Data East/Sega

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1 Introduction

Data East/Sega pinball used a board set with minor differences from 1987 to 1995. This boardset, like most hardware of this generation, is very derivative of Bally/Williams System 11 hardware.

Data East Standard DMD Board Set, this from a Star Wars

The following boards are typical of what you will find in a Data East backbox.

  • RED - Power Supply
  • BLUE - CPU
  • YELLOW - Playfield Power Board
  • GREEN - Sound Board

The first two games, Laser War and Secret Service, did not use a PPB board, and were equipped with a flipper power supply (very similar to the Williams System 7, 9, & early 11 flipper power supply). Secret Service used an MRB-1 (Mega Resistor Board) which was mounted to the back of the body of the cabinet.
There can also be two additional boards, not including satellite boards which were used such as a shaker motor driver board, a magnet control board, etc.

  • Games with solid state flippers will have a flipper control board name the TY-FFASI board. This board is located on the left side of the lower cabinet. Games which have more than three flippers, Baywatch and others, use two flipper control boards.
  • Display controller boards are mounted behind the displays. DMD controller boards have a separate CPU and communicate to the main CPU via a ribbon cable.


2 Games

For an extensive list of games produced by Data East and Sega, see the List of Data East Games.

The following table lists regular production games based on their circuit board (PCB) and system generations.

Clicking on the individual game name will open a new page dedicated to that particular game. Several of the games have their own coil assignment chart list on their page.

Game List and Board Version
Game (Manufacture Date) CPU Power Supply PPB Display Sound Flipper Notes
Laser War (3/87) DE-0262-2
or 520-5003-00
or 520-5003-01
520-5000-00 Not used 2x 7 digit A/N,
2x 7 digit N,
1x 4 digit N
520-5002-01 No PCB
3 lug coil and EOS switch
Uses 520-5001-00 Flipper Power Supply
Secret Service (2/88) 520-5003-02 520-5000-00 Not used (see notes) 2x 7 digit A/N,
2x 7 digit N
520-5002-0? No PCB
3 lug coil and EOS switch
Uses 520-5001-00 Flipper Power Supply and 520-5015-00 MRB-1 (Mega Resistor Board)
Torpedo Alley (8/88) 520-5003-02 520-5000-00 520-5021-00 2x 7 digit A/N,
2x 7 digit N
520-5002-0? No PCB
3 lug coil and EOS switch
Time Machine (11/88) 520-5003-02 520-5000-00 520-5021-00 2x 7 digit A/N,
2x 7 digit N
520-5002-0? No PCB
3 lug coil and EOS switch
Playboy 35th
Anniversary (5/89)
520-5003-02 520-5000-00 520-5021-00 520-5002-0?
ABC Monday Night
Football (9/89)
520-5003-02 520-5000-00 520-5021-00 520-5002-0?
Robocop (01/90) 520-5003-02 520-5000-00 520-5021-00 520-5030-00 520-5002-06
Phantom of the Opera (4/90) 520-5003-02 520-5000-00 520-5021-00 520-5002-0?
Back to the Future (6/90) 520-5003-03 520-5000-00 520-5021-00 520-5030-00 520-5002-01-09
The Simpsons (10/90) 520-5003-03 520-5000-00 520-5021-02 2x 16 digit A/N
520-5030-00
520-5002-03-12 520-5033-00
Checkpoint (2/91) 520-5003-03 520-5047-00 520-5021-00 128x16 DMD
520-5042-00
520-5002-03 First pinball machine with a DMD display
Teenage Mutant
Ninja Turtles (6/91)
520-5003-03 520-5047-00 520-5021-00 128x16 DMD
520-5042-00
520-5002-03
Batman (8/91) 520-5003-03 520-5047-00 520-5021-00 128x16 DMD
520-5042-00
520-5050-?
Star Trek
25th Anniversary (9/91)
520-5003-03 520-5047-00 520-5021-00 128x16 DMD
520-5042-00
520-5050-?
Hook (5/92) 520-5003-03 520-5047-00 520-5021-00 128x16 DMD
520-5042-00
520-5050-?
Lethal Weapon 3 (8/92) 520-5003-03 520-5047-01 520-5021-00 128x32 DMD
520-5052-00
520-5050-? First DE usage of 128x32 display
Star Wars (12/92) 520-5003-03 520-5047-01 520-5021-00 128x32 DMD
520-5052-00
520-5050-00
Rocky & Bullwinkle (2/93) 520-5003-03 520-5047-01 520-5021-00 128x32 DMD
520-5052-00
520-5050-?
Jurassic Park (6/93) 520-5003-03* 520-5047-02 520-5021-05 128x32 DMD
520-5052-00
520-5050-02 520-5033-02 Motor Control board mounted under playfield

Uses a shaker motor

Last Action Hero (10/93) 520-5003-03* 520-5047-02 128x32 DMD
520-5052-00
520-5050-? Uses a 520-5068-00 magnet control board

Uses a shaker motor

Tales from the Crypt (12/93) 520-5003-03* 520-5047-02 128x32 DMD
520-5052-00
520-5050-? 520-5033-03 Uses a shaker motor
The Who's Tommy (1/94) 520-5003-03* 520-5047-02 128x32 DMD
520-5052-00
520-5077-00 520-5076-03 Uses a servo motor board for the blinders

Uses a shaker motor

WWF Royal Rumble (5/94) 520-5003-03* 520-5047-02 128x32 DMD
520-5052-00
520-5077-00 520-5080-00 (2 used) Uses a shaker motor
Guns N' Roses (7/94) 520-5003-03* 520-5047-02 128x32 DMD
520-5052-00
520-5077-00 Uses a 520-5068-00 magnet control board

Optional shaker motor supported with latest software

Maverick (10/94) 520-5003-03* 520-5047-03 192x64 DMD
520-5075-00
520-5050-? 520-5076-00 First usage of 'super' 192x64 display
Mary Shelly's Frankenstein (1/95) 520-5003-03* 520-5047-03 192x64 DMD
520-5075-00
520-5077-00
Baywatch (2/95) 520-5003-03* 520-5047-03 192x64 DMD
520-5075-00
520-5126-02 520-5080-00 (2 used)
Batman Forever (7/95) 520-5003-03* 520-5047-03 192x64 DMD
520-5075-00
520-5126-02

* Extra pins at CN3 for printer. See the CPU section for more information.

3 Technical Info

3.1 The Data East Board Set

Data East used several different board generations. It is important to be able to identify the different versions when performing diagnosis and testing.

3.2 Recommended Documentation

Although it is not completely necessary to fix a Data East or Sega pinball machine, having a game specific manual can be extremely helpful, and is recommended. The game manual includes detailed information such as:

  • Lamp matrix mapping and location
  • Switch matrix mapping and location
  • Coil and flasher lamp mapping and location
  • Game rules
  • Unique playfield parts list including a rubber ring list and locator
  • Game specific wiring connections, lamp, and coil diagrams
  • Circuit board schematics
  • CPU, display, and sound ROM locations
  • Circuit board jumper settings
  • CPU version compatibility amongst current and previous games
  • Diagnostic and troubleshooting information
  • Theory of operation of some specific boards

As of 2014, service bulletins for Data East and Sega games are no longer archived on the Stern Pinball website.

3.3 The Wiring Color Code

Data East / Sega never adopted a color coding system. Instead, the wire color was marked accordingly in the associated documentation, (ie. a white wire with a blue trace is referred to as WHT-BLU, yellow with red is YEL-RED, black is just BLK, etc.).

3.4 Connector Designations

Data East / Sega did not use a board numbering system to any of the specific boards used in a game. In other words, documentation referred to boards as the following:

  • PS = Power Supply
  • CPU = CPU
  • PPB = Playfield Power Board
  • Sound = Sound Board

The naming convention for the connector on each board is notated as CNxx followed by a consecutive number, starting with "1" (ie. CN1, CN2. . .CN10, etc.).

According to the Data East Star Trek 25th Anniversary Pinball schematics/manual pp44; there are two connectors which do not follow the CNxx designation. These are 2F1 and 2F2 which connect to the main transformer (secondary side) at the bottom of the cabinet.

3.4.1 Burned Connectors

There are several connectors which are known to go bad after 10s of years of repeated thermal cycling of the system. The connectors become fragile; connector resistance goes up and the pins either heat up and/or melt it's housing. These connectors become an intermittant issue which can cause unexpected malfunctions which are difficult to troubleshoot. Author's Star trek machine gave intermittent incorrect sound effects and display resets.

Check the secondary transformer side connector; 2F2 which is located at the bottom of the cabinet and contains 2 sets of 6.3VAC GI illumination circuits. An example of a burned connector:

A Burnt 2F2 Connector

If this connector looks charred or looks like it got hot; replace it. At this time; a direct replacement for the connector is not known; however, A functional replacement can be purchased from Digikey under the following part numbers:

DigkeyPN MFG MFG PN Description
A1453-ND TE Connectivity 1-480703-0 CONN Cap 4POS 94V-2 UNI-MATE (female)
A1452-ND TE Connectivity 1-480702-0 CONN Plug 4POS 94V-2 UNI-MATE (male)
A25375-ND TE Connectivity 350551-3 CONN Socket 14-20AWG TIN Crimp
A25375-ND TE Connectivity 350551-3 CONN Socket 14-20AWG TIN Crimp

You'll need 1 of each of the first two, and there is a minimum buy of 10ea of the last two of which you'll need 4ea.


A toasty "wafer" used at connector CN1

Check CN1 on the Power Supply (PS). A bad connector is shown on the left. Remove the connector. Check to ensure the rounded PCB pins are not blackened with oxidation. If the connector feels loose, it's time to replace it. An exact replacement is available. Molex part number 09-18-5121 can be acquired from Mouser.com as 538-09-18-5121 Pin & Socket Connectors PCB MIXTERM 12P.


