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September 22, 2013
Tutorial - Reaction Timer
about 5 years ago
I also swapped out the greenish led for a much brighter white one.
The tiny green light that comes with the button was quite dim.
I made it! There is one small error on the picture of the wiring.
The pin description for the signal to the digital readout says pin 2. That is correct.
However, The picture shows the wire on pin 3. oops.
This was a great project.
I ordered all the parts from the website, and they arrived quickly and in good shape.
The red box is a nice touch. It is easy to carve with a dremel.
The digital readout is bright and clear.
I used an arduino Uno model board for mine.
I will be taking it to work to see who is the quickest.
Thanks for the project !
about 6 years ago
Exactly. I am looking for one that holds 2 or 3 AA's.
about 6 years ago
Can I power a 12 volt 500 ma solenoid coil with this opto-isolator board?
I broke out both my voltages from an 8 AA cell battery pack. I'm using 3 volts on the input side (2 AA's), and 12 volts for the solenoid (8AA's). My input supply side signal is an analog output from a 3.0 volt ATmega328 chip (output A0 ). I have the output side on 12 volts to drive the solenoid coil. I don't want to fry the output pin of the atmega. If I add a 12 volt relay before the solenoid coil, will that help? Or is this board made to replace that also? I can also add a clamping diode on the solenoid coil if needed.
No public wish lists :(
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