RPM Input

General Q&A specific to RaceCapture/Pro. For app related questions post in the RaceCapture App forum. also see the <a href="http://www.autosportlabs.net/RaceCapture">RaceCapture Information Page</a>

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MikeStang
Posts: 10
Joined: Thu Jan 24, 2019 8:31 pm
Location: Firestone, CO

RPM Input

Post by MikeStang »

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.
1981 Mustang track car

brentp
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Post by brentp »

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!
Brent Picasso
CEO and Founder, Autosport Labs
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MikeStang
Posts: 10
Joined: Thu Jan 24, 2019 8:31 pm
Location: Firestone, CO

Post by MikeStang »

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.
1981 Mustang track car

PS14
Posts: 97
Joined: Fri Feb 12, 2016 11:27 pm
Location: NY

Post by PS14 »

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
Posts: 10
Joined: Thu Jan 24, 2019 8:31 pm
Location: Firestone, CO

Post by MikeStang »

Yup, for sure 12v square waveform.
1981 Mustang track car

brentp
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Post by brentp »

If it is a clean 12v square wave, then you should be good to go without CoilX.
Brent Picasso
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MikeStang
Posts: 10
Joined: Thu Jan 24, 2019 8:31 pm
Location: Firestone, CO

Post by MikeStang »

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.
1981 Mustang track car

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