3.5 Switch Matrix

Data East uses an 8x8 switch matrix to control all switches except the test button switches and the special solenoid switches (only games which use reflexive CPU boards). A general discussion of the switch matrix can be viewed here.

3.6 Power Supply

Data East made several revisions to their power supplies during production to support different display (small, medium, large) and flipper combinations (2, 3, 4).

Data East 520-5000-00 power supply


Part Number 520-5000-00
This power supply was used on games with alphanumeric displays such as "The Simpsons". It creates both +100 and -100 volts to operate the plasma score displays. Typical problems with this board include:

  • Burned general illumination connections and connectors.
  • Pins on CN1, called a "wafer" connector, burn. You can safely exchange the unused pins at positions 5 and 8 for burned pins in a pinch.
  • The fuse clips are brittle, and fracture easily or lose their tension, a common theme across all Data East power supplies.
  • This power supply is compatible with the D-8345-XXX power supply from Williams and vice versa.


Data East 520-5047-00 Power Supply


Part Number 520-5047-00
This power supply was used on the five games (Checkpoint, Teenage Mutant Ninja Turtles, Batman, Star Trek, and Hook) which used the smaller 128 x 16 DMD. One thing which makes this power supply stand out at a glance are the two large 10W power resistors installed on the unit. Other things which make it different from the power supply used with a "standard" 128 x 32 DMD are:

  • The use of MJE340 and MJE350 high voltage transistors versus MJE15030 and MJE15031 transistors.


Data East 520-5047-01 Revision A Power Supply


Part Number 520-5047-01 Revision A
Revision A High Voltage section:

  • Has no resistor R17
  • The Zener diode at D10 is a 1N4764 and is tied to ground
  • Zener diode D11 is a 1N4743
  • Connector CN7 has three pins to drive the GI relay on the power supply


Data East 520-5047-01 Revision B Power Supply


Part Number 520-5047-01 Revision B
Revision B High Voltage section:

  • Has a 1.5Kohm 1/2W resistor at R17
  • The Zener diode at D10 is a 1N4743 <--- Note: Different from previous board revision
  • Zener diode D11 is a 1N4764 tied to ground <--- Note: Different from previous board revision
  • Connector CN7 has three pins to drive the GI relay on the power supply


Data East 520-5047-01 Revision C Power Supply


Part Number 520-5047-01 Revision C
Revision C High Voltage section:

  • Has a 1.5Kohm 1/2W resistor at R17
  • The Zener diode at D10 is a 1N4743
  • Zener diode D11 is a 1N4764 tied to ground
  • Connector CN7 has three pins to drive the GI relay on the power supply


Data East 520-5047-02 Revision A Power Supply


Part Number 520-5047-02 Revision A

  • Has a 1.5Kohm 1/2W resistor at R17
  • The Zener diode at D10 is a 1N4743
  • The Zener diode at D11 is a 1N4764 tied to ground
  • Connector CN7 has two additional pins that carry positive and negative unregulated 12 volts.


Data East 520-5047-02 Revision B Power Supply


Part Number 520-5047-02 Revision B
The -02 power supply is backwards compatible with games that use the -01 power supply.

File:DELargeDMDPS.jpg
Data East Large DMD Power Supply 520-5047-03


Part Number 520-5047-03
This power supply was used for Data East games with the large format DMD display. Since the large DMD displays had their own power supplies, this board did not contain circuitry to create the high voltages DMD displays require. It provides 5, 12, and -12VDC only.

3.7 CPU Board

  • 520-5003-01 (Version 1) - Reflexive
Data East 520-5003-01 CPU Board. This picture shows the first revision still labeled with "DE-0262-2". Compared to later boards marked with 520-5003-00 and 520-5003-01 part numbers, this revision has fewer jumpers.


The version 1 MPU was used only for the early production run of Laser War. Later production of Laser War used the Version 2 board.

The version 1 MPU contains only 2K of CMOS battery backed RAM, that being a 6116. The board can not accommodate a larger memory chip like the 6264. Consequently, this board probably won't work in later production Data East games since they probably take advantage of the expanded memory. The "Data East Test PROM" does not work with this revision of the board either.

  • 520-5003-02 (Version 2) - Reflexive
Data East 520-5003-02 CPU Board from Time Machine


This revision of the Data East MPU increased the RAM size to 8K by replacing the 6116 with a 6264 RAM.

  • 520-5003-03 (Version 3) - Non-Reflexive
Data East 520-5003-03 CPU Board from Jurassic Park (note -04 label from factory)


This revision of the Data East MPU removed the "reflexive" circuitry that typically controlled pop bumpers and sling shots. See the following section.

3.7.1 Reflexive Versus Non-Reflexive CPU Boards

Version 1 and 2 Data East CPU boards are reflexive. Simply stated, reflexive CPU boards are boards where the 6 special coil drive transistors were enabled by a special coil switch input. These coils were typically pop bumpers and slingshots. Each assembly had its own switch, which was not part of the switch matrix, and was responsible for enabling its associated coil when closed. This implementation is almost identical to Williams System 11 Special Solenoids.

Version 3 boards are non-reflexive. Non-reflexive boards use 6 special coil drive transistors, however, the switches responsible for enabling these coils are part of the switch matrix.

Version 3, non-reflexive boards are backwards compatible, and can be used in a game which would typically use a version 2 board. Conversely, version 2 reflexive boards are not forward compatible in games which use a version 3 board.

3.8 Playfield Power Board (PPB-1)

The PPB-1 board is Data East's answer to Williams' auxiliary power supply and interconnect boards created during the System 11B era. The PPB board consists of the four GI string fuses, current limiting resistors for the flashers, up to (not all PPBs are fully populated) five TIP-36c transistors, the 50v bridge rectifier, an array of diodes and a relay for coil multiplexing, and several other 32v and 50v power fuses. Some versions added a varistor, while others didn't.

  • 50v coil board
  • 520-5015-00
Data east 520-5021-00 PPB-1 Revision A board
Data east 520-5021-00 PPB-1 Revision B board



  • 520-5021-00

The only discernible difference between the 520-5021-00 Rev A and Rev B boards is the addition of a varistor on the revision B board.

Data East 520-5021-05 PPB-1 Board




  • 520-5021-05

3.9 Sound Board

  • 520-5002-0x series
    • 520-5002-00
    • 520-5002-02
    • 520-5002-03
Data East 520-5002-03 Sound Board


  • 520-5050-0x series
    • 520-5050-01
    • 520-5050-02
    • 520-5050-00
    • 520-5050-03
Data East 520-5050-00 Sound Board


Data East 520-5077-00 Sound Board


  • 520-5077-00 - This board is similar to the 520-5050-0x series. It was redesigned to allow up to four 27040 EPROMs for voices and sound effects. It has a different pre-amplifier design than the 5050 series, but uses the same MB3730A power amplifiers.
Sega 520-5126-02 sound Board (Front)
Sega 520-5126-02 sound Board (Back)




  • 520-5126-02 - This board is very similar to the 520-5077-00 design. The power amplifier section was redesigned. It is reported that it is interchangeable with the 520-5077-00. The sound section of the later White Star boardset is almost a 1:1 copy of this board.

Starting with the 520-5050-00 DE used the BSMT2000 sound DSP. The two PAL chips on all these board revisions are identical and can be interchanged with the ones in the White Star CPU board.

3.10 Solid State Flipper Board

  • 520-5033-0x series
    • 520-5033-00
A two channel Data East Solid State Flipper Board, 520-5033-00




    • 520-5033-03
Data East 2nd Generation Solid State Flipper Board, 520-5033-03, as found on Jurassic Park




  • 520-5070-00
  • 520-5076-00
  • 520-5080-00
Data East Rottendog Aftermarket Flipper Board (FLP023)



This board was re-engineered to use MOSFETs. It is compatible with a great many DE games via DIP settings.

3.11 Display Board

  • 520-500x-00 Master Display
Slave Boards
520-5004-00
520-5005-00
520-5006-00
520-5007-00
  • 520-5014-01
  • 520-5030-00
Data East 520-5030-00 Alpha-Numeric 16 digit display


520-5030-00 - Alphanumeric 16 digit display used on games Monday Night Football through The Simpsons (5 games total).

Data East 520-5042-00 128 x 16 "small" DMD Display (front)
Data East 520-5042-00 128 x 16 "small" DMD Display (back)


520-5042-00 - Used for the 128x16 line dot matrix displays on games Checkpoint through Hook (5 games total).

Data East 520-5052-00 128 x 32 "Standard sized" DMD Display (front)
Size Comparison between 128 x 32 and 128 x 16 DMD Displays


520-5052-00 - Used for the "standard" sized 128x32 line dot matrix displays on games Lethal Weapon 3 through Guns N' Roses.

Placeholder for Sega 520-5075-00 192 x 64 "Large" DMD Display (front)
Sega 520-5075-00 192 x 64 "Large" DMD Display (back)


520-5075-00 - Used for the large 192x64 dot matrix displays on games Maverick through Batman Forever (4 games total).

3.12 DMD Controller Board

Data East 520-5055-00 Dot Matrix Controller Board




520-5055-00 - Used with "standard" sized 128 x 32 dot matrix displays

3.13 Satellite Boards

3.13.1 Shaker Motor Board

Data East / Sega 520-5065-00 Shaker Motor Board


Shaker motor board part number 520-5065-00. This single sided board is pretty simple. However, being a single sided board, it is subject to fractured solder joints on the large current limiting cement resistors. If your shaker motor is not shaking, remove this board and check for failed solder joints.

