help to build digital car speedo meter

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Thread Starter


Joined Oct 3, 2014

i start to build digital car speedo meter i have honda civic 93

i dont know Vehicle Speed Sensor output its frequency or voltage , mhz = volt = speed

i will use pic16f877a and LM2907 if output is frequency

and i need help to build circuit digram



Joined Jul 18, 2013
At one time the output was taken from the final shaft of the gearbox, now, electronically, I am not sure at what point they take it from, but the common way is by a hall or similar sensor.
Why use the LM2907? Keep it pulse timing instead of going analogue.


Joined Mar 24, 2008
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