FC3S tach signal 5V or 12v input

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11-01-07, 03:33 AM

bcool

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FC3S tach signal 5V or 12v input

I found that the FD tachs are 12v square wave input but i don't know if the FC's are the same or not.

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11-01-07, 05:09 AM

RETed

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Isn't it a (pull to) ground pulse?

-Ted

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11-01-07, 12:49 PM

bcool

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Hrmmmm i may have to "test" this theory and bump it to ground a couple of times.

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11-11-07, 11:59 AM

j9fd3s

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i think ted's right? its been a looooong time. we did have mine working, in the 20b/e11/fc though.

looking at the software, i think it wanted a high duty cycle, 6cylinder. i dont remember messing with the pullups at all

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11-15-07, 12:15 PM

CMonakar

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Does anyone know if a pullup resistor & 12v power source needs to be added to the FD tach input wire or can it simply be connected to a standard PWM channel (with the tach getting 12v from a separate wire)?