Using an external switch as a dip switch...

modessitt

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I have a test board that can output standard or medium resolution for monitor bench testing. Only one dip switch needs to be changed to change resolution. I have this board mounted on a wall, and would like to have an external switch on my bench that I can flip to change the resolution easily from my chair, rather than going over and flipping the little dip switch with a little screwdriver.

I assume that if I leave the normal dip switch off, I can connect wires to both sides that go to my external switch. But I'm wondering whether I have to worry about wire resistance (about 18" each way) or switch resistance when doing so...
 
I wouldn't think so. If it does, you've got two options. 1) Put a larger gauge wire in to drop resistance and see if it helps. 2) Put a cheap transistor like a 2222 in place of the dip and drive the transistor with your switch and +5V.

Personally, I'd try extending it with some 20ga and see what happens, if that fails I'd drop in a transistor and skip the larger gauge entirely. Actually, as I write this, I'm thinking I'd flip the board over and throw a transistor in parallel with the switch. If you decide to revert later, just clip the transistor out.
 
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That'd be no problem at all. There's almost no current going through the switch, so the little amount of resistance has almost no effect. There's probably a 10k pullup or something on the board, so as long as you're not anywhere near several k resistance, you'll be fine.

DogP
 
It will work fine, done it before for a pause switch on a pacman. Had a toggle that would switch dip 8 at the same time cut out the speaker.
 
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