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Unread 05-01-2012, 19:41
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Ether Ether is offline
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Re: Victor 883 problem, please help.

Quote:
Originally Posted by Mark McLeod View Post
A run-of-the-mill digital volt meter connected between signal and ground on the output end of the PWM cable sending a standard Victor spec signal will read:
Neutral = .75v
Forward = 1.0v
Reverse = .5v
I couldn't find a spec anywhere for the period of a "standard Victor spec signal".

Is it 20ms period with 1ms, 1.5ms, and 2ms pulses at 5v for reverse, neutral, and forward? And is this what the OP's Futaba 6XAS is sending?

If so, and assuming that the voltmeter on DC setting responds to the algebraic average of a PWM signal, then one would expect the meter to read (2ms/20ms)*5v = 0.5 volts at full forward.

On the other hand, if the meter on DC setting responds the the RMS of the signal, then one would expect the meter reading to be sqrt(2/20*25)=1.6V





Last edited by Ether : 05-01-2012 at 20:26.