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Old 12-09-2009, 03:21 AM   #11 (permalink)
mora
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Quote:
Originally Posted by Tweety View Post
The diode D1, what is it supposed to do really? Cuz right now it's not really doing anything a normal wire couldn't do...
My guess the intention is to protect the circuit? Ie swap ground and +12V and nothing goes poof?
Hey, glad to see you in this thread. You definitely know these things better than I do. I appreciate your time you spent replying.

Actually, I was wondering the same when I saw the circuit for a first time. I thought I could leave it out but kept it since I don't know if it has some meanings as protection. Remember, I have done nothing but placed components on a pcb. Didn't even pay a thought but I guess I really should have. Original one was on simple board with tin/wire bridges all around. Schematics are also made by the same guy. I should ask him what he was thinking when placing that diode there.

Quote:
Originally Posted by Tweety View Post
Then it really should be connected to the ground wire... Facing so that the ground flows out of the circuit is open, but nothing goes in that way, since that is what makes things go poof... Connecting ground to +12V won't make anything go poof... It just won't do anything hooked up that way, no lights, no magic smoke...

Move the diode to the ground connector and have it block the path into the circuit and it gives protection... As it sits now you can just replace it with a wire and the circuit will work the same...
Now I see, maybe the original plan was to do so, to prevent connecting meter reversed. Simple protection.

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