Centipede mess

channelmanic

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Donor 3 years: 2011-2013
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Hey guys,

This Centipede board has been worked on by someone and it's a mess. I replaced a bad RAM on it and cleaned the ROM legs to fix some graphics issues and rebooting issues, but wanted to get some opinions on this:

IMG_5805.jpg


Have you ever seen a mess like this? Should it be undone or just leave it as is?

Thanks!

RJ
 
That is a 'Frankenstein' board. I have never seen anything like it before. So, it works like it is after your fixes? I would leave it alone if it works. :)
 
Depends on why it was done. If it was piggy-backed to replace bad parts without desoldering, then fix it. It it was done to fix some mystery issue that could take you forever to figure out, then clean it up to look better. If the board still doesn't work, pull it all off, make it original, then fix it...
 
holy gwokamoly batman!

looks like an mc1458 with something after it, confirm the ic type, if its a 1458 its a dual op amp so the additional circuitry makes some sense if its to do with audio.

then annotate a copy of your schematic page with the changes to see if you can figure out what the added "circuitry" does.

download the specs on the 1458 dual op amp ic from various manufacturers and compare their suggested implementation circuits.

it might be an undocumented hack to fix an issue. =)
 
I need to find a trackball to fit this board... all I have is a Happ Controls trackball.
 
Thanks!

This Happ one has 2 4 pin connectors. They are labeled A, +5, G, and B

The Centipede schematic calls for Horiz Dir, Horiz Ck, Vert Dir, and Vert Ck. Would the Happ one work on that? I've never messed with wiring up trackballs before.
 
Depends on why it was done. If it was piggy-backed to replace bad parts without desoldering........

i like this explaination better - a distinct possibility given the type of work done! =)

EDIT: MC14584 eh ? the caps etc make more sense now as pulse stretcher rc networks on some inputs! yeah it was a bit hard to read even at high zoom ! oh i'll just stop blatherin now.
 
Last edited:
Hey guys,

This Centipede board has been worked on by someone and it's a mess. I replaced a bad RAM on it and cleaned the ROM legs to fix some graphics issues and rebooting issues, but wanted to get some opinions on this:

Have you ever seen a mess like this? Should it be undone or just leave it as is?

Thanks!

RJ

If it works, I'd leave it alone. If it doesn't, then rip it all off, replace any related ICs that aren't the right part, and fix it from there.
 
I have seen something like that once before. I think that was a hack in order to use a different trackball than the one that came with Centipedes. I don't remember who made the Pede trackballs. It was either Wico and the hack was to use another brand or the hack was to use Wicos. As Andy said, what I can see of the circuit, it looks like they are either stretching or trying to invert the signals.

ken
 
Board works fine with the hack. I have another Centipede board here that works fine without the hack with the same trackball. Go figure.

I just wired up the trackball A/B wires to the horizontal and then the other A/B wires from the 2nd board to the vertical connections and it worked fine. Trackballs are pretty simple, except they sure get NASTY inside.

RJ
 
Thanks!

I'm now officially repairing Centipede boards. This was a customer's board.

I have another one I repaired today that I'll be tossing into my for sale thread.

RJ
 
Thanks!

I'm now officially repairing Centipede boards. This was a customer's board.

I have another one I repaired today that I'll be tossing into my for sale thread.

RJ


Hmm. Think I may have a Centipede that needs repaired. :)

Sounds like your are set for a track ball.
 
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