make sure your 5 volt supply is solid ...my sound would quit and score would blank out usually during multi-ball , thought it was a daughter board problem and damn near wiped out the mpu board trying to fix it .....turned out it was the 5 volt supply so I would definitely suggest reflowing all the solder joints on the supply , cleaning and replacing the heat sink compound on the transistor and cleaning the adjustment pot with contact cleaner ...also on every system 80B system I have .....I have had to replace the 470uf and the 10uf caps on the display board

I agree it would be better to change it to 1 million also I have an eprom burner and both types of chips if you need a beta tester

I put a couple of pieces of felt adhesive backed tape found in the sewing section at walmart on the wall of the wheel to slow mine down ....it would take so long that the ball did not register the number

Houston we may have an issue and don't know if anyone else has tried the new roms but this is what I got .....bookkeeping stats were weird .....could not set replay one ,two or three and got a checksum on prom one issue. PROM 1 F6E9 .....the 10 million shot did register 1 million but the machine was acting weird .....the stop on right flipper lites for the bumpers sometimes had two lights lit. Took the eproms back out and back to the programmer and reverified that no code was dumped ....both chips verified good

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this is what I did to my wheel to slow down the ball and while I was at it I took a cue from chuckwert and got one of those sticky clear things cut it flat and positioned it on the bottom side of the glass at the top of the ramp ....whollaaa damn ball doesn't smack the glass anymore at the top of the ramp ......I got this machine modified and the flippers have always been super hot .....thought about changing them but I like this thing the way it is ....its steep , its fast ....its fun. they also added blue leds to the top lanes , green leds to the bumpers and ramps .....I should probably go for an alternate translite to make it even better

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Just ordered 8 2864 chips ....yes I have a large wall wart that I use as an external power supply, I did 2 sets and they verified fine they are ST brand that are the 12.5v program and never had a problem before ......I used double write went back and read the buffers and they seemed ok. will try programming at a slower speed today if that doesn't work I will have to wait for the other chips (2864's) which are slated to be in next Tuesday

I erased them yesterday when they didn't work ...here is my question ....I did not have freeplay installed in my machine but I went to the website and used Prom 1 and Prom 2 under 708-M so they should have worked ?
If I get a chance today I will re-download the original files and burn the files at a -2 speed

got my new chips and downloaded a fresh set of files programed the new chips in the slow mode ....no runs , no hits and most of all no errors stuck them in the machine and got the same indications ...could not set anything in book keeping ......1,2,3 replay no response ....high game to date hit the credit button nothing no change ......10 mil shot registered 2 million tried it three times with the same results took them back out and put the old proms back in and the machine works as advertised. took the burnt proms back to the programmer and they verified just fine no errors . Some body else want to take a shot at this .......retired in this field for after 40 years on equipment that pilots and passengers lives depended on that makes working on a pinball machine childs play.....
let me know what you get ....my machine is running the original MPU board so dont know if that makes a difference

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It doesn't lock any solenoids or do anything dangerous to your machine if that's what your concerned about ......would be nice to see someone else get it working then I know its a problem with my machine.......I have done the following to my MPU ......Resoldered the daughter board.....installed Navram .....removed the battery and any assc corrosion and neutralized so could I still have a problem with the board ......maybe ........I got a spare swemmer board but it would not work (didn't like my 5v power supply) ...Installed a newer power supply version yesterday and boy was it touchy had to set it to 5.06 vdc make the machine happy ....any more or any less and it didn't like it. so maybe I will try the swemmer board with the new chips.