basic question

Feb 13, 2007 3 Replies
M

the speed sendor/sensor on my streetrod transmission turns on and off (pulses) 12v sending it to the speedometer.



I have an old scope that I barely know how to use .. and it shows a nice square wave



with the speedo disconnected my fluke reads 6v so I guess I am measuring average voltage.



now the problem



Im working on a project where I feed these pulses to a microprocessor



If I dont have the speedo connected and just connect the sender to the micro .. it works fine.



but ..



when I connect the speedo and "tap" into the signal line I only measure 1v and its not enough to trigger the micro



not sure what to do ..



thanks for any help mike


Vote
Twitter Facebook LinkedIn
B

CMOS buffer would be easier and better for square waves. The ever-popular CD4049 has 6 in one package. These are inverting buffers, so if polarity is important (which I doubt here), use one of them to invert the sensor signal, and feed it to the rest, which invert it back. You'll then have 5 copies of the signal to use. You can parallel these as needed if one destination needs more drive current.

Best regards.

Bob Masta D A Q A R T A Data AcQuisition And Real-Time Analysis

formatting link
Scope, Spectrum, Spectrogram, Signal Generator Science with your sound card!

Vote
Twitter Facebook LinkedIn
M

snipped-for-privacy@daqarta.com (Bob Masta) wrote in :

Cool Bob .. I'll check that out .. thanks

mike

Vote
Twitter Facebook LinkedIn

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required