why can't I knock 'em out?

RayWest

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Game works fine now, I found a bad trace with the help of LyonsArcade and was able to resolve the problem.
This was actually my first "board repair"

GREAT HELP,
Thank you
 
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Is the microswitch wired correctly? Do you have it wired as normally open (NO), or normally closed (NC)? And are you sure the proper wires are connected to the KO button? I think Punch-Out! has some extra wire connections on the control panel harness that aren't used.

I have a PunchOut that the K.O. button doesnt work. I replaced the microswitch, and it wire has continuity all the way down to the PCB, any other advice?
Thank you
 
Yes,
Im hitting the button when the KO is highlighted, and still nothing..... I checked the switch and everything looks good at that end, maybe something with the boards......
 
Usually problems like this are pretty simple, if you're positive that it's all wired up fine with good continuity, look at the schematics and track down what chip/resistor pack, etc. it runs to first from the edge connector. Then check continuity all the way through to that. If it's still making good connection, it's got to be whatever chip it runs to before it joins all the other switch inputs, or a resistor or cap it runs through before it gets there.
 
I looked it up, the Knockout button comes in on a grey wire on pin 50, then runs through RM1, which is a resistor pack that's 1k, then runs through RM6 which is a 68ohm resistor pack, then ties to pin 4 of 1r, a 74LS240. Your problem should be one of those if it's truly on the board, because after that they all join together, since all the others work it can't be any deeper.
 
I looked it up, the Knockout button comes in on a grey wire on pin 50, then runs through RM1, which is a resistor pack that's 1k, then runs through RM6 which is a 68ohm resistor pack, then ties to pin 4 of 1r, a 74LS240. Your problem should be one of those if it's truly on the board, because after that they all join together, since all the others work it can't be any deeper.

I checked with information that you gave me, and sure enough there was a bad trace, did a quick jumper and Im "KNOCKING EM OUT"!!!!!!!

Thank you so much for this, this was actually my first "board repair" and I couldn't have done it without your help.
 
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