A logic probe oscilloscope or multimeter on pin can help you determine which is at fault. Varistors can be purchased from Great Plains Electronics. Commonly referred to as linear flippers [...]

LED locked on Remove all ICs except for U and if it is Stern. Memory Capacitor Prepping an MPU Board for Installation Alternate method installing . Before explaining how the computer makes all this work let summarize display driver has four inputs from [...]

Unfortunately between the amp and logic probe isn adequate cheaply hearing tone. Connect EPROM pin to jumper location . These are or byte ROMs at U and K [...]

Display problems. Although rare Bally did add strobe for some games such as Centaur Medusa and Spectrum. This enabled the programmers to concentrate defining their rulesets and lamp effects instead of tweaking timing within assembly code itself. Also use endof stroke switch [...]

If the board is producing no sound at all start by checking volume adjustment pot. The software is remarkably similar as well although Bally was more apt to use set operating system roms chip for several games whereas Stern opted customcompile their each most pairs . At least one DIP switch must be to avoid this [...]

How Bally Coils are Driven for Dummies. VDC GND AS Aux Lamp Driver . These were used to give tabs little more reinforcement so they don flex and break off [...]

Varistors can be purchased from Great Plains Electronics. Lamp Driver Board J Header Output Q KEY GND Bally AS Aux. After looking over the line cord plug inspect [...]

E means jump to . These tabs tend to break off. You should identify which under playfield solenoids any are used as such in your game and add fuse to the activation single thinner wire side of coil prevent software glitch from locking that . Next make certain that the EPROMs installed are valid. Closeup of the infamous Scanbe brand socket [...]

Check the chart below for specific games. Finally the lack of solid ground on lamp driver board will also cause lamps not to light. a burned out fuse of any amperage or voltage you were saving them just for such thing circuit breaker amps whatever require are Buy ones like Mouser Carling XBAA Tyco. Get rid of that battery now Some Options to Eliminate the NiCad board If is it recommended remove immediately [...]

While you re there if your display glasses are not new use small trimmer pot on near fuse and adjust high voltage to be VDC. Most failures of continuity to the MPU circuitry are due either connector pin female housing fractured solder joints header [...]

Keeping the leads short on switch capacitors might reduce their tendency pick up this stray RF machine. If battery corrosion made it to that connector is good idea add jumper the solder side of board from Pin and ground runs along outside [...]

These screws are not isolated from case of HV transistor. Switch problems Bally Stern x Matrix games use arranged as for total capability of switches [...]