Problem with Strikers 1945 PCB

Ozymandiaz1260 · Post by **Ozymandiaz1260** » Tue Mar 25, 2008 6:29 am

Usually when you turn this board on it makes this little nintendo like sound, kind of like "ba-DING" or something. I tried turning it on for the first time in a couple of months and it just goes "bababababababababa", just repeating the first part of the sound over and over again. The screen also flashes in time with this. It worked just fine the last time I played it, and it's just been sitting in bubble wrap for the past few months. I looked at the board and there doesn't seem to be anything physically wrong with it. Do you guys have any idea what the problem could be, and how I can fix it

Post by **system11** » Tue Mar 25, 2008 11:10 am

It sounds like it's resetting really quickly at a guess.

Possibilities:

1) PSU is shorting - some arcade supplies will do this in a loop resulting in rapid popping sounds and flashing screens. Really you should notice this as it will make a ticking sound too.

Possible issues:
* Shorted components, usually a filter cap to cause this.
* Some longer chip/cap legs on the back of the board are bent over and either touching eachother, or touching tracks.

2) CPU is crashing and restarting.

Possible issues:
* Poor seating of socketed chips.
* Degraded ROM data.
* Failure of other components.
* See above for bent legs problem.
* Voltage is too low for reliable operation.

Ozymandiaz1260 · Post by **Ozymandiaz1260** » Tue Mar 25, 2008 1:33 pm

bloodflowers wrote:* Voltage is too low for reliable operation.

There's a potentiometer on my PSU that I think might control the 5 line, do you think messing around with it is a good idea? I already went over the back of the board with a magnifying glass and physically rocked all the sockets to make sure they were in well.

Post by **system11** » Tue Mar 25, 2008 5:03 pm

Don't touch it until you have a meter to measure the +5v feed under load. Best to use an old fashioned needle one if you can, it'll make it much more obvious if the PSU is resetting instead of the board.

dpful · Post by **dpful** » Tue Mar 25, 2008 5:14 pm

Does it reset with other boards?

Ozymandiaz1260 · Post by **Ozymandiaz1260** » Tue Mar 25, 2008 5:39 pm

dpful wrote:Does it reset with other boards?

Nope, everything else works just fine. This is the first time I've tried using this board since I fixed my Egret II PSU, and I think I probably moved the pot when I had it all apart.

Ozymandiaz1260 · Post by **Ozymandiaz1260** » Wed Mar 26, 2008 5:46 am

The potentiometer was the problem. I know it probably wasn't very smart, but I turned it up and the board messed up even more. I turned it down and it works just fine now

Hopefully it's not too low for any of my other boards now.

Radiant · Post by **Radiant** » Wed Mar 26, 2008 6:11 am

can you please measure the voltage on your PSU?!

You can easy damage an expensive PCB so buy a 20$ multimeter and adjust it to 5 - 5.1V

Post by **system11** » Wed Mar 26, 2008 9:17 am

Yes, what he said. Running them over-voltage will definitely lead to premature failure. This is very, very important. Some games have less tolerance than others, and will simply zap the first time you plug them in if you're running anywhere past 6-6.5v.

Ozymandiaz1260 · Post by **Ozymandiaz1260** » Wed Mar 26, 2008 7:46 pm

I turned it down, not up, and I moved it by the smallest amount that I possibly could. This is dangerous?

dpful · Post by **dpful** » Wed Mar 26, 2008 8:39 pm

If you want to test it on a cheap-tough board, you'll see that, as you turn it up, the screen will brighten (contrast will increase), and then the board will crash (or not) or perhaps break. As you turn it down, the game will usually pause (crash), and then not start again (till you turn it up).

You should check the voltage. You're probably running everything a little high.

I thought only a few older boards (salamander for example) had such a low tolorance that they would break with a high 5v. I wouldn't be surprised if some bran-new ones were built the same way. Most boards from the 90's are very tough and can tolerate some variation and still function(probably wear out faster). Best not to take chances and measure it.

Before I was electronical savy, I would turn them down till they paused, and then turn it up a bit to find the right voltage. Nothing ever broke, but I'd use a multimeter now. -you never know, some board might need voltage outside of 5 to 5.1v. Most bootlegs need a much higher 5v.