3.13.2 Magnet Control Board

Data East / Sega 520-5068-00 Magnet Control Board





520-5068-00 - Used on games such as Last Action Hero and Guns 'N Roses

3.14 Accessing Bookkeeping, Settings, and Diagnostic Modes

Solid state pinball machines typically have a built in system for audits and adjustments. Data East/Sega used two types of auditing systems. The first system was Ease-A-Just and was used on Laser War through Mary Shelly's Frankenstein. The Portals system was first used in Baywatch and was used for all machines after.

3.14.1 Ease-A-Just

The Ease-A-Just control panel


The East-A-Just system is very similar to the menu system in Bally/Williams System 11 machines. The control panel is located in the cabinet just inside the coin door. The forward/reverse (green) button is an up/down positional switch and the step (black) button is a momentary switch. To enter the East-A-Just system press the step button. If the green button is in the down position the game will enter the diagnostics menu. If the green button is in the up position the game will enter the audits and adjustments menu. Diagnostics are game dependent so check your game manual for specifics. All games do have a switch test with the diagnostics section that can be used to diagnose switch problems. To exit the Ease-A-Just system hold down the Step button. This will rapidly send you to the last setting and will put the game in attract mode.

3.14.1.1 Setting Free Play

Data East machines hide many adjustments under a 'Expand Adjustments' section, including the free play adjustment. To set free play enter the adjustments section of Ease-A-Just by pressing the black button while the green button is in the up position. This will put you in 'Audit' mode. Now put the green button in the down position (reverse) and press the black button (step). You are now in the adjustments section. The last adjustment is typically 'Expand Adjustments'. Change this adjustment to 'Yes' to see many more adjustments, including free play. Adjustment values are changed by pressing the game start button. See: Expand Audits and Expand Adjustments, below.

3.14.2 Portals

To be completed. A brief explanation of the Portals system is in each game manual.

3.15 Setting the Level and Pitch of a Data East Game

Bubble Levels Located Underneath the Left Apron Card


+++Need to research which game this was first used on+++

4 Problems and Fixes

4.1 Entering Diagnostics or Audits

Data East used only two coin door buttons to enter diagnostics or audits / adjustments.


The two buttons pictured at left allow the operator to enter the Data East built in diagnostics or audits. The green button is a two position button. When the button is in the down position, pressing the black button will cause the game to enter diagnostics. When the button is in the up position, pressing the black button will cause the game to enter audits & adjustments.

4.2 Expand Audits and Expand Adjustments

The Data East Audits and Adjustments settings are limited to a subset of the all that can actually be set. The "menu" can be "expanded" to review and/or change additional parameters by selecting the "Expand Audits" and "Expand Adjusts" option. When this option is presented, press the game start button. Additional Audits and Adjustments may then be accessed.


4.3 ROM Size and CPU Jumper Settings

Location of Jumpers J4 & J5 on Data East CPU Board


There is a simple rule of thumb for J4 and J5 jumper settings. This rule applies to all games which use either the version 2 or version 3 CPU board. If two game PROM chips are used at position 5B and 5C, jumper J4 must be installed and jumper J5 must be removed. This applies to games from Laser War to Batman.

If a single game PROM chip is used at position 5C, jumper J5 must be installed and jumper J4 must be removed. This applies to games from Star Trek 25th Anniversary to Batman Forever.

The exception to the rule is Laser War. If a version 1 CPU is used in Laser War, only PROM chip 5C is used. The jumper settings should be J4, J6a, and J7a installed, and J5, J6, and J7b removed. If a version 2 CPU is used in Laser War, and PROMs are used at positions 5B and 5C, jumpers J4, J5a, and J6a must be installed. Likewise, jumpers J5, J5b, and J6b must be removed.

The Easy Button

There is an easy and convenient way to eliminate futzing with jumpers after the first the time. That is to install jumper J5, remove jumper J4, and burn the game's software into a single 27512 ROM. The Data East "Test PROM" works with this configuration as does Leon's Test ROM.

The general command to accomplish this in a "DOS box" is...

  • copy /b ROM-at-5B-Image.256 + ROM-at-5C-Image.256 SINGLE-ROM-at-5C-Image.512

For earlier games, like "The Simpsons", that used a 27128 at location 5B, simply double the 27128 image during the copy command to fill the entire 27512 image. That is...

  • copy /b ROM-at-5B-Image.128 + ROM-at-5B-Image.128 + ROM-at-5C-Image.256 SINGLE-ROM-at-5C-Image.512

4.4 Fuse Clips

Data East used fuse clips on circuit boards as opposed to fuse holders. These clips are prone to cracking and causing intermittent connections. They cannot be repaired, and should be replaced when cracked. The clips do have a correct orientation. When installing them make sure the "tabs" on the portion that grasps the fuse is oriented outwards. Inserting a blown fuse between the clips when installing new ones helps with achieving the required spacing, and ensuring that the clips do not get installed "backwards".

Fuse clips are located on the power supply, playfield power board (PPB), solid state flipper board, and some of the satellite boards.

4.5 PPB Board Issues

Common issues include:

  • Burnt GI connector #Burned_Connectors
  • Dead or shorted TIP36C transistor
  • Bad / broken fuse clips
  • Cracked header pins (cold solder joints)
  • Burnt board from overfusing fuse F5

4.5.1 Fuses on the PPB Board

The documentation for the PPB board in several Data East games is very lacking. In some cases, the fuse value is not illustrated, while in other cases, the fuses are not even shown in the schematics at all. The fuse values should be the following:

  • F1 - 5A Slo-Blo (GI Lamp Circuit)
  • F2 - 5A Slo-Blo (GI Lamp Circuit)
  • F3 - 5A Slo-Blo (GI Lamp Circuit)
  • F4 - 5A Slo-Blo (GI Lamp Circuit)
  • F5 - 5A Slo-Blo (50V Coils - Pre Bridge Rectifier BR1)
  • F6 - 5A Slo-Blo (32V Flashers - Post Relay)
  • F7 - 3A Slo-Blo (32V Coils and Flashers - Pre Relay)
  • F8 - 4A Slo-Blo (50V Coils - Post Bridge Rectifier BR1)
  • F9 - 5A Slo-Blo (50V Coils - Including Flippers - Post Bridge Rectifier)

Early PPB boards did not have fuse designations at F7, F8, and F9

4.6 MPU Board Issues

4.6.1 System 9 CPU Board 7-Segment LED Codes at Boot Up When Working Properly

TBD

4.6.2 System 11 CPU Board LED Flash Sequence at Boot Up When Working Properly

Data East CPU - Location of diagnostic LEDs


Much like the Williams System 11 CPU, the Data East CPU performs a basic diagnostics procedure and produces a series of LED flashes to indicate potential boot issues. The CPU automatically tests the PIAs, RAM and EPROMs at each boot.

With all tests passed, the LEDs illuminate in the following sequence at power-on:

  • The PIA and +5V LEDs illuminate immediately
  • Approximately 1/2-second later the PIA led is turned off and the Blanking LED illuminates
  • +5V and Blanking LEDs are illuminated until the game is turned off.
  • If a failure is detected on major board components, the PIA LED will display a flash code:

When the PIA led stays on do not assume that one of the 6821 PIAs is bad. A boot failure due to a completely unrelated error might just have occured. If you bench test the board you can also use WMS System 11A to 11C roms to check it out. The diagnostic routine is much superior to the one in the DE rom. If you use WMS U26 and U27 roms J4 must be set. You can combine both roms into a 27512 in which case J5 needs to be set on the DE CPU. Everything will work. Some of the special solenoids are connected to different pins but for bench testing who cares? V2 and later DE boards use a 8K ram. The WMS software will not be able to dectect errors in ram space above the 2K limit.

PIA LED Flash Sequence
PIA LED Suspect Component Location
Stays On One of the 6821 PIAs various
Flashes 1 Time 6064 RAM 5D
Flashes 2 Times EPROM 5B
Flashes 3 Times EPROM 5C


4.6.3 Display Operation at Boot Up When Working Properly

4.6.3.1 Alphanumeric Games

This is a stub.

4.6.3.2 Small 128 x 16 DMD Display
Data East "small" DMD Display display code version
Data East "small" DMD Display CPU code version

When a Data East game with a small 128 x 16 DMD display is powered on, the first thing shown on the screen is the display code version. Next, the CPU code version is displayed. This information is provided so the operator can verify the correct display and game software versions are installed. Once the display and game code versions have been displayed and the game has successfully booted, the controlled lamps should start to "dance". The game is now in attract mode.

4.6.3.3 Standard 128 x 32 DMD Display
Data East Standard DMD Display display code version
Data East Standard DMD Display CPU code version


When a Data East game with a standard 128 x 32 DMD display is powered on, the first thing shown on the screen is the display code version. Next, the CPU code version is displayed. This information is provided so the operator can verify the correct display and game software versions are installed. Once the display and game code versions have been displayed and the game has successfully booted, the controlled lamps should start to "dance". The game is now in attract mode.

4.6.3.4 Large 192 x 64 DMD Display

TBD.

4.6.4 Open the Door Message

"Open the Door!" Message upon boot up (128 x 16 DMD)


Games with the smaller 128 x 16 DMD display will sometimes display a message at power up, which states "OPEN THE DOOR!". The game is requiring the user to open the coin door, before allowing the game to successfully complete the boot process. The purpose of the message is to alert the user, that the backup RAM memory has not been preserved since the last power down. Possible reasons for the memory not being preserved are:

  • Batteries are not installed.
  • The batteries are providing insufficient power to retain the memory.
  • The batteries are installed incorrectly and not providing power to the RAM memory.
  • The battery holder is not functioning properly or has been compromised.
  • The batteries have leaked.
"Open the Door" Message upon boot up (128 x 32 DMD)


This message appears on some games with 128 x 32 standard DMD displays too (not 100% if all games have this or not). In addition to the message on the DMD, the controlled lamps will not strobe until the boot sequence has successfully completed.

