Isolating the 50 V flasher circuits for LED flashers
Steps
- In coil test, note which coils fire for solenoids 3A, 4A, 6A and 7A (usually rarely used coils such as the knocker, drop target resets or poppers). Some games have nothing on one of them, for example Rollergames has no 3A.
- With the game on and the meter negative lead on ground (the coin door), find which lug of each of those coils carries power and mark that wire.
- Turn the game off and leave it off until every step is done.
- Solder a 1N4003, 1N4005 or 1N4007 across each of those coils with the band on the power lug. A reversed diode destroys that coil's TIP36C.
- In the backbox, find the auxiliary power driver board (the long board on the right below the power supply).
- Clip out diodes D3, D4, D6 and D7, just below the large TIP36C transistors at the top right, or cut one leg and lift them; do not nick the resistors or transistor legs.
- Power up; LED flashers no longer blink with the flippers.
Do not power the game on part-way through: it destroys the TIP36C transistors. The power-lug check is done with the game on; keep clear of the backbox line wiring.
Systems
Games
- Bad Cats
- Banzai Run
- Big Guns
- Black Knight 2000
- Bugs Bunny's Birthday Ball
- Cyclone
- Diner
- Dr. Dude And His Excellent Ray
- Elvira and the Party Monsters
- Jokerz!
- Mousin' Around!
- Police Force
- Pool Sharks
- Radical!
- Riverboat Gambler
- Rollergames
- Space Station
- Swords of Fury
- Taxi
- The Bally Game Show
- Transporter the Rescue
Related tips
- CPU and driver board transistors by position
- How a WPC coil, flasher or lamp driver chain works
- Which transistor drives which WPC solenoid and lamp circuits
- How a coil or flasher is switched: PIA to TTL to pre-driver to driver
- A coil or flasher energizes as soon as the game is turned on
- Flipper blows its fuse after a rebuild: diodes shorted by reversed power wires
- Launcher, scoop, VUK, one pop bumper and knocker all dead: failed TIP36C on the PPB board
- Kickback locks on as soon as its switch is hit and blows Q3: coil diode backwards
Source: How to modify System 11b and c Auxiliary Power Driver Board to Eliminate some flashers from blinking when flippers are engaged using LED Flasher bulbs