RE: Question about blackened edge connectors...

This is common on most/all Atari PCBs that use the edge connector. Usually,
the problem is that over time you get a little oxidation on either the
ground pad or one of the 5/12v supply tabs. Not enough to cause an open,
but enough to increase the resistance. As a consequence, the voltage drops.
The AR PS senses this, and then boosts the voltage to compensate. Over
time, this will heat up and oxidize more, resistance increases, PS
compensates, repeat.. Sometimes the end result are pads that are completely
burnt up or the harness starts to melt.

To fix, you either need to repair or replace the damaged pad(s). You should
burnish them clean as opposed to sand -- sanding can remove too much of the
pad as well as scratch which leads to oxidation again. You also need to
inspect the connector and make sure that it clean. Note that the contacts
will lose tension over time and as they get hot -- it may be time to replace
the connector altogether.

With this type of problem, the sooner you fix it the less likely it is to
create a bigger problem.

Good luck, and have fun.

BTW: Did you grow up in Colorado?

> -----Original Message-----
> From: owner-vectorlist@synthcom.com
> [mailto:owner-vectorlist@synthcom.com]On Behalf Of Andrew Wilson
> Sent: Wednesday, August 22, 2001 7:13 PM
> To: vectorlist@synthcom.com
> Subject: VECTOR: Question about blackened edge connectors...
>
>
> My Asteroids Deluxe has been having trouble with its edge
> connector since I
> bought it. Occasionally it will fail to boot up, at which point I open up
> the machine and wiggle the edge connector, then power up the
> machine and it
> seems to solve the problem. I'd always assumed that maybe there was some
> oxidation building up on the tabs which needed to be scraped off
> by wiggling
> the edge connector, but I didn't worry about it much because I knew the
> "fix" and it didn't happen very often.
>
> Well, it happened again, and this time wiggling the edge connector didn't
> work. This time I ended up taking the board out and took a good
> look at it,
> and the topmost tab on the PCB board (the one that connects to GND, I
> think - I didn't have my meter or my pinouts handy) was blackened, and had
> peeled off the PCB a little bit. I took a little sandpaper and cleaned off
> the black stuff, and the game works again, but now I'm concerned that
> there's a more serious problem that I should try to solve instead of just
> ignoring it.
>
> I dimly recall that someone else had a problem like this a few months ago
> with their Asteroids, but I can't seem to find it in the
> archives. Is this a
> common problem with these PCBs? The game seems to work fine otherwise, but
> if someone can suggest a solution, I'd be much obliged.
>
> Thanks,
>
> Drew
>
> ------------------------------------------------------------------
> ---------
> ** To UNSUBSCRIBE from vectorlist, send a message with
> "UNSUBSCRIBE" in the
> ** message body to vectorlist-request@synthcom.com. Please direct other
> ** questions, comments, or problems to neil@synthcom.com.

---------------------------------------------------------------------------
** To UNSUBSCRIBE from vectorlist, send a message with "UNSUBSCRIBE" in the
** message body to vectorlist-request@synthcom.com. Please direct other
** questions, comments, or problems to neil@synthcom.com.
Received on Wed Aug 22 22:07:31 2001