Stern Galaxy acting up again

[deep six]

Hadn't played the old galaxy for some time as the solonoids stopped working. Figured I would fire it up today and see if I could get it going.
At first it was booting up fine, 7 flashes on the LED, went into diagnostics and none of the solonoids would fire.
Checked the 1 amp slow blo fuse under the playfield only to find it blown.
Rooted around looking for a replacement but couldn't find a slow blo so whacked a normal 1 amp fuse in.
Ran diagnostics again and it got halfway through solonoid diagnostics firing each coil til the fuse gave out.
Rummaged around in the old box of spares and found a 1.5amp slow blo. whacked that in and ran diagnostics and all is good.
Except, .... it wouldn't go into game play. Things progressively got worse from this point.
Re-booted it and it hung on second flash.
Re-booted it again and got a single flash from the LED and then a pulsating beeping noise from the speaker but no second flash.
I usually get a beep accompanying every flash but this time got one beep and the aforementioned pulsating beep after that.
Not sure whats going on but it ain't happy...... Please Help

[Strangeways]

Sounds like a problem with the CPU board not booting correctly. Since it is an intermittent issue, I'd try re-seating the ROMs, CPU, PIAs, ROM and 5101 (don't touch the legs of this IC). I can almost guarantee it has the original sockets and they are playing up. You can re-seat all the connectors on the MPU board.

[deep six]

Yep, I was just thinking the same thing, just ripped the MPU board out and about to do some re-seating, what was that you said about the IC??
I have replaced the ram chips and the ram chip sockets previously

Cheers

[Strangeways]

The 5101 CMOS RAM (U8) is prone to static. You don't want to touch the legs as that will damage the chip 

[deep six]

OK, Just removed all the chips and replaced them, was as careful as possible to avoid touching the legs but had to carefully straighten a few and tweak them so they would fit back in the sockets.
I did note I had a bent over pin on one of my 5101 chips, carefully straightened it and put it back in.
put the board back in and tried to boot it up but got the same result as before, just one beep then a pulsating beep.
I know I bought a rebuild kit for the mpu board a while back. I probably have some new sockets I could solder in.
But then again, maybe its time to take a drive to Kens place and let him look at it

[Strangeways]

OK, Just removed all the chips and replaced them, was as careful as possible to avoid touching the legs but had to carefully straighten a few and tweak them so they would fit back in the sockets.
I did note I had a bent over pin on one of my 5101 chips, carefully straightened it and put it back in.
put the board back in and tried to boot it up but got the same result as before, just one beep then a pulsating beep.
I know I bought a rebuild kit for the mpu board a while back. I probably have some new sockets I could solder in.
But then again, maybe its time to take a drive to Kens place and let him look at it

If you are not comfortable with the repair, I would recommend Ken has a look at it for you. He has the text fixture and could probably fix it in his sleep !

[deep six]

Yep, sounds like I should be knocking on Kens door.
I just rooted around my box of spares and found the Big Daddy Deluxe MPU kit, I already used the 2 5101 ram chips and sockets out of this kit, but considering how I managed to bend one of the 5101 legs already .......

[deep six]

Hmmmm, weird, I let the machine sit for a while, then decided to pack it up, put the backglass back in. Figured I would power it up one last time and bugger me it booted up and went into game play

[Retropin]

As others have said... intermittent faults like this are 99% of the time due to poor connections unless you have some corrosion on the board from an old battery... this gradually eats through the tracks until the game will boot no longer. My guess is connections though... chip sockets or header pins... if the logic supply is not solid, it will drop out and the game will freeze up like this.
It may boot now but if the fault isnt fixed then it will crash during a game

[deep six]

Yep, spot on retropin, the game was working but froze half way through play.
I've re-pinned all the connectors and fixed the acid damage, looks like all thats left is to fit new sockets as you suggested.
Hmmm, to solder or not to solder, that is the question

[beaky]

if it has any original I.C. sockets then they need to go.
When you repaired the battery leak damage did you remove all the solder from the solder throughs and then re-flow the solder through the board?
Sometimes you will need to run a wire through the solder through and solder the wire from the trace on one side of the board to the trace on the other side.

I have circled the solder through pads I am referring to in the photo below, of course the board pictured needs the corrosion repaired and there are many more of these pads that can be affected by a battery leak.
  

[Boots]

I recently had a problem with a Bally that the board would boot with seven flashes and then do nothing except lock a couple of coils.
Ended up being the ROM socket, replaced that and all was good.

[deep six]

Thanks Guys, many thanks for all your help, as always this board is the best place for helpful info, Who wants an Aussie Pinball sticker, !! Beaky, I don't think I sent you any??
I put this job aside for the time being, just got too many projects on the go. I gotta cull some.
Cheers