Sega/Stern White Star Repair
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1 Introduction
2 Games
2.1 Sega
- Apollo 13
- Goldeneye
- Twister
- Independence Day
- Space Jam
- Star Wars Trilogy
- The Lost World Jurassic Park
- The X Files
- Starship Troopers
- Viper Night Driving
- Lost in Space
- Godzilla
- Harley-Davidson
- South Park
2.2 Stern
- Striker Xtreme
- Sharkey's Shootout
- High Roller Casino
- Austin Powers
- Monopoly
- NFL
- Playboy
- Roller Coaster Tycoon
- The Simpsons Pinball Party
- Terminator 3: Rise Of The Machines
- The Lord Of The Rings
- Ripley's Believe It Or Not
- Elvis
- Grand Prix
- The Sopranos
- NASCAR
3 Technical Info
3.1 The White Star Board Set
3.1.1 CPU / Sound Board
- The two generations of the Sega/Stern WhiteStar MPU
Stern White Star CPU/Sound Board 520-5136-16 (Monopoly) 
Stern White Star (modified) CPU/Sound Board 520-5300-00 (LOTR and forward). U201, U213, and U413 are socketed on this board as a result of alkaline damage abatement.
There are two versions of the White Star CPU/Sound board. The board as used in Sega machines starting at Apollo 13 (A13) and Stern machines up to Terminator 3 (T3) are the standard version as shown above which is part #520-5136-16. Stern machines starting from Lord of the Rings (LOTR) used a different version of the White star CPU/Sound board called White Star modified, part #520-5300-00. Stern had this in-between version made because the BSMT2000 audio chip wasn't available anymore and having it reproduced was too expensive. The White Star modified therefore uses an BSMT2000 emulation circuit consisting of an Atmel AT91R40008 microcontroller and an Atmel AT49BV1614 16Mbit flash memory.
Note: Stern states that the board is backwards compatible with the standard version so it can be used in Sega White Star based games and White Star based games from Stern prior to LOTR as well. However, some sounds may not render correctly when using the Atmel based board with prior game software (StarShip Troopers for instance).
The BSMT2000 based White Star sound system is basically the same as the sound circuitry on Data East/Sega soundboards 5020-5050-0x, 5020-5077-00 and 5020-5126-02.
There are some programmed TIBPAL16L8 PAL chips on the board. These are programmable logic chips. They have a colored dot on them so they can be distinguished. U213 is one of these chips and it's right in the battery corrosion area. It is readily available, already programmed under part number 965-6504-00 (blue dot), the only exceptions to that are Sharkey's shootout using part number 965-5023-00 (gold dot) and Lord of the Rings LE with a shaker motor installed using a different part number (the standard LOTR without a shaker motor uses the standard 965-6504-00 but the software version supporting the shaker motor will only run on the alternative U213).
There are two more PAL chips on the board at U19 (yellow dot, 965-0136-00) and U20 (white dot, 965-0137-00). These aren't needed very often for repairing sound boards but they do go bad now and then. Data retention for these programmable logic chips is generally specified at 20 years or more. The first Whitestar boards are from 1995 so from 2015 they start exceeding the data retention period and although big problems are not to be expected it wouldn't be unlikely when more of these start to fail.
The programmable logic in the board design makes it harder to repair the boards because of the grey area it causes in the schematics as there aren't any logic diagrams of these available. In short; you don't know what they do so you don't know what the output should be.
"Blink Codes" do not exist for the 68B09E or the Atmel based MPU. With one exception (Atmel based board) anything blinking is a side-effect of improper board operation. The blinking may help you diagnose the actual board problem, but blinking LEDs are not driven with intent by the processors. i.e. There are no "Bally -17-like Blink Codes".
The single exception to this is LED1 on the Atmel based MPU. LED1 on this board will blink anywhere from 5 to 8 times to indicate the sound operating system version contained in the flash memory at U8. Stern has provided a good explanation within service bulletin 157. This service bulletin also describes the process to update flash memory to a newer version of the sound operating system (which is not recommended unless you encounter sound issues after moving an MPU from one game to another).
There are two JTAG (Joint Test Action Group) connectors available on the Atmel based board. One connects to the Xilinx CPLD (Complex Programmable Logic Device). The other connects to the Atmel R40008 processor. The JTAG interfaces to this board and their use have not been documented publicly.
Schematics for the 520-5136-16 board are available here from Stern's website.
Schematics for the 520-5300-00 board are available here from Stern's website.
3.1.2 Power Driver Board
Power, fuses, bridge rectifiers. GI relay, coil and flasher drivers.
++ Need pic of the Sharkey's Shootout (Tournament Ed.) driver board inserted here +++
Schematics for the 520-5137-01 board are available here from Stern's website.
Schematics for the 520-5137-64 board (Sharkey's Shootout Tournament Edition only) are available here from stern's website.
Schematics for the 520-5137-01 board (100 ohm resistors added on J2 aux. port lines) are available here from stern's website.
