Konami System 573

[jonhughes]

Not done anything PCB related for a while but needed to do this. The 573 wasn't saving settings and so every time I turned it on it was requesting the date settings which was becoming a bit irritating.

The problem lies with a M48T58Y-70PC1 Timekeeper SRAM. The battery in the chip has expired.

Here is the 573 PCB and the chip in question is under the insulation tape.

Exposed now. The problem with this thing is that it is flush to the PCB meaning access to the pins is only available from the solder side.I prefer to just cut suspect chips out (if they're not customs), happy to destroy them than do anything to the board trying to get them out. Trying to remove chips from certain PCBs can be a problem particularly on multi-layer PCBs - just like this one in fact.

Solder side of the board with 28 pins to de-solder.

I use maximum heat on the iron and use of plenty of flux. I have a solda-pult sucker but using it on this multi-layer is a complete was of time. Prime the pins. Heat the solder and mix with flux. I do this about 5 times. I then use de-solder braid to get remove the solder from the pins. It was a bit touch and go on three pins.

The three pins are numbers pin 26 for some reason and pins 14 & 28 which I assume must be GND and +5V since these were a bitch to clear. The braid causes a little scorching to the PCB but nothing noticeable. I find it the best way for me (on these multi-layer boards).

Here is the chip in question, now out.

Here is a socket in its place.

It's fairly neat on the solder side.

I've ordered a replacement for the far east for £4 delivered (it's amazing how things can get across the other side of the world for those prices, but I'm not complaining). Put the existing SRAM back in until the replacement arrives. Put everything back together and it's all good.

jonhughes2017-03-03 20:10:31

 

[Bensonrad]

Looks like you've done a great job there.

 

[jonhughes]

Thanks Ben,

Multi-layer PCBs are a pain. Before doing this I did some research and discovered that Craig has seen a lot of these sent in after people have had a go at them.

The multi-layer is the problem. I'm guessing that when you apply heat to the pins attached to the internal core layers the layer takes most of the heat away. I also find the solder has sort of fused or oxidised inside the eye. I can see why a lot of these end up being damaged.

Would be very wary if I was to attempt this again.

 

[Luigi]

You've got some solder skills, Sir

There's no doubt I would have destroyed the PCB while trying to remove this IC

 

[slowcade]

Nice job! I purchased a second 573 board which already had this chip socketed. That actually cost me just marginally more than sending it away for repair.

 

[virtvic]

I have one of these with exactly the same problem. I don't think I'll tackle this myself. Too scared about knackering the board.

 

[jonhughes]

I have one of these with exactly the same problem. I don't think I'll tackle this myself. Too scared about knackering the board.

I must admit I got about an hour into this and thought 'What have I done!'. As I mentioned, 25 of the pins are not bad to de-solder. Those three pins linked to the layer system are a nightmare.

One thing I forgot to mention - if you do end up with a soldering eye where the solder just won't come out I tend to drill the solder out very carefully. I use what can only be described as a 'pen drill' to remove it. I used this on those three pins. If you go at the pins with the iron for too long it ends up screwing the PCB up. Too much heat tends to kill things. I used this drill on all three stuck pins. I was fortunate to get the chip out by gently prying it (by hand and finger force) from corner to corner (no screw driver or you'll bugger up the PCB once again).

This little gem gets me out of all sorts of scrapes when there is stuck solder in the soldering eyes but you need to patient and careful when using it.

 

[darthsylly]

Fantastic work and fantastic tip. I will be ordering a pen drill for working on Sega System 32 boards - also a nightmare to de-solder. For me at least

 

[virtvic]

I remember reading about this memory chip (NVRAM of sorts?) and it needs decryption code (for the game) writing to it as well as it acting as a memory?

I was talking to a Swedish collector over the weekend who had an original Konami 80s classics cd rom and security cart that just wouldn't boot, but some 'hacked' cdroms worked just fine without a security cart.

Am I rememebring that if you ever do run any other cd roms, you can't ever run the original again? Some kind of suicide type of thing going on?

I'd like to be able to run the Bishi Bashi games and Salaryman Champ but I DON'T want to lose Konami 80s Classics.
virtvic2017-05-08 12:43:45

 

[Monstermug]

All the timekeeper rams from China are fake. Be warned! Bought one and it didn't have the notch to tell you where pin 1 was. They may work but battery will probably be either dead.

 

[Lid]

I remember reading about this memory chip (NVRAM of sorts?) and it needs decryption code (for the game) writing to it as well as it acting as a memory?

I was talking to a Swedish collector over the weekend who had an original Konami 80s classics cd rom and security cart that just wouldn't boot, but some 'hacked' cdroms worked just fine without a security cart.

Am I rememebring that if you ever do run any other cd roms, you can't ever run the original again? Some kind of suicide type of thing going on?

I'd like to be able to run the Bishi Bashi games and Salaryman Champ but I DON'T want to lose Konami 80s Classics.

I was wondering the same thing as I have read similar. I also have a 573 with a failed battery, in my DDR machine in my dinning room

. I contacted Craig at Giz10p about repairing as I have no chance in replacing the chip but never got around to getting the board out and sending it off. I just put up with the prompts and no high score saving.

When I got the DDR machine, it had some carts and discs for other versions of DDR in the back of it. I fancy trying out the other versions, and possibly trying to make the cart slot and disc drive more accessible, so I could swap them in and out easily. But I don't want swap a game out to find I can't start any of them.

 

[jonhughes]

All the timekeeper rams from China are fake. Be warned! Bought one and it didn't have the notch to tell you where pin 1 was. They may work but battery will probably be either dead.

Except the one I bought, works totally fine.