Thread: Harbor Freight Pressure Mat Hack ?

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I have read through a bunch of the forums looking for info on how to hack the alarm on the Harbor Freight Pressure Mat. My question is, does anyone know how to hack the alarm itself? Right now it sounds for a minute, and I would like to shorten it to 10 seconds or so. Can anyone help me with this? Thanks, FireAsh

The fixed length timer in the alarm box may be able to be hacked, but I'd need to see a clear pic of board. Depending on what's used as a timer, it may be as easy as changing a resistor. If the sound and/or time are burned into a chip, you're probably stuck with adding a secondary timer to shut off the alarm.

got a couple of pics, hope you can see what you need. I would even be happy if I had to eliminate the relay and only have it make any sound when it's actually being stepped on. Thanks for looking at this for me.

Try this, wet your finger and hold it across the leads on the black & gray capacitors while the unit is making sound. There is a good chance 1 of them will cause a change the amount of time the unit runs. When you identify the correct capacitor, you will probably be able to shorten the duration by replacing it with a smaller uf value. Or placing a resistor of high value might be a viable alternative if you have access to a few. Try placing 100K across the leads of the capacitor when you have it identified. If 100K makes it too short try 470K, if it is still to long w/ 100K try 47K, or as close to these as you may have around, keep going in the direction that works to get the duration you need. If you identify the capacitor, and need to buy something (nothing on hand) try picking up a 1 meg ohm trimmer potentiometer (variable resistor). Connect center and 1 of the outside leads across the caps and adjust the pot to change the time.

I will be the first to admit that you are talking way over my head Bobby. I think I'm just going to give up on this idea for this year.