High current coils (50vdc) 1-8 (group 1) and 9-16 (group 2). Q15 and Q16 typically drive the left and right flippers respectively.
Low current coils (20vdc) 17-24 (group 1) and 25-32 (group 2).
3.1.3 Display Controller Board
Schematics for the 520-5055-00 DMD controller board (through hole components) are available here on Stern's website.
Schematics for the 237-0255-00 DMD controller board (primarily surface mount components) are available here on Stern's website.
3.1.4 Display Power Supply
The output voltages of this board should be approximately: Measured from GND on CN2 pin 4/5
-110V on CN2-1
-98V on CN2-2
+5V on CN2-6 (directly from the input on CN1-7)
+12V on CN2-7 (+20V comes from CN1-6 and is regulated on +12V by VR1 (L7812CV)
+68V on CN2-8
Fuse type on the board: 0.75A SB
Common failures:
Fuse blowing
-110V missing or too low
-98V missing or too low
+68V missing or too low
Solutions:
A blowing fuse is often caused by a defect rectifier diode D1 or D2 (1N4004, can be replaced by 1N4007). When D1 was defect and replaced there's a big chance that Q1 and Q3 are defect as well. When D2 was defect and replaced often Q2, Q4 and Q5 are defect too.
-120V problems are often caused by a defect transistor on Q2 (MPSA42) and/or Q4 (MJE15031) when one of the transistors is defect there's a big chance the other is defect as well. Replace zener diode D4 (3.9V), D6 (100V) and D7 (13V) as well.
-100V problems are often caused by a defect transistor on Q5 (MJE15030) or zener diode D6 (100V), it's best to replace both. The 2k/5W resistor on R8 might also cause the problem, mostly because of bad solder contacts.
+60V problems are often caused by a defect transistor on Q3 (MJE15030) and/or Q1 (MPSA92) when one of the transistors is defect there's a big chance the other is defect as well. Replace zener diode D3 (3.9V) and D5 (68V) as well.
Schematics for the display power supply board are available here from Stern's website.
3.1.5 128 x 32 Dot Matrix Display
All Sega or Stern White Star games make use of a 128 x 32 "standard" dot matrix display.
3.2 Recommended Documentation
As always, it is highly recommended to possess a game manual. Every game manual is full of detailed information regarding game specific switch, lamp, and coil assignments. Equally, details for maneuvering through test, audit, and bookkeeping screen menus, schematics for all boards used, and game specific mechanical assemblies are included. Hard copy game manuals can be purchased through several of the recommended pinball parts suppliers. Some White Game manuals are available in PDF form on the Stern Pinball website here.
The Stern Pinball website currently archives theory of operation and board schematics in PDF format at the time of this writing. Scroll down to the bottom of this page to review the documents available.
Likewise, Stern Pinball keeps an online archive of service bulletins for Sega and Stern. The service bulletins have some great material, and are available here.
3.3 The Wire Coloring Code
White Star games do not use color coding system. Instead, the wire color was marked accordingly in the associated documentation, (ie. a green wire with a brown trace is referred to as GRN-BRN, orange with violet is ORG-VIO, white is just WHT, etc.).
3.4 Switch Matrix
3.5 Dedicated Switches
3.6 Lamp Matrix
3.7 Trough Opto Boards
++++ Need pics of the single opto transmitter and receiver boards ++++++
All White Star Games use trough opto boards at the location of the trough VUK which feeds the ball to the shooter lane. Earlier White Star games, (Apollo 13 to Godzilla - need Godzilla confirmed) use only a single opto above the VUK plunger. Later White Star games (Harley-Davidson to NASCAR / Grand Prix) use a two opto system. The lower opto serves a dual purpose. It is the opto just above the VUK plunger like earlier games, but is also designated as trough switch #4. The upper opto is designated as the "stacking opto". Its purpose is to identify when a ball inadvertently gets "stacked" above a ball located at the VUK plunger.
To briefly summarize the operation of White Star VUK opto boards, if an object is blocking the light beam between the transmitter opto LED and the receiver opto LED, the CPU detects this as a switch closure. When an object is not present to break the light beam, the CPU detects this as an open switch. The components used on the opto receiver board are designed to do as such.
The transmitter side is simply an ultra-red LED with a current limiting resistor. The receiving opto is the same style ultra-red LED, and is able to detect the light wavelength emitted from the transmitting LED. By using discrete components on the receiving side, the appropriate signal is sent to the CPU via the switch matrix return (row). When LEDs are paired together in this type of fashion, the receiving LED emits a very small amount of voltage, when the proper light wavelength is present. By employing such a design, failure on the receiver opto side is more common.
This particular system is contrary to how Bally / Williams WPC CPUs handle opto pairs. Equally, WPC games employ infrared (IR) opto switch pairs. If interested in learning the theory of operations for the White Star opto trough upkicker boards, please consult the manual. Sega / Stern have included some excellent, detailed, technical documentation within their manuals.
Schematics and troubleshooting info for the trough upkicker dual opto boards are available here from Stern's website.
