Hobby motor sized tachometer
Hobby motor sized tachometer
(OP)
Mech guy here who's out of his element ;)
Looking to build a very inexpensive tachometer with small LCD display for a project using hobby sized motors (think R/C motors or smaller). I'm guessing I need either a mini inductive pickup or opto device wired into an LCD but I have no idea where to start looking. I deal with machine control systems (plc's and the like), so basic electrical I'm OK with. It's this small scale component stuff that I'm very uncomfortable with.
Total cost target is roughly $20. Is this something that's doable with off the shelf stuff? Any guidance would be appreciated.
Looking to build a very inexpensive tachometer with small LCD display for a project using hobby sized motors (think R/C motors or smaller). I'm guessing I need either a mini inductive pickup or opto device wired into an LCD but I have no idea where to start looking. I deal with machine control systems (plc's and the like), so basic electrical I'm OK with. It's this small scale component stuff that I'm very uncomfortable with.
Total cost target is roughly $20. Is this something that's doable with off the shelf stuff? Any guidance would be appreciated.





RE: Hobby motor sized tachometer
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If we learn from our mistakes I'm getting a great education!
RE: Hobby motor sized tachometer
For really low power consumption, you can also experiment with a little magnet glued to shaft end (if possible) plus a pick-up coil. That will not work at low speeds but OK above a few hundred RPM.
There are LCD units with built-in counters. One is available at http://www.pongrance.com/ddfc-cc.html and there are lots of others.
If your need is one off and you don't mind the looks, you can use a DMM with frequency range. The three dollar units do not seem to have frequency. But add a few dollars and you should get what you need.
If you need 1000+ units, you should have someone make them for you by your specification.
Gunnar Englund
www.gke.org
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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...
RE: Hobby motor sized tachometer
After proof of concept with the $1.99 motor, we upgraded to a $14.00 motor that had better bearings for longer expected life.
Bill
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"Why not the best?"
Jimmy Carter
RE: Hobby motor sized tachometer
RE: Hobby motor sized tachometer
RE: Hobby motor sized tachometer
motor and the electronics are all there. Good
for up to about 10 kHz, IIRC. Been a while. :)
<als>
RE: Hobby motor sized tachometer