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System 80b/Robo-War help needed

ronsplooter

ronsplooter

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Joined
Jul 21, 2011
Messages
6,481
Location
Nottingham
Alias
Chris
Calling Sys 80b experts @Poibug @myPinballs @JMP

I've put a few games on Robo-War now and have noticed a couple of issues:
  • When playing the game the coils (at least the flippers and bumpers) will stop working until the ball drains but then all be working at the start of the next ball. It happens a lot and feels like a tilt but there's no sound call and the playfield lights don't go off. Any ideas where I should start looking?
  • The the bass sound coming from the top speakers is distorted and crackly. I thought it might be a bad speaker but it sounds like it both sides when I disconnect one or the other speaker. I can't see any pots on the sound board to play with. So could it be that both speakers are bad or something on the sound board, maybe needs re-capping?
Ground mods have been done, there's a memory cap on the MPU board etc it's had the recommended work done as part of the restoration.

Also, what do people do about the NC slam tilt switch on the coin door, solder the two wires together to take it out of the equation?

Any advice gratefully received :thumbs:
 
Yeah, the door slam you could just solder them together

Sounds like the game over relay is deactivating- re coils/flippers or also possible losing temporarliy the 5v at the cpu board.
If one of the four Tilts is activated it would say TILT on the display

Regardless always a good thing to do is measure the 5v on various boards - especially the cpu board - if you put your meter on dc volts and measure across the capacitor c1 next to where the power comes in on the board at J1.
Reason is these incoming pins especially are prone to fatiguing thus you lose good contact on the board.Regardless is worth you checking it as it, IIRC has come from a country with slightly different voltage than here in the uk .Also worth quickly running a fibreglass pencil across the contacts on the cpu board.If ya aint got the fibreglass pencil or pcb eraser - well worth it.
Also has the main filter cap just in front of the coin box been replaced - if not do it!!

The volume pot on or around the coin door could be dicky but probably not.
Could turn it off and exercise i tup and down a few times and see if it improves , probably not tho.
Your idea re caps - most definately possible.
Incidently you have checked the connections on the speakers arn't reversed?And may as well just double check the speakers impedance?

Plus, IMO, and I am sure @JMP will agree - retapping the tranny to 200volts - thus giving you a bit more volts on the coils and you will actually have a chance of sensibly making the ramp shot- and if ya do that you will have to adjust the main 5volt pot on the opwer board9probably) so ya may as well get it out the way now.


Happy to try and help ya with any questiosn ya have - if I can i will.i know a bit about gotts so will endeavour to help!!
 
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Loss of bumpers flippers etc I would check the 5v feed to the control boards of pops and then as Poibug says the game over relay

I would rebuild the 5v supply immediately to and change to a fixed 5v design plus change that cab 12v filter cap.

As for the sound issue I would check the audio amp board first. A cap rebuild on this would be the starting point as the game is mono. You could also check the line out from the main sound board to see if it's clear there
 
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Thanks gents, plenty of things for me to go away and check :thumbs: I'm not around much this weekend so won't get chance to look at your suggestions till next week but I'll report back.
 
Managed to spend a little bit of time on this today and first thing I did was solder the slam tilt switch wires together to remove that from the equation. Also leaving the sound issue alone for now as the game reset/lock up issue is happening all the time and making the game unplayable.

I measured the 5v on the CPU board across capacitor c1 and it shows 5.85v which sounds too high. Could this be causing the problem and what do I need to tweak it down too...around 5.05v? I'm guessing this is because the game came from France?

I also managed to get it to go into the reset/lock up state a few times by either bouncing the ball around on the pop bumpers or hitting the slings. It does feel more like a lock up as it kills power to pops, slings and flippers and some lights come on and stay on, the special lamps in particular. As before though, as soon as the ball drains the game comes back to life unless it's ball 3 in which case the game stays in this locked up state and needs power cycling.