You should be able to open the coin door then close the door, and the game will complete boot up.

If you've ruled out the batteries (as stated above) as the reason for seeing this message, there are other possible causes.

First, check diode D25 which is located just to the right of the batteries. You can remove the batteries and check the diode with your meter set to "diode check" the traditional way. Or, you could set your meter to DC volts, place the black lead on the ground TP at the top of the board, and place the red lead on the banded side of D25. Your meter should read about 4.2VDC. Now move the red lead to the non-banded side of D25. Your meter should read about 4.6VDC. The difference between 4.2VDC and 4.6VDC is the typical .5 to .7 VDC drop across the diode. If that voltage drop isn't measured, or the firs measurement was zero, then the diode has failed open and is not allowing battery backup current to flow.

Finally, measure for about 4.2VDC on the bottom right pin for the RAM at location 5D. RAM 5D is located just below the game ROM. If you measure 4.2VDC at D25 and not at RAM 5D, then there is a break in the PCB trace between the two, or the RAM socket has failed, or the RAM isn't seated well. The chip can sometimes be moved when the game ROM is changed due to their proximity on the board. If you've completed all these steps successfully and you still see the 'Open the Door' message, there is a good possibility that the RAM chip at location 5D has failed.

4.6.5 Relocating the Battery from the MPU board

The aftermath of batteries which leaked
A detailed view of the extent of damage done. Note that the area inside the yellow rectangle is potentially at risk


Relocating the 3xAA batteries off the MPU board or installing other alternatives for memory retention is always a good idea. Leaky alkaline batteries are the #1 killer of pinball boards.

One option is to install a remote battery holder, and place the battery holder somewhere below all the other boards. This ensures that even if the remotely located batteries leak, they won't leak onto (or even drip onto) components of the MPU board. Use good quality alkaline batteries, mark the date of replacement with a Sharpie, and replace the batteries annually.

Another option is to install a memory capacitor. This method is considered to be better than a remote battery holder, because memory capacitors are not prone to leakage like alkaline batteries. The only drawback is that the memory capacitor has to be properly recharged to be effective. If a game has the potential of sitting dormate without being turned on for extended periods (typically months), the memory capacitor may not hold the memory.

A third option is to install a lithium battery with a battery holder. Lithium batteries are much less likely to leak than alkaline batteries, and they do not need to be recharged.

Data East MPU Board with Remote Battery Pack


Adding a connector between the battery pack and the MPU board is a good idea. In doing this, the battery pack can easily be removed from the MPU board. Plus, if the batteries are forgotten, and do leak, the MPU board may not have to be removed to add another battery pack. A 3 x AA battery holder is the typical recommended replacement. If only a 4 x AA battery holder is available, a jumper can be soldered in the first battery position. Likewise, a diode can be placed in this position instead. This will prevent the batteries from being charged and 'cooked' by the game if blocking diode D25 on the MPU board fails. Keep in mind that an added secondary diode to this circuit will decrease the voltage passing to the RAM memory, if D25 is still good. Install a 1n4001 or 1N4004 diode in the position closest to the last + terminal (where the Red Wire exits). The banded side of the diode must be pointing in the direction of current flow, which is towards the (+) terminal marking on the MPU board, and away from the battery pack.

On the MPU, solder the battery cables: positive (red wire) to the bottom right pad and ground (black wire) to the middle right pad.

D23 and D25 Diodes Highlighted on a Data East Version 3 MPU Board


Since the MPU board is already out, another good practice is to check the D25 blocking diode. An open blocking diode will not allow the battery pack voltage to pass through to the non-volatile memory, and the newly installed battery pack will be ineffective. Conversely, a shorted blocking diode will allow the board's +5vdc logic power bus to pass through to the battery pack. This in turn, will charge the batteries, while the game is turned on. Alkaline batteries do not like being charged. They will heat up, and fail prematurely, (rather quickly). In worse cases, the new batteries can even leak or explode if charged. Testing the D25 diode is quick and easy, and worth the trouble checking it out. When in doubt, replace the D25 diode with a 1N4148, or add a secondary 1N4004 to the battery pack. Once again, if a secondary diode is added, it will decrease the voltage passing to the RAM memory, if D25 is still good.

Testing the D23 diode is a good idea too. The D23 (1N5817) diode is used to keep the backup batteries from powering the MPU board when the power is off. Evidence of a failed D23 diode are batteries which fail prematurely.

After adding a remote battery pack, and while the board is still out of the game, it is a good practice to measure the battery pack's voltage at the B+ test point on MPU board. All battery packs are pretty cheaply made, and failures "out of the box" are somewhat common. Checking to make certain the battery pack is functioning before reinstalling the MPU board in the game will save some headaches.

4.6.6 Installing a Memory Capacitor Instead of Batteries

Installation of an "H" Style Memory Capacitor, and replacing D25 with a wire jumper.


A memory capacitor is a great choice for memory retention, provided that the game will be turned on more frequently than not. If the game will not be turned on for several months, the memory cap may not stay charged. In turn, the memory may not be retained.

It is recommended to use a 1F (Farad) 5.5v "H" style memory capacitor. Other styles of memory caps will work, but an H style fits perfectly into the existing "+" and "-" holes where the factory battery holder was installed. When using a memory cap, blocking diode D25 must be removed (or jumped), and a 0 ohm jumper should be installed. The purpose of removing the diode is to allow the memory cap to be charged when the game is turned on.

Installation of a "Pi" Style Memory Capacitor, component side of board.
Installation of a "Pi" Style Memory Capacitor, solder side of board.


Another style of memory cap has both leads coming out the bottom, spaced about 1/4" apart, and looks like the mathematic symbol for "pi" when viewed from the side. The original holes for the positive battery connection on the PCB can be quite handy for installing this type of cap. Insert the positive lead of the cap through the small hole and the negative lead of the cap through the large hole. On the solder side of the board, cut the trace between the small and large holes, and add a jumper as shown in the picture on the right. The jumper connects the negative lead of the cap to board ground. The same jumper mentioned above, replacing D25, is also required.

4.6.7 Data East CPU Board Alkaline Damage Area

A handy guide to assist component replacement at alkaline damage ground zero.


So...you didn't get those batteries off the MPU board...for shame...for shame.

The diagram at left shows the component parts you may need to clean up the board. Typical alkaline damage abatement methods should be used (vinegar wash, scrub with brass brush, rinse vinegar away with isopropyl alcohol or LOTS of water, sand as necessary). Be sure to check under the 6808 processor socket for damage also.

Note some component parts are a bit odd, like the 33.2K resistor. A 33K resistor may be safely substituted.

4.6.8 Stuck Low Blanking Signal

Data East CPU Board - Key Circuits Identified


4.6.9 Stuck Low Reset Signal

Data East CPU Board - Key Circuits Identified


4.6.10 Connecting a Logic Probe to CPU Board

Data East CPU Board - 5V and Ground Test Points
Data East CPU Board - Logic Probe and PC Power Supply Connected




Data East CPU boards have the +5V and ground test points located just above the battery holder's upper right corner and to the left of connection CN17. Connections can be made to the appropriate pins on CN17, but it is much easier just to use the test points.

4.6.11 Using a PC Power Supply for Bench Testing

Data East CPU Board - 5V and Ground Test Points
Data East CPU Board - Logic Probe and PC Power Supply Connected



The only voltage needed to power a Data East CPU on the bench is +5VDC. Data East CPU boards have the +5V and ground test points located just above the battery holder's upper right corner and to the left of connection CN17. Connections can be made to the appropriate pins on CN17, but it is much easier just to use the test points.

4.7 Power Supply Issues

4.7.1 Voltage Selection Jumper Pinout

The 9 pin connectors used are Molex 19-09-2099 (butterfly connection w/jumpers) and Molex 19-09-1099 (connection on transformer pigtail).

9 Pin DE Transformer Power Configuration, configured for US 115V systems.


Jumper settings for 115V should be as follows:

  • Pin 1 - black - 115v "hot" input
  • Pin 7 - white - 115v "neutral" input
  • Pins 2 and 3 jumped together
  • Pins 8 and 9 jumped together


4.7.2 Similarity to the Williams System 11 Power Supply

The Data East Power Supply is very similar to the Williams System 11 Power Supply. It creates (or passes on) all of the voltages necessary for the game to operate, including...

  • 5VDC for the MPU (12VDC is not used / needed with a Data East MPU board - no "on board" sound circuitry and reset circuit only uses 5VDC)
  • 5, 12, 68, -98, and -110VDC for the Dot Matrix Display (for games with a standard 128 x 32 or a small 128 x 16 DMD display)
  • 18VDC for the lamp matrix
  • 34VDC for coils
  • 6VAC (or so) for general illumination lamps
  • 5, 12, and -12VDC for the sound board
  • 5VDC for the DMD controller board (games which use a standard 128 x 32 DMD display)
  • 12VDC for the large 192 x 64 DMD display

The power supply also contains a 24VDC relay used to turn general illumination on/off.

