Press on press off

HI, I'm no expert in electronics, so I'm hoping that someone can help me... I have a Dewalt line laser that I want to come on when power is put on the leads from the battery terminals, and shut off when power is taken away... the switch is a press on/press off type so I would have to press the switch after each time power was restored to turn it on.... this is no good to me for this project.... I presume that there is something acting as a relay on the pcb.... it's all very tiny.. I'm wondering if I could solder a jumper across the terminals to have it come on automatically when power is switched on?... I did notice some 2302 transistors on the board, but I don't know if they are what I'm looking for..but if they are, would crossing the power and drain pins work? Thanks

by outinthewoodsnf
November 27, 2020

There's either a flip-flop or latching circuit there. The 2302 mosfets are probably a good starting point. I would get a meter and start measuring voltages from the button to the 2302's. if you get constant voltage when the button is pressed and then it goes away when you push it again, then you should be able to add a jumper to keep it in a constant on state. You could attach a temporary lead from the voltage side of the button and start poking around till it does what you're after, but I'd hate to see you ruin a nice laser level.

by JimmyG1976
December 26, 2020
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