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Thread: Tach output pulse timing

  1. #1

    Default Tach output pulse timing

    I have a distributor tester that does not properly handle a magnetic distributor’s output (it triggers off the leading edge of the reluctor signal, rather than the zero crossing) so I would like to trigger it with the MSD box’s tach output instead.

    I understand from another post from MSD that the tach output is a 12V pulse with 20% duty cycle. What I need to know is which edge (rising or falling) corresponds to the coil firing, and whether there is any delay between coil firing and that edge.

    Alan Watkins

  2. #2


    Hello sir,

    its will be on the rising edge

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