Tach Signal on an oscilloscope.
#1
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Tach Signal on an oscilloscope.
Hey all,
Been searching with no luck.
I'm wondering if anybody has the basic specs on the signal for the tachometer. Like the frequency (Range?), amplitude, and duty cycle.
Or maybe constant frequency and varying duty cycle?
I don't have an oscilloscope yet, do you?
I'm thinking about a DIY cruise control.
Thanks
Been searching with no luck.
I'm wondering if anybody has the basic specs on the signal for the tachometer. Like the frequency (Range?), amplitude, and duty cycle.
Or maybe constant frequency and varying duty cycle?
I don't have an oscilloscope yet, do you?
I'm thinking about a DIY cruise control.
Thanks
#2
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Everything you could possibly want to know about the tach signal:
https://www.yotatech.com/forums/f116...gniter-287857/
But don't forget: the tach signal will do you no good for a cruise control. You want a signal proportional to over-the-ground speed, not engine speed. So you want to use the VSS1 signal. Which is already well-conditioned. So have at it.
https://www.yotatech.com/forums/f116...gniter-287857/
But don't forget: the tach signal will do you no good for a cruise control. You want a signal proportional to over-the-ground speed, not engine speed. So you want to use the VSS1 signal. Which is already well-conditioned. So have at it.
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That should do it. Thanks.
Engine RPM with a manual transmission represents a scalar ground speed.
Doesn't matter what the scaling factor is (changes with gear, diff ratio & tires)
As long A RPM is constant, speed is constant. (if you don't step on the clutch)
Auto transmission is of course a different story. My speedo is cable driven.
Engine RPM with a manual transmission represents a scalar ground speed.
Doesn't matter what the scaling factor is (changes with gear, diff ratio & tires)
As long A RPM is constant, speed is constant. (if you don't step on the clutch)
Auto transmission is of course a different story. My speedo is cable driven.
Last edited by Runner4Luke; 08-11-2015 at 11:50 PM.
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You still have a VSS1; yours is a reed switch in the combination meter (instrument panel). http://personal.utulsa.edu/~nathan-b.../6combinat.pdf Just so you know.
#6
Hey all,
Been searching with no luck.
I'm wondering if anybody has the basic specs on the signal for the tachometer. Like the frequency (Range?), amplitude, and duty cycle.
Or maybe constant frequency and varying duty cycle?
I don't have an oscilloscope yet, do you?
I'm thinking about a DIY cruise control.
Thanks
Been searching with no luck.
I'm wondering if anybody has the basic specs on the signal for the tachometer. Like the frequency (Range?), amplitude, and duty cycle.
Or maybe constant frequency and varying duty cycle?
I don't have an oscilloscope yet, do you?
I'm thinking about a DIY cruise control.
Thanks
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