Got a Bicycle Computer Today

[valterra]

$10 at Target, or $15 for a more advanced one.  The advanced one had lots of features we wouldn't use, except it did say it gave the temperature.

I set it to 1667mm as suggested in another post, and tested it.  As far as I can tell, it works correctly.  Just have to multiply the kp/h by 10 to get the RPM.

Anyhow, before I went through any trouble of climbing up onto my roof, I cut the wires and put a 500 foot spool of Cat-5e between the sensor and the computer.  Tested again - same results.  Yay!

I thought there'd be something fancy like the magnet creating voltage spikes that the computer measures.  The very faint clicking sound tells me that it is a simple reed switch.  The GOOD news about this is that if the sensor gets ruined by the elements, any Normally Open reed switch should work as a replacement.  Surplus Center has them for about 2 bucks.  As confirmation, I quickly shorted out the wires many times and saw the reading on the computer.

Now if I could just translate it into my ACTUAL computer easily (read: CHEAPLY) I would be all set!

[tecker]

All the ebay elcheapos have an rpm setting

[valterra]

Cool.  I may try one for my next genny.  For now, the (.) in the middle doesn't bother me.

[SparWeb]

Since the sensor is a simple reed switch, you could feed the pulses into any pulse-counting data logger.  Depending on the setup, the reed switch will need +V supplied.

I have dreams of connecting a cycle computer reed switch to my PicLog, but counting the AC pulses works (barely) well enough to prevent me from diving in.

[ghurd]

Could we get a few examples?

[valterra]

That piclog looks interesting!

Especially since whenever I hook up a new meter, all I want to do is stare at it.

It wasn't windy today, but the "max speed" on it says 685 rpm.  Whoa nelly.  I can't wait to see what happens during a real blow.

(This is on my 4' Ametek genny with crappy blades).