RPM Input

MikeStang · Post by **MikeStang** » Wed Feb 06, 2019 12:17 am

Can you use the MSD box output as the RPM input into the MK3 Pro? (Using FREQ1)

Noob question, I searched expecting to find the answer, but did not.

Post by **brentp** » Wed Feb 06, 2019 12:40 am

Hi - what kind of signal does the MSD box output? Is it a clean square wave? If so, you should be able to connect it directly to the RPM input.

If it's a flyback signal from the coil, you may need CoilX:
http://wiki.autosportlabs.com/CoilX

Let us know and we can guide you in the right direction. Thanks!

MikeStang · Post by **MikeStang** » Thu Feb 07, 2019 3:23 pm

Not 100% sure of the signal, it got stupid cold here so I have not got a chance to scope that signal. Was just curious if anyone knew. I will scope it and report back, thanks.

PS14 · Post by **PS14** » Thu Feb 07, 2019 7:15 pm

Most all the MSD box's like a 6AL produce a 12volt square wave signal with a 20% duty cycle for a tach signal. simple answer is, yes.

MikeStang · Post by **MikeStang** » Mon Feb 18, 2019 2:25 am

Yup, for sure 12v square waveform.

Post by **brentp** » Mon Feb 18, 2019 10:20 pm

If it is a clean 12v square wave, then you should be good to go without CoilX.

MikeStang · Post by **MikeStang** » Wed Feb 20, 2019 4:38 pm

brentp wrote:If it is a clean 12v square wave, then you should be good to go without CoilX.

Yup, clean square wave. Took a pic of my scope with my phone, was gonna post, but screen glare makes it hard to see.