge rectifier in it and a resistor. The recitifer turns the ac
into dc and the resistor limits the current to 1mA full scale when 130VAC
is on the input.
At 10:58 PM 7/19/99 -0700, you wrote:
>I think the original adivce is a bit overstated, I'll offer my suggestions
>for both meters - a single diode will work, but I agree, a simple bridge
>rectifier (full wave) is best - that is what you find inside analog VOMs.
>for both - I have never seen a filter capacitor, certainly not a few
>microfarads, used with a VOM type meter - if you find you want more damping,
>then a RC circuit will do, but I have only seen this kind of circuit in a VU
>meter, and that's not what you want. So, no capacitor.
>for voltmeter. .. in series with AC side of the rectifier, add a resistor.
>you want to calculate the resistor value so that at the max voltage you wish
>(for full scale on the meter) the current through the resistor equals the