Doctor Who
Bally, 1992You're currently viewing posts by Pinsider rdoyle1978.
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Quoted from yellowghost:Should be connected that way. But by a trace. Not a jumper wire. I think one leg of every reciever shares a trace.
That’s correct, all transmitters and receivers on each board share a ground wire, the other traces are individual to each diode
Quoted from manadams:Try electrical tape on the ends to prevent any external light exposure, blacking out the area and cleaning the optos usually fixes a lot of problems.
Or make a new shroud from the template
Quoted from dsuperbee:Even with the shroud, you will still need some sort of tape to seal the edges.
Not sure why? The original design still works perfectly fine
Quoted from dsuperbee:Mine didn't until I taped the edges, and neither did the one I am rebuilding for a friend.
No kidding? That is unusual - neither of the DW I’ve owned required that. I wonder if the optos had been replaced with more sensitive ones?
Quoted from tjprice222:Holy crap...I’m about to throw this onto assembly off a cliff. Thank you all for the replies. Here’s where’s I’m at:
I replaced all of the original optos and confirmed those were working. All we’re registering except the 5th - it was really flakey. I confirmed it was due to the wire jumper because the solder pad was gone. If I held pressure on the solder joint with my finger, it was fine but as soon as I relieved pressure, it was flakey again.
My solution was to order replacement boards from Marco. I installed both yesterday and now only two optos register in edge test mode - 1 and 2. I can get them all to register if I place the boards literally touching optos to receivers but as soon as I put them in the bracket holder, only the first two register consistently. Not to mention the new receivers are taller than the old ones and are interfering with the mushroom buttons.
I’m kind of at a loss for where to go from here. I guess I’m trying to see if anyone else has had issues with the Marco boards. I should have just gone Great Lakes modular. Any other recommendations for an easy fix?
Sorry to say, but just order the ones from GLM. You will never want to disassemble the mini-PF again. It’s worth the $$
Quoted from tjprice222:I made sure it wasn’t that. The receivers on the Marco boards are definitely taller. By the way, the bottom of my opto bracket appears to be bent or tapered. Can anyone confirm this is normal?
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The way that bracket is bent is usually a result of someone installing washers to offset the taller optos
Just get a Dremel and grind the black optos down a bit. They will still work fine and you’ll have the clearance you need. Avoid the washers!
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Mt Zion, IL