Once significant source of trouble with these trough boards is fractured header solder joints.
3.8 Magnet Processor Board
Only two Sega games used this style of magnet processor board - Twister and Goldeneye. The only difference between the board used on each game is the different custom PIC / GAL chip used at position U1 on the board. When U1 for Twister is installed in the board, the board's part number is 520-5143-01. The part number for the board when U1 is written for Goldeneye is 520-5143-02.
3.9 Flippers
All Sega / Stern White Star flipper assemblies are solid state controlled. Apollo 13 and Goldeneye are the only two White Star games which use a separate solid state flipper control board located in the game's lower cabinet. Starting with Twister, the flipper board was abandoned, and circuitry to control the flippers was incorporated into the power driver board.
Please note that the adjacent pic of the White Star flipper assembly has a Williams flipper link / plunger and coil stop installed.
3.10 Accessing Bookkeeping, Settings, and Diagnostic Modes
Solid state pinball machines typically have a built in system for audits and adjustments. All White Star based machines use a system called "Portals". The Portals interface is a carry over from the last two Sega games (Baywatch and Batman Forever) which used the Data East board set.
3.10.1 Portals
The Portals system has a very user friendly, simple navigation system. Unlike previous Data East / Sega games, having to scroll through all of the audits and adjustments is a thing of the past. Diagnostic testing (including game specific assembly tests), audits, and adjustments can all be quickly accessed via the initial display menu graphical interface. The 3-button control panel (in most cases, except some earlier White Star games) used to access Portals is located on the coin door.
3.10.1.1 Setting Free Play
3.11 Coin Door Switches
Most White Star games have two switches located on a bracket inside the coin door (hinge side). The upper switch is the memory protect switch. This switch is used so that nothing can be written to the memory, unless the coin door is open. The memory protect switch is not part of the switch matrix, nor is it one of the dedicated switches. Although it does connect to the CPU / Sound board via the same connector as the dedicated switches, its state is processed by a different chip (U213) versus the dedicated switches (U206).
The lower switch is an interlock style "kill" switch. This kill switch is used to kill all power to the solenoids, when the coin door is opened. Since it is an interlock style switch, it can either be depressed (when the coin door is closed), or it can be extended outward to turn the switch on. To extend the switch to the on position when the coin door is open, grasp the switch, and gently pull it out to the lock position.
4 Problems and Solutions
4.1 Power Problems
4.2 MPU boot issues
4.2.1 Relocating the battery from the MPU board
4.2.2 Repairing Alkaline Corrosion
Sega/Stern White Star boards are well known for issues with leaky batteries. This is because the Batteries are mounted on the top of the board - with plenty of board beneath it for the corrosion to affect.
Remember - Battery Acid is an Alkali - it needs to be neutralised before fixing any damage that was caused. Most commonly used is vinegar, since it is an acid, however not a strong one and one that will adversely affect the surrounding areas of the board.
4.2.3 Connecting a logic probe to the MPU
4.2.4 Using a PC Power Supply For Bench Testing
4.3 Low +5VDC and Game Resets
The +5VDC for logic power is sourced from the 8VAC secondary windings on the transformer. The 8VAC is fed to the I/O Power Driver Board, and rectified via bridge rectifier, BRDG21. The rectified DC voltage is regulated via an LM338K adjustable voltage regulator. Logic voltage can be adjusted via R116 on the driver board, which is a 50 ohm adjustment potentiometer.
U413, which is located on the CPU / sound board next to the reset button, is a Dallas Maxim DS1232 monitoring chip. In theory, should the logic voltage dip to less than 5% or +4.75VDC, the DS1232 will force a reset of the CPU. However, it has been determined that most White Star board sets will not function properly below +4.85VDC.
If the voltage on the power I/O driver board is below the +4.85VDC threshold, adjustment can be made via the R116 adjustment pot, until a satisfactory voltage is achieved. The best location to measure the +5VDC is at the bottom leg of resistor R114. R114 is located in the vicinity of the R116 adjustment pot, and just below the +5VDC LED, L2. If a satisfactory voltage cannot be achieved, turn the game off. Remove connector J16, located above the LM338 regulator. Turn the game back on, and measure the +5V again. If a satisfactory voltage can be acquired with J16 disconnected, a board or component which uses the +5VDC is "dragging" it down. Turn the game off, and remove all 5V input connectors on all other boards at this time. Reconnect J16 again, and review the logic voltage on the I/O Power Driver board. Repeat the process of turning off the game, and reinstalling logic power connectors one at a time to determine the suspect board. Keep in mind that all opto switch receivers used throughout the game use the same +5VDC logic lines. If no other boards in the backbox appear to be suspect, an opto transmitter board may be at fault.
Should the game start randomly resetting, the first course of action is to measure the +5VDC on the I/O Power Driver Board. If the logic voltage is within spec., measure the +5VDC on the CPU / sound board. The +5V test point on the CPU / sound board is located just to the left of the 6809EP CPU chip (U209) on the board. