Leaderboard

Wow, it's been nearly 5 years since I last posted in this thread!!! Just had a batch of MMM's in to sort. Most faults on these boards get cured by swapping out all the components in the battery area including the RAM. There can also be the odd broken via and corroded tracks but easily rectified with rivets and patch wires. One board which I'd had a few weeks previously had stopped working so I knew it was going to be a nightmare. On power up it would bleep about every second, flash a few lamps and motor drives and the 7 seg would go on and off too. Sometimes, very rarely, it would go into attract mode but not credit and then again sometimes it would credit but only on one denomination of coin???? After about 3 days of head scratching I was getting nowhere although I did discover some more faults that would have affected the lamp matrix overload (if it ever ocurred). So here I am on day 4 and I've got no idea what's going on, nothing is making any sense and the fault condition varies every now and then. Now I have two different game chips, one is 4 ROM chips (Cash Drop) and the other is Roulette which is 3 chips. I always use Cash Drop as it confirms all ROM sockets are Ok. So lo and behold with 3 chips in it runs a treat..... hmmm put the four chips back in and socket 4 if I move the chip with a little touch it boots fine or fails. Out with the socket and in with a new one. Not the easiest job in the world as the solder is grey and crumbly on the top side. A slight diversion here... A method I use to extract old sockets with crumbly solder is to apply heat with the iron tip (approx 370c) to the top side of the pin and when it melts the solder on the underside use a screwdriver blade to push the pin flat to the board (ie force it upward). Of course the socket will be ruined but it's knackered anyway. I find this breaks the seal and the socket can be removed a fair bit easier. Lots of flux is essential of course and the usual caveats apply don't attempt this unless you know what you are doing. Back at the ranch... With the new socket in the chip now is a snug fit whereas before you could extract it with just your fingers and of course it boots and runs fine. Phew!

Yeah that’s me. Not got a clue, I just hack away 😛

Many thanks for the kind offer. I've invested in a Desolder Station and it was a good investment. The socket is done...gradually working through the board now to see what else needs replacing. There's a fair bit of corrosion