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1  Using Arduino / Sensors / IR switch sensor to measure RPM debouncing. How? on: March 20, 2013, 08:40:41 am
I have this sensor:

http://www.miniinthebox.com/smart-car-to-avoid-the-obstacle-sensor-infrared-sensor-photoelectric-switch-201211270080034_p480362.html

I want to measure the RPM of a diesel engine in range 200..3000 RPM
I have connected the signal line of the sensor to pin 2 (interrupt 0) on the UNO.
With a simple sketch i'm able to read the pulses, but, here's the problem:

A pulse can trigger anything from 1 up to 9 interrupts!
So I presume the signal is not clean (i don't have an oscilloscope to check)
I have tried some software debouncing tactics, but with no luck (or the deboucing is too slow)

Can i clean up the signal with a schmitt trigger circuit?
Will it be fast enough?

Will a simple solution with a 4093 NAND schmitt trigger IC work, like here? :

http://yogibotics.blogspot.com.au/

..or do I also need "analog smoothing" first, and if so, can someone give me a link to such a
circuit, cause i'm not a real electronics expert..
Thanks
2  Topics / Home Automation and Networked Objects / Re: Project iCamper on: February 22, 2013, 09:13:52 am
Nice to see another person which has the idea to build a camper control panel  smiley
I have just (sort of) finished mine, it's my first Arduino project.
Check it out on:

http://508.winand.nl/?p=1087

(On the right hand side there is a translation option, just hover over the flags, you'll see)
The panel is not build in the camper van yet, which is still under contruction.
I have experimented with a gas sensor to detect gas leaks.
Works well, but the power consumption is arround 100mA, which is too much for my likings
(remember it has to be on all the time..)
I'm thinking of replacing that with measuring the weight of my LPG tank (I use a standing
LPG tank, so putting sensors underneath it should be simple)
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