The cap in the bottom of the cab isn't orange (it's black) so I'm guessing this means that it's been changed? The CPU board has had some pretty significant work as per the pics below:

IMG_1066.jpg

IMG_1067.jpg

IMG_1068.jpg

IMG_1069.jpg
 
Just been playing with the 5v adjustment pot and if I turn it down so that the voltage across c1 on the CPU board drops below 5.8v then the game won't boot. There's a sweet spot somewhere around 5.75v where it makes the game go mental, flickering all the lights and firing all the coils.

Could the lock up issue be that when the slings or pops are firing (or maybe the flippers too) it's pulling the 5v on the CPU below this 5.8v limit? If I try cranking it to show over 6v across c1 am I going to damage things on the CPU board?
 
Hmmmm. 5.85v seems awfully high to me. Just got to nip out to drop a parcel off then will post a few more ideas
 
Right then, just reread your messages. Here are my thoughts :)

It looks to me that something isn't right with that cpu board, which isn't a surprise if i'm honest judging by the awful repair job on it. If the game won't boot until the 5v is adjusted to 5.85v then that sounds like something on the cpu board is wanting far too much 'juice', possibly a failing ic somewhere, or a bad connection, bad repair. Looking at it, it really could be anything on there, though possibly start with the cpu boards power connector. Measure the voltage at the 5v board and then at the cpu board closet to the connector end. Is there a difference?. A good cpu board should be fine and dandy at 5.05v no more and there should not be much of a difference between voltage tests board wise.

Another idea it to check for anything obvious regarding the slingshot switches and pop bumper switches. If there is a short on one of these or something is touching something it shouldn't, possibly the switch input could cause the cpu to crash or jump to the wrong point in the program etc. This isn't that likely though as normally if a switch is shorted to something bad, the buffer chips are fried, which tells you the issue.

Third idea is to put the game in test and check through everything tests wise noting anything odd. Then put it in switch test and test those switches you mentioned earlier and see if the switch test behaves itself.

Forth idea is the obvious get another cpu board or one of my new ones to rule out the bad repaired cpu. Of course connectors and power could still be a problem, but you'll know the board itself is good. Plus i wouldn't put anything else board wise in there you put the voltage back to normal 5.05v - 5.15v

Let me know how you get on


Jim
 
Did the cap on the Hollywood heat yesterday made quite a difference to the flippers.
5.8v yikes!
 
Thanks Jim, you have PM incoming re: a new board :thumbs: Seems daft for me to spend ages looking for a Robo-War, get hold of a cosmetically nice one and then not make the electronics spot on.

I will test the voltage coming off the 5v board to see how that looks and run the tests as you suggest and report back on those. One thing I have noticed is the 2nd O in ROBOWAR seems to light at the same time as the 1x insert.

I'm also going to inspect all of the ground mods to see if I'm happy with them and re-do where required.
 
not meaning to sound a tw@here but can ya check the voltage with another meter as can't believe the french owner was such an ejit to set it so damn high.France is only 10-20 volts different and it shouldn't count for that.IF it is that high it is pretty much causing a big stress on any 5v chip on any circuit board.Plus bearing in mind the fairly accurate guesstimate that pins are fatigued means,assuming your meter is right that the voltage could be even higher!check it at the output connector with the connector disconnected.If stuck phone me
 
I don't have another meter here but can go and grab my Dads this weekend and will report back :thumbs:
 
Re main filter cap All sys 80b ones have been black not orange.If connected remove the anti reset board,as,ironically they cause resets!poppers and slings are controlled separately, not by the cpu or driver , tho vibration of em firing could cause summat.TBH i would just treat it to a new cpu board, after voltage checks are satisfactory.BTW the pots on the power board are ****e
 
Check the pins on A1 J6 - they will have been acid damaged with the board and whoever repaired it may not have touched them...
 
Quick update to say Robo-War is now working :thumbs: Massive thanks to Jim @myPinballs for all the help and support, especially after I fried the lovely new board he'd made for me :oops:

Game now plays great but there are still a couple of things I need to look at:
  • The sound is still crackly and rough. I've fitted a brand new speaker upgrade kit from Keith @new forest pinball so I know it's not the speakers. I'm assuming the sound board so will pull it out of the game and take a look....any ideas on where to look are always appreciated :thumbs:
  • One of the insert lights in Robowar is either always on or on at the same time as the 1x bonus multiplier insert, need to confirm the exact behaviour. I'm assuming I need to replace a transistor on the driver board.
 
Hit the test button on the sound board, if its still crackly and rough then the problem is on the board, new capacitors and clean socketed chip legs. If not then its likely to be the connectors...
 
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ronsplooter said:
Quick update to say Robo-War is now working :thumbs: Massive thanks to Jim @myPinballs for all the help and support, especially after I fried the lovely new board he'd made for me :oops:

Game now plays great but there are still a couple of things I need to look at:
  • The sound is still crackly and rough. I've fitted a brand new speaker upgrade kit from Keith @new forest pinball so I know it's not the speakers. I'm assuming the sound board so will pull it out of the game and take a look....any ideas on where to look are always appreciated :thumbs:
  • One of the insert lights in Robowar is either always on or on at the same time as the 1x bonus multiplier insert, need to confirm the exact behaviour. I'm assuming I need to replace a transistor on the driver board.
Click to expand...


Re the sound. Can you tell if the crackle is isolated to one set of sounds/speech/music or is it everything?

The sound board is designed with various sections /channels that are mixed together before being outputed as a line out.

If it's everything then I'd start with a cap rebuild on the amp board not the main board. I have the parts if you need them :)
 
The insert lamp issue is resolved :thumbs: Turn's out that in my excitement when the game first turned up I'd trapped some wires when putting the head up. Wire's now un-trapped, thankfully no permanent damage and insert lamps working as expected.

On the sound issue, I took out the sound and amp boards and did the following:
  • Cleaned header pins/connector terminals on both boards with fibre glass pencil
  • Took out both the socketed chips on the sound board and cleaned the legs with fibre glass pencil
  • Re-flowed solder on the sound board header pins
  • The cap's had already been replaced on the amp board by a previous owner so I re-flowed the solder on their work
Unfortunately I'm still getting the crackle :( Jim, to answer your question I don't think the crackle is in all of the sounds....the voices sound fine as do the higher notes. It's more in the bass beat that you get the distortion and because that beat plays the entire game it's really noticeable. I'm assuming this points to an issue with that channel on the sound board but I have no idea where to go from here?
 
ronsplooter said:
The insert lamp issue is resolved :thumbs: Turn's out that in my excitement when the game first turned up I'd trapped some wires when putting the head up. Wire's now un-trapped, thankfully no permanent damage and insert lamps working as expected.

On the sound issue, I took out the sound and amp boards and did the following:
  • Cleaned header pins/connector terminals on both boards with fibre glass pencil
  • Took out both the socketed chips on the sound board and cleaned the legs with fibre glass pencil
  • Re-flowed solder on the sound board header pins
  • The cap's had already been replaced on the amp board by a previous owner so I re-flowed the solder on their work
Unfortunately I'm still getting the crackle :( Jim, to answer your question I don't think the crackle is in all of the sounds....the voices sound fine as do the higher notes. It's more in the bass beat that you get the distortion and because that beat plays the entire game it's really noticeable. I'm assuming this points to an issue with that channel on the sound board but I have no idea where to go from here?
Click to expand...

If it's the music that the issue then I can point you to certain caps on the main board to change and/or an op amp
 
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If it's the music that the issue then I can point you to certain caps on the main board to change and/or an op amp
Click to expand...

Thanks mate, I'll PM you later although I can't see anything on the sound board that looks like a traditional cap to me :thumbs:
 
worth re checking the cables that you trapped.Funny enough I was doing otime in work on Saturday, to replace a twin met cable that had been trapped and was causing a short
 
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Ok so Chris doesn't know this yet (a small surprise coming!), but I received his 80b sound board a few days ago to have a look at this crackle fault, after we'd spent a few weeks going back and forth with me suggesting things to try/change to solve it!

So have been spending the last 2 days on this trying to track down this blooming annoying fault. What an absolute PITA this has been!!!

So here it is - > FIXED :) Now need a few beers! and some counciling ;)

 
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