The 5VDC power circuit explained (in work)

  • The board receives about 9VAC at CN1, pins 10 and 11.
  • 9VAC is full wave rectified into about 12 and -12VDC by the bridge rectifier at DB1.
  • The 9VAC continues to capacitor C2, a 100uf/25V electrolytic cap that is used as part of a voltage doubler circuit that provides operating power for the 723 regulator. D2, D3 and C3 comprise the remaining components of the Greinacher type voltage doubler. Failure of any of these four components will cut power to the LM723 regulator and affect 5VDC operation.
  • Unregulated 12VDC is presented to the LM723 5V regulator at pins 11 and 12.
  • R6 is used for short circuit detection. Under ideal conditions (output not shorted or overloaded), there should be a very small voltage drop across R6. If the power supply is shorted -- there will be a large voltage drop across R6. Pin 3 of the regulator will detect the difference and turn down the series pass transistor TR5 in the presence of a shorted output.
  • R2 and R3 are connected to the LM723 in a voltage dividing configuration. R2 and R3 together with R4 establish the output voltage levels (5VDC)

4.7.3 "Arcing" on the 520-5000-00 Power Supply

A rehabbed DE 520-5000-00 Power Supply that exhibited arcing due to a leaky electrolytic capacitor.
The corroded DE 520-5000-00 Power Supply prior to rehab. The area where power arced is clearly burned (circled in yellow), and liquid electrolyte can be seen near the bottom of the board.


A problem that might be unique to this particular version of the Data East power supply is that sometimes an electrolytic capacitor on the board will leak, arcing, and creating a short between the horizontal trace and a "via" circled at left. This shorts high voltage to the -12VDC power circuit and may result in C53 on the sound board being damaged. Sometimes, the electrolyte on the board will cause it to "sparkle" when power is turned on.

Note that in the picture, the trace has been partially removed, along with the through hole, and a jumper placed on the back of the board connecting the bottom (unbanded side) of D8 to the left side of the 680 ohm resistor at R13 (shown with the red line).

The electrolytic contents as well as any carbon created by the arcing must be completely removed, necessitating a radical traceectomy like this at times.

A closeup of yet another 520-5000-00 power supply with a electrolytic cap at C7. The damage hasn't caused a problem on this board yet, but soon will.


4.7.4 Missing 5VDC

An overview of the DE small DMD power supply components. Note that D10, a 1N5379 110V 5 watt zener diode is obsolete and no longer available.


An overview of the power supply.

God's eye view of capacitor C2, leaking.


A second view of C2, leaking.


A common reason for the lack of 5VDC is failure of the capacitor at C2. This 100uf/25V cap sometimes fails and begins to leak it's contents onto the circuit board. After a period of time, the caustic contents of the cap begin to eat into the board's copper traces. Eventually, the 5V generation path is severed.

Closeup of trace completely severed at C2.
Closeup of trace completely severed at C2 on an Alphanumeric version of the power supply.


These pictures show the 5VDC trace completely severed by the hungry caustic leakage from C2 (left) and enough damage to cause the circuit to open (right).

A portion of the DE Power Supply schematic, with C2 circled.


Note C2, circled in the schematics at left, and it's position in the 5V generation path. It's failure interrupts the path.

The LM723 5VDC voltage regulator.


Another common cause for loss of 5VDC power is failure of the LM723 regulator. Measure and compare the DC voltage at pins 4 and 5 of the regulator relative to board ground. If the voltages differ, the regulator has failed. Socket and replace the regulator.

4.7.5 Burned Connector Pins

Burned 9VAC input pin. Often this pin is burned to a crisp. This one isn't too bad.
A common "hack" was to cut the wire of the burned connector, then solder that wire directly to the back of the board. Ouch! Not recommended.


The 12 position "wafer" connector (CN1), which provides AC power input from the transformer secondary, often ends up with burned pins. Complete replacement of this connector is recommended should it become burned. The female housing may be reused, but it's good practice to repin both sides of a burned connector.

In a pinch, "male" header pins on the CN1 wafer may be swapped with "male" header pins at CN2, pins 1, 2, 4, or 5, as those pins are never used.

The severely burned wafer connector at CN1 here has been replaced with parts currently available. Pins 5 and 8 are not populated as those connections are not used.


The 12 position "wafer" connector (CN1), can be replaced with currently available parts, shown at left. The original "wafers" are difficult to find and pricey.

Crispy General Illumination Power Connector. This connector should be replaced immediately.


Data East general illumination power connectors, like many other game systems, tend to burn from long hours of continuous use at current levels higher than the connectors can handle. These connectors are caught in a death spiral of heat & tarnish which increases resistance, which increases current draw, which increases heat and tarnish, etc.

The only sure correction for these connectors is complete replacement of both the male and female connectors.

4.7.6 Low 5VDC and game resets

If you have a low +5v, you'll experience game resets, especially when pressing the flippers during multiball. A 'shotgun' repair would be to replace...

  • bridge rectifier (DB1, CM3501),
  • C2 (100uf 25v),
  • C3 (47uf 63V),
  • C7 (330uf 25V),
  • LM723 voltage regulator,
  • TR5 (2N6057) on the power supply board (use 2N6059 or 2N6284 to replace obsolete 2N6057),
  • C1 (1000uf 25V) can also be replaced when you have problems with the -12V supply too.

Most times, this will correct problems with the 5VDC power supply

4.7.7 PS 520-5047-01 - High Voltage Missing at the DMD display

A Small DMD display, with traces designed to use the MJE340 and MJE350 transistors. The MJE350 on the right (at TR4) has been replaced by an MJE15031, necessitating reversal of the part and heat sink.


The following sections discuss using an MJE340/350 in place of an MJE15030/1 or vice-verse. While these transistors are interchangeable, if one is used to replace the other in a board specifically designed for one type, the part must be reversed. This will necessitate reversing the heat sink also, as shown at left.

A Small DMD power supply, which uses MJE340 and MJE350 transistors at TR3 and TR4 (the parts screwed to heat sinks).


The small DMD power supply uses MJE340 and MJE350 transistors to create the high voltages. Note the lack of the larger "tab" heat sinks that the beefier MJE15030 and MJE15031 parts feature.

4.7.7.1 No +68v is found at the DMD display

Warning Be extremely careful not to touch anything when working on live High Voltage (HV) circuits.

Assuming it's not the transfomer, connectors or fuses then you should be able to measure a +DC High Voltage (HV) at the banded side of D5 with respect to GND.

If no voltage there, suspect fuses and then test D5 on the diode setting and replace D5 with a 1n4004 diode. Also test, and replace D7 with a 1n4004 diode at the same time for good measure as it's a penny part and probably stressed. Same procedure although it rectifies the a -DC HV.

Measurements are with respect to ground. You should now have a HV +DC reading at the banded side of D5. Test for +68v output. You should also have a HV -DC reading at the non-banded side of D7. Test for -100v and -98v DC output.

Do not be concerned if measured voltages are not exact without a DMD connected, they will read lower under load. It can also be that the DMD display itself is faulty and taking down the PSU.

Capacitors C10 / C11 are important, if you can't test then replace them. Especially if it looks to bulge at ends, old capacitors dry out and then fail. C10 and C11 are both 100uF @ 200v. You should be able to use 150uF at a higher voltage for these, so 150uF @250v is fine.

Observe the polarity of the capacitors you remove and mark with a Sharpie if not already indicated on PCB mask. This is very important for Electrolytic capacitors which have a polarity!

D5 / C10 are for the +68v HV DC to the DMD Display. D7 / C11 are for the -98v and -110v HV DC to the DMD Display.

The circuit for +68 voltage is comprised of components under CN5 / CN6 of the Power Board (PSU).
+68v circuit
Part Description Location Equivalent
MJE340† NPN transistor TR3 MJE15030
MPSA92 PNP transistor TR1 available
1n4760B 68v zener diode D9 available
1n5228 3.9v zener diode D6 available
1n4004 diode 400v @ 1A D5 available
47K resistor 1 Watt R8 available
330K resistor 0.5 (1/2) Watt R11 available
1.5K resistor 0.5 (1/2) Watt R12 available
500 ohm resistor 10 Watt Ceramic R15 available
100uF @200v Capacitor C10 e.g. 150uF @250v
† The MJE15030 is a heavy duty version of the MJE340 (TR3)

Check values of the above resistors. Any out of spec. (or showing open) will need to be replaced first. Test DMD again. Then replace the 1N4760 68v and 1N5228 3.9v zener diodes and test DMD again. Then work through the transistors, replacing TR1 then TR3 test the DMD.

4.7.7.2 No -100v is found at the DMD display

Follow a similar procedure to the one above. The plus and minus HV circuits are nearly 'mirror images'.

A missing -98v DC output only while reading -100v points to D11 (1n4742 12v zener diode) or R14 (4K @ 10W ceramic resistor) as faulty. Test resistor value R14 and replace if open or out of spec. Then replace D11 observing banded side for polarity.

The Circuit for -100 and -98 HV voltages are comprised of components under CN5 / CN6 of the Power Board (PSU).

-100v / -98v circuit
Part Description Location Equivalent
MJE350† PNP transistor TR4 MJE15031
MPSA42 PNP transistor TR2 available
1n5379b 110v zener diode D10 available
1n5228 3.9v zener diode D8 available
1n4004 diode 400v @ 1A D7 available
47K resistor 1 Watt R9 available
330K resistor 0.5 (1/2) Watt R10 available
1.5K resistor 0.5 (1/2) Watt R13 available
100uF @200v Capacitor C11 e.g. 150uF @250v
† The MJE15031 is a heavy duty version of the MJE350 (TR4)

Check values of the above resistors. Any out of spec. (or showing open) will need to be replaced first. Test DMD again. Then replace the 1N5379B 110v and 1N5228 3.9v zener diodes and test DMD again. Then work through the transistors, replacing TR2 then TR4, test the DMD. Get the -100v output working first, then go after the -98v circuit.

-98v circuit only
Part Description Location Equivalent
1n4742 12v zener diode D11 available
4K resistor 10 Watt Ceramic R14 available

4.8 Lamp Issues

4.8.1 General Illumination Issues

The single largest issue with general illumination lighting in Data East games, like Williams System 11 games, is burned GI connectors at the power supply. Repinning both sides of the connector is the best solution. Be sure to use "trifurcon" crimp pins in the female .156 9-pin connector housing.

 Pin 
 Wire Color at CN8    
1 (top)
 Brown
2
 Yellow (yellow)
3
 Green
4
 Violet
5
 Key
6
 White-Brown
7
 White-Yellow (yellow)
8
 White-Green
9
 White-Violet
A nicely repinned General Illumination (GI) connector on a Data East Power Supply.
This GI connection at the PPB Board shows heat stress. Both the male and female sides of this connector should be replaced.


General illumination power is sourced at the power supply board located in the upper left side of the game head. AC power comes in via a 4-pin connection at CN9. A GI relay cube on the power supply is under CPU control to switch all GI power on/off during game play. Power leaves the board at CN8, a nine pin connector (4x GI circuits plus a keying pin) and is routed through the PPB board to add fuse protection. The circuitry on the PPB board does nothing other than add fuse protection. The power enters the PPB board at J5. Each of the 4 separate GI power lanes is fused on the board. GI power then exits the PPB board through the same connector (J5).

The male connector on the PPB board (J5) is subject to cracked solder joints since the board is single sided. If you are experiencing GI issues, in addition to checking for burned connectors, wiggling J5 on the PPB board will sometimes identify the source of the problem.

A Data East Z connector. This one in the GI circuit. The only thing missing here is some marshmallows.
The burned header pins on this Data East power supply prevented some of the GI circuits from working.


Data East also used "Z connectors" instead of the more typical "cube" molex connectors. The example at left shows an extremely toasty GI connector between the backbox and the backbox lamp insert panel. Correct this by removing the connector completely. Solder each wire directly together, using heat shrink tubing to insulate. This connector facilitated cheap/fast manufacture and serves no purpose now, unless the user wants to remove the lamp board insert, which is highly unlikely.

4.8.2 Controlled Lamp Issues

4.9 Switch Issues

Data East machines have switch testing built into its diagnostics. If a switch has not been activated in a while (typically 50 games) the machine assumes the switch has failed and displays a message when powered on. Sometimes this message can appear because a working switch hasn't been activated during play. You can manually activate the switch to clear this message.

Data East uses a switch matrix to control all switches except the test button switches and the special solenoid switches. A general discussion of the switch matrix is discussed elsewhere in the PinWiki.

4.9.1 Single Switch Issues

  1. For micro-switches, make sure the switch lever still works. You should hear a faint "click" when the lever is moved and the switch is activated. You can sometimes form (bend) the switch lever to make the switch require less travel to activate a closure. Note that these switches can still be bad even when the click is audible. The best thing to do is put your machine in switch test mode and manually actuate the switch. If the game does not report the switch closure 100% correctly, replace the switch and the diode. The micro-switch (180-5064-00) on the Vertical Up Kicker (VUK) can wear out. A replacement can be sourced from DigiKey as 480-2381-ND from Honeywell Sensing (MFG PN# V7-1C17D8-048).
  2. You can use a multimeter instead of the machine's built in switch test to test the switch.
    1. Set your DMM to continuity.
    2. Place one lead on the common lug (it should have the banded end of the diode)
    3. Place the other lead on one of the other lugs.
    4. The continuity setting should change when the switch is activated.
    5. Move the DMM lead not on the common lug to the remaining lug.
    6. The continuity should change and work in the opposite manner.
    7. Note that this test only tests the switch itself, not the circuitry responsible for reacting to a switch closure nor the wiring between the switch and other components.
  3. For leaf switches, make sure the contacts are adjusted properly. You can clean the contacts with a business card by putting the card between the contacts, closing the switch, and quickly removing the card.
  4. Check the diodes for correct orientation and that they are connected correctly. Typically the banded end of the diode goes toward the lug farthest from the common lug. Check your game's manual to be sure. Diodes do fail, but rarely. 1N4001 diodes can be replaced with 1N4002 thru 1N4007 diodes.

4.9.2 Complete (or most of a) Column/Row of Switches Not Working

If a complete column or row of switches are not working, determine first if the problem is on the CPU or out on the playfield.

4.9.2.1 On Board/Off Board Switch Matrix Problem Determination

The first step in diagnosing a switch matrix problem is to determine whether the problem is on the MPU or somewhere in the game wiring.

Testing Data East MPU column drive circuitry using a logic probe.


Testing the MPU board's column drive circuitry can be done quickly with a logic probe. Connect your probe to the 5V and Ground test points at the top of the MPU. Probing through the back of the switch column connector (green wires) should result in an identical pulse with each position tested. Note that the higher columns may not be pulsed in games that don't use the full 8-by-8 switch matrix.

Testing a Data East switch matrix operation by connecting a row to a column. Note that a diode is NOT necessary for this test.


Testing the complete MPU switch matrix circuitry requires a jumper wire with a conductor on each end (or at least bare wires). This test will verify both the column and row circuitry on the MPU.

  1. Remove CN8 and CN10 from the MPU.
  2. Power the game on.
  3. Place the game in switch test.
  4. Using a short length of wire with a clip on at least one end, jumper pin 1 to pin 1, then pin 2 to pin 1, etc.
  5. Each time you jumper a pin, a single switch closure should be reported.
  6. If the game reports only a single switch closure each time you jumper two pins, your MPU is working fine.
  7. If the game reports multiple switch closures when you jumper two pins, then your MPU switch matrix has been damaged, probably by shorting high voltage to either a switch matrix row or column on the playfield. Reminder...never risk shorting high voltage to the switch matrix by working on the game with power on.


4.9.2.2 Switches Not Working Due to Playfield Wiring

If the problem is on the playfield, then it is likely that the column/row wire is broken or the connector is at fault. Following are several techniques you can use to find the fault.

  1. If a complete row/column is out, then either the female connector is bad, or the wire is broken prior to the first switch as physically wired in the game. Note that "physical" wiring order will almost certainly differ from the schematics.
  2. If something less than a complete row/column is out, then a wire is broken between two of the switches. Track the wire color from one switch to another or use your DMM to "buzz" between switch solder lugs of two switches. This can help you narrow the search.

4.9.3 Multiple Switches Reported from a Single Switch Closure

A ball trough switch bent and shorting column and row wires together. The insulator has also slipped off of the green/red wire lug. This caused multiple switch closures to be reported when only a single switch was closed.



If pressing a single switch in switch test causes the game to report multiple switch closures, determine first if the problem is on the CPU or out on the playfield.

If the problem is on the playfield, inspect the likely switches to ensure that none are shorted to themselves. Check to make sure that the leads do not touch or have not been bent together and that the diode is not shorted against the common lead, as shown in the picture at left.

4.9.4 Periodic "Random" Slam Tilts

A real hair puller. This screw is making contact with the switch lug, resulting in "slam tilts".



Thanks to a couple of folks on RGP for posting this one and to Cliffy for the picture.

Games with playfield hangers and elevated ball troughs (ball trough is located above the playfield) similar to Star Wars, Lethal Weapon 3, Hook, etc. may "slam tilt" unexpectedly. The cause of this is a playfield hanger screw that backs out, makes contact with the lower switch lug, and completes the path to ground for the switch. This causes a "sneak circuit path" in the switch matrix and results in slam tilts as well as other switch anomalies.

4.10 Score Display Issues

Early Data East pinball machines used alpha-numeric score displays similar to those in Bally/Williams Machines. Data East was the first pinball manufacturer to use a dot matrix display (DMD) in a pinball machine, and had three different generations of the display. Starting with Checkpoint and running through Hook, Data East used a 128x16 score display. Williams first used the common 128x32 display in Terminator 2, and Data East soon switched to this display size for the majority of their machines, (from Lethal Weapon 3 until Guns N' Roses). Data East then switched to the larger 128x64 display. This display was used in only four Data East / Sega games including: Maverick, Frankenstein, Baywatch, and Batman Forever.

4.10.1 Outgassing Displays

An "outgassed" display on a Williams FishTales during display test (all pixels should be on except the single vertical line). This display took several minutes to "warm up". The plasma seemed to "float" with various portions at the top of the display appearing dark.


DMDs will eventually fail. It is important to replace an outgassing display as they place extra strain on the power supply, and will eventually damage the power supply.One sign of an outgassing display is that areas of the display need to 'warm up' before becoming fully bright or that the display will remain completely blank for a few seconds and then appear normal.

4.10.2 Display is "delayed" after turn on

There are cases of import machines incorporating an aftermarket circuit that delays the DMD display from appearing for a fixed amount of time after the game is booted. This was done by some operators so that serial number and location information could not be seen when the machine is powered on, thereby preventing identification of a game, and potential sales/operation outside a given geographic area. This circuit will not damage anything but is not standard. More information about this can be found in a rec.games.pinball discussion.

4.10.3 Alphanumeric Issues

Data East 520-5030-00 Alpha-Numeric 16 digit display


The Data East #520-5030-00 Alpha-Numeric score display board uses two 16 digit alphanumeric display glasses.
This display was used in:

  • ABC Monday Night Football
  • RoboCop
  • Phantom of the Opera
  • Back To The Future
  • The Simpsons


Due to many inquiries to the factory from field technicians, Sega/Data East issued a service bulletin which explained the operation of alpha-numeric displays (bulletin 87), which can be found at the following link.

Service Bulletin 87 describing alpha-numeric displays

The Data East segment identification scheme, which is identical to the Williams method.


Connector CN1 is the segment select for the lower score display glass. This connector handles the a, b, c, d, e, f, g, and comma segments. ICs at U1 (CD4050), U5 (CD4050), U16 (UDN7180 operating on -100v), and U17 (UDN7180 operating on -100v) as well as resistors R1 through R8 (18k, 1/2 watt) all handle this portion of the circuit.

Connector CN2 is the digit select for digits D1, D2, D3, D4, D5, D6, D7, and D8. The circuitry handling this function consists of resistors R9 through R16 (18k, 1/2 watt), ICs U4 (CD4001), U3 (CD4001), U15 (UDN6118 for the lower display, operating at +90v), and U11 (UDN6118 for the upper display, operating at +90v).

Connector CN3 is the digit select for digits D9, D10, D11, D12, D13, D14, D15, and D16. The circuitry handling this function consists of resistors R17 through R24 (18k, 1/2 watt), ICs U9 (CD4001), U10 (CD4001), U18 (UDN6118 for the lower display, operating at +90v), and U14 (UDN6118 for the upper display, operating at +90v).

Connector CN5 (ribbon cable) provides the remaining segment selects for both displays. This controls segments h, j, k, m, n, p, r, and dot (lower display only) and a, b, c, d, e, f, g, h, j, k, m, n, p, r, dot, and comma (upper display only). The circuitry handling this function consists of resistors R25 through R32 (18k, 1/2 watt for lower display only), ICs U2 (CD4050), U1 (CD4050), U5 (CD4050) for the lower display, U16 (UDN7180 operating on -100 volts), U17 (UDN7180 operating on -100 volts) for the lower display, U6 (CD4050), U7 (CD4050), U8 (CD4050) for the upper display, U12 (UDN7180 operating on -100 volts), and U13 (UDN7180 operating on -100 volts) for the upper display.

Connector CN4 provides power. Note: Zener diode D1 (type 1N4740) on the board regulates the +100 volts down to +90 volts.

  • Pin 1: -100 volts
  • Pin 2: No connection
  • Pin 3: +100 volts
  • Pin 4: Key
  • Pin 5: Ground
  • Pin 6: +5 volts

The 16 digit alpha-numeric display glass is becoming very expensive. If you feel it is too costly to repair your original Data East display board, Rottendog, XPin, and maybe others manufacture very nice LED replacement displays. These are directly plug n play compatible with the original board plus it no longer needs the high voltage +100/-100 any more.

4.10.4 Dot Matrix Issues

Although Data East board designs share many similarities between Bally/Williams, the score display CPU is implemented very differently. Data East has a separate board and CPU for controlling the dot matrix display (DMD). This board is mounted behind the DMD on the score panel. The main CPU and this daughterboard communicate through a ribbon cable. Because of this, it is important that your CPU and display roms are the same version, or are in sync with each other. Running different ROM versions can cause some strange display issues. Ribbon cables are known to have faults, so reseating or swapping the cable may fix some issues.

4.10.4.1 128x16 (Small DMD) issues

The 128x16 DMD was the first DMD used in a pinball machine and was used for five games. It was replaced by the much more familiar 128x32 display.

Sometimes this display will light but the display will appear garbled. The display will flicker and move but the output will not be readable. This can be caused by the R95 resistor on the DMD controller board going out of spec. It should be a 33k 1/2 watt resistor.

4.10.4.2 128x32 (Regular DMD) Issues

The 128x32 DMD was used in the majority of Data East machines and was the only size used by Bally/Williams. The display glass is the exact same version for both Data East and Bally/Williams and can be used as a drop in replacement. However, you will still need the DMD controller board used by Data East machines.

Before and after shots of the display board after upgrading from the stock board with two 2MB ROMs. Notice the removal of the 0 ohm resistor(jumper) at R11


Some games such as Lethal Weapon 3 and Star Wars sometimes used two 27020 EPROMs at locations U12 and U14. You can use one EPROM instead if upgrading to newer code. If one EPROM is used, R11 should be open (nothing installed). This part can simply be cut off the board. If two EPROMs are used, R11 should be jumpered with a zero ohm resistor or a jumper wire. Why Data East called this a resistor (R11) vice a jumper, is anyone's guess. This is discussed in service bulletin 38B.

It is worth mentioning that if two 2MB EPROMs are used, and the R11 zero ohm jumper is not installed, the DMD will remain blank.

High voltage for the DMD is located on the PSU board.

Connection CN2 on the DMD controller board can sometimes be problematic. This is a three pin connector, and only two of the header pins are used for the +5vdc and ground. It is always a good practice to upgrade the connector pins in this housing to Trifurcon connectors. Using Trifurcon connector pins will help ensure that a more solid connection is made at CN2. Unfortunately, the existing connector housing is not reusable, and will have to be replaced when the connector pins are upgraded.

4.10.4.3 128x64 (Large DMD) Issues

The large 128x64 DMD was used in the last four Data East pinball machines. The display is a relatively expensive part to replace, costing several times as much as the more standard 128x32 DMD.

One of the most common issues with this display is that it will periodically go blank or reset the CPU. These issues are typically due to the logic power needed to drive the DMD controller board chips dropping below the required +5vdc. As Stern mentions in their service bulletin, the controller board runs at +5vdc, and "'likes' its 5 volts or darn near close". To overcome the issue, Stern offers an optional wiring harness to increase the reliability of the +5vdc logic power by pulling the +5vdc from an otherwise unpopulated connector on the power supply. A detailed discussion of the kit can be found in service bulletin 106.]

4.11 Solenoid Issues

4.11.1 Driver Transistor "Quick Check"

You can quickly test the TIP102/TIP122 transistors (Q8-Q13, Q23-Q30, Q39-Q46, Q72-Q79) on the MPU by...

  • Turn the game OFF
  • Set your DMM to Ohms/Continuity buzz
  • Attach the black lead to one of the metal grounding straps (crocodile clips are helpful here), there should be one in the backbox you can use
  • Touch the red lead to the metal tabs of the TIP122/TIP102's
  • Any continuity indicates a shorted transistor that should be replaced. Should the game be powered on, the associated coil, flasher, motor, etc will be turned on.

You may also need to replace the pre-driver transistor (2n4401) that the failed transistor is connected to. It is also wise to check the wiring and the coil before powering back on, otherwise you may blow the transistor you just replaced.

See Testing a coil

4.11.2 Flipper Issues

Flipper Coil using the earliest "Deger" design (Monday Night Football)



Data East was the first company to use solid state flippers. Starting with Playboy 35 Anniversary, Data East flippers began using a single wound coil instead of the high/low windings found in earlier games and Bally/Williams games. This single wound flipper coil design was developed by Kurt Deger, and is commonly referred to as the Deger design. Although it has gone through some transformation over the years, it is found in most of the Data East games. Service Bulletin #62 contains a listing of flipper coil parts for Data East games and shows the evolution.

The patent for the original Deger design can be viewed here.

When a Data East flipper is energized, 50 volts is sent to the coil for the initial flip. The FFASI board then drops the voltage to 9 volts so that the flipper may be held up for a long period of time without burning the coil. This voltage drop occurs after 40 milliseconds, is CPU controlled, and cannot be adjusted. This is similar to the Bally/Williams WPC FlipTronics II design where the flipper hold is controlled by the FlipTronics II board. Still, many note a different feel between Data East and Bally/Williams flippers.

Data East eventually did add an EOS switch to its flipper design beginning with Jurassic Park. This does differ from Bally/Williams in that the switch is normally closed in Data East games. This was done because certain game features fired the ball quickly back to the flippers. If the ball hit the flippers and moved them 1/16 of a inch the EOS switch would open and 50 volts would again be delivered to the flipper. This is discussed along with the general theory of Data East flipper operation in Service Bulletin #49. With this design if the hold voltage is broken and the EOS is badly adjusted, you may experience 'machine gun flippers'.

4.11.2.1 Solid State Flipper Board Issues

These flippers are controlled by the solid state flipper board (TY-FFASI board) which is mounted in the cabinet. The board is prone to a few failures, but it's a fairly simple circuit so fixing it is normally quite easy. You should see a red LED illuminate briefly when the flipper buttons are pressed.

To test the flipper board:

  • Remove the board from the cabinet (it's much easier to work on)
  • Check all the fuses on the board, 4 in total (2 power, 2 hold). Also check the fuse clips.
  • Check all transistors using a DMM
  • Check tracks for continuity and corrosion
  • Replace board back into cabinet and power on game
  • Enter Diagnostics (so power is sent to the flippers)
  • Check for 50VDC at the coil lugs (DMM set to DC volts, black lead on game ground, red lead on banded side of coil diode)
  • Press flipper button and check for about 8VDC hold voltage
  • Check power/hold voltage on flipper board (DMM set to DC volts, black lead on game ground, red lead on CN2 pins 6&7 (8VDC hold), CN2 pins 8&9 (50VDC power stroke)

If you have no voltage on CN2-8 and CN2-9, check the PPB board J7-1 and J7-5.

If you have no hold voltage on CN2-6 of the flipper board, check the Power Supply board CN1-10 and CN1-11. If you have no hold voltage on the coil lugs, check the hold fuses on the TY-FFASI board.

  • The newer 520-5080-00 (EOS) flipper board can be modified to work in games requiring the 520-5033-00 (non-EOS) flipper board. Steps to do this can be found in Service Bulletin #103.]
4.11.2.2 Pathetically Weak Flippers

One cause of very week flippers in games that use the solid state flipper board, is lack of good ground for the flipper cabinet switches.

A ground connection is daisy-chained through the flipper cabinet switches. This ground then proceeds to the solid state flipper board (where an IDC connector is used...something to investigate), and then onto the general game ground. Without a solid ground for the flipper cabinet switches, a weak power pulse may be all that is delivered to the flipper coils.

The fuse clips on many Data East boards are often weak and may snap if bent closer together. The fuse clips must mechanically hold the fuse very tightly, allowing maximum electrical current to pass. Replacing weak fuse clips is mandatory for improved game performance.

4.11.2.3 Flipper Repair and Rebuilding
Composite of a Data East Flipper Plunger and Link. Note how "hogged out" the large hole in the link is in the top image. The middle image shows the "slop" with the plunger pushed in. The bottom image shows the "slop" with the plunger pulled out. All three images are the same flipper plunger and link.


A major contributor to weak flippers in any game, including Data East, is a damaged or "hogged out" flipper link. The picture at left shows a flipper link with about 1/8" of "slop" in it. When the flipper coil pulls the plunger in, the flipper crank doesn't begin to actuate the flipper until all of the slack caused by this slop is taken in. At the very least, replacing the link is warranted.

Flippers at the hold position before a rebuild
Data East Flipper Rebuild Parts - Return Spring, Plunger/Link Assembly, Coil Spring, EOS Switch, Coil Sleeve, Flipper Bushing, Coil Stop, Spring Washer


A flipper rebuild is one of the easier things you can do to improve the playability of your machine. Over time the parts of a flipper will wear and need replacing. Signs of this include weak or slow flippers, flippers that do not return quickly, or flippers that travel too far. An experienced repairman can just replace the needed parts but it is far easier to buy a flipper rebuild kit from a pinball supplier. These kits will contains all the parts needed for a general flipper rebuild. Flipper coils are not included in rebuild kits but are not typically needed for a repair.

Some parts are interchangeable between Data East and Bally/Williams flippers due to the similarities in design. For example, coil sleeves, links, and plungers are the same. However the flipper bushings and coil stops, although appearing similar, are not compatible. Buying a complete flipper rebuild kit for your machine will ensure you get all the correct parts.

Used and new coil stops. Excessive wear has caused the coil stop to mushroom and allow the flipper to travel too far
Aligning flippers on a Data East machine


Below are the steps to rebuild an early Data East solid state flipper. This guide does not currently address the additional steps needed for replacing or adjusting EOS switches.

  1. Remove the coil stop.
  2. Pull the coil away from the flipper assembly. Typically the coil does not have to be replaced, so desoldering the leads is not necessary. Remove the plastic coil sleeve from the coil. This should slide out somewhat easily, but a nut driver can be used to push it out. If you cannot remove the sleeve it may have warped due to heat issues. If this is the case, replace the coil. Always replace coil sleeves when rebuilding flippers.
  3. Remove the return spring.
  4. Loosen the allen screw that holds the flipper shaft in place. The flipper can now be removed from the top of the playfield. Remove the plunger and link assembly.
  5. Replace the rubber stopper where the link assembly rests.
  6. Clean the metal parts of the flipper assembly.
  7. If your existing flipper has one, remove the spring holder and put in on the new link assembly. Attach one side of the new return spring to the spring holder.
  8. Replace the flipper from the top of the playfield.
  9. Loosen the flipper bolt and replace the plunger/link assembly. Do not tighten this yet.
  10. Attach the other end of the return spring.
  11. Assemble the coil. Be sure to put the end with the lugs away from the coil stop.
  12. Replace the coil stop and the spring washer.
  13. Adjust the flippers from the top of the playfield. On Data East machines the guide holes align with the tip of the flippers. Tighten the allen screw on the link assembly to hold the flipper shaft in place.


A Williams plunger/link/crank assembly and EOS switch, installed on a Data East Tales from the Crypt.


As mentioned above, some Williams flipper parts can work in Data East games. In the picture at left, a Williams plunger/link/crank assembly and EOS switch have been substituted. To make this work, the EOS "finger" on the crank must be bent straight and the EOS switch position must be adjusted. It works surprisingly well. The feel is very solid.

Upper Right Flipper on a Data East game (Jurassic Park)


It is worth noting that Data East games which use a solid state flipper board, and have upper flippers, do not use EOS switches on these flippers. If an upper flipper appears to be missing the EOS switch, it actually is not. This is an intended design.

4.11.3 Ball Trough Issues

Typical Ball Trough on Later Data East Games


Starting with Jurassic Park, a different type of ball trough is used. This ball trough is mounted below the plane of the playfield versus the old style, which is mounted above the playfield. The main purpose of this trough is to allow the storage of more pinballs in the trough. However, there are a whole new list of potential problems that come along with this design.

Lock Ball Assy. used on Later Data East Games Where sublevel ball trough is used


Data East / Sega Ball Trough with Ball Divots (Jurassic Park)


Sega Baywatch ball trough opto


When the VUK at the end of the ball trough pops over and over, the game thinks there is a ball in the end position, and is trying repeatedly to clear it. It's possible that the opto is not aligned properly, or that the solder joints at the connector have failed or are cracked. It is also possible that the solder joints for one or more SMD components on the opto board have fractured, which are very difficult to see, even under strong magnification. Reflowing the solder points can sometimes solve this problem. If reflowing the solder joints does not resolve the issue, replacement of the opto pair is recommended. When replacing the ultra brite red LEDs, replace both the transmitter and receiver, These can be acquired from GPE under part # MV8114.

4.11.4 Flasher Issues

Data East games usually have 4 flash lamps wired in parallel off an individual coil driver circuit. It is critical that all 4 (or at least 3) flash lamps are working on each circuit, otherwise you run the risk of all of the bulbs on that circuit burning out quickly due to the increased load each working bulb has to bear. Frequently, you will pick up a Data East game where many of the flash lamps are burned out. A common mistake when checking and replacing flash lamps on these games is to replace a single burned out flash lamp, only to find out when testing it, that it will light once and burn out, because it was the only working flash lamp on that circuit. The solution is to check the manual for the location of all the flash lamps in that circuit and make sure at least two flash lamps (but preferably 3) on the circuit are working before testing.

4.12 Sound Issues

The Data East Sound board architecture closely resembles that of the later Sega / Stern Whitestar CPU / Sound board.

4.12.1 Boot Sound Clipped

Each Data East game will play a short sound clip when the sound board boots. On some titles, and maybe all titles, this sound is "clipped", or cut off. This is entirely normal and does not indicate a problem.

4.12.2 Missing or Broken Pins on the MPU-to-Sound Connector

Pin 19 header pin missing from the Sound Board Interface connector.


It is fairly common for the MPU board to have pin 19 missing from connection CN21. This is the ribbon cable connection between the MPU and the sound board. While this seems odd, it's not actually a problem, because the "E" signal carried on this pin is not used by the sound board.

5 Game Specific Problems and Fixes

Please see the game specific pages for some game specific problems.

5.1 Star Trek 25th Anniversary Edition blown switch matrix

The subject flashlamp, clearly touching this switch solder tab.


The picture at left shows the flash lamp that is under the center shot to the subway, under the dilithium crystal "toy". In the picture, you can see that the flasher is touching one of the switch solder tabs. Not surprisingly, the switch matrix column driver for the green/orange column (switch drive 3) was blown. Luckily, the damage extended only back to the 2N3904 at Q53. Wrapping the flashlamp socket, or the switch solder tabs with a bit of electrical tape is a reasonable solution to prevent this potentially serious issue.

6 Repair Logs

CPU Board Repair
Data East Power Supply Rebuild

6.1 Delayed or Missing Blanking Signal

Time Machine CPU board - blanking signal would go high approximately after 7 seconds or more, (if it went high at all), after PIA diagnostic signal would go low (PIA LED would go out). For a properly functioning CPU board, the blanking signal should go high immediately after the PIA signal changes its state from high to low.

Resolution: a bad AMI 6808 CPU chip. Beware of failing AMI chips. It is rumored that AMI chips have higher failure rates than most other manufacturers. This ultimately was a simple fix, but after extensive troubleshooting was performed first. This particular fix is more of an exception than the rule. Generally, a missing blanking signal should be isolated to the blanking generator circuitry (555 timer chip, 2N4403, etc.).

6.2 Incorrect Flipper Pawl Screw Installed

Jurassic Park, but applies to other games

Data East Flippers with Extra Long Screws Used on Flipper Pawls

This falls under the "not too often category", but it is worth mentioning. The screws used to tighten the flipper pawls have a dual duty. They of course secure the flipper pawls to the flipper bat, but they also open the flipper EOS switch.

There were two problems with flippers on this game, as can be seen in the pic on the left. First, the screws used were Phillips head screws. A Phillips head screw does not allow for enough torque to adequately secure the flipper pawl to the flipper bat shaft. The factory screws used are #10-32 x 3/4" hardened steel socket head hex Allen screws. In using an Allen screw, chances of stripping the head are minimized, and much more torque can be applied when tightening. The second problem was that the replacement flipper pawl screws were too long. By using a longer screw, it messes with the solid state flipper board's timing, because the EOS switch is opened prematurely. The end result was a weak spastic flipper.

Resolution: Installed the proper #10-32 x 3/4" hardened steel socket head hex Allen screw on both flipper assys.

6.3 Broken/Missing Backbox Latches

Monday Night Football, but also applies to other early Data East cabinets. Machine came in with completely missing backbox latches. The Data East backbox latches are very flimsy and easily stripped out of the wood.

Resolution: Use Williams parts instead. Use # 20-9347 Toggle Latch and # 01-8397 Toggle Bracket. They are wider and beefier which provide better securing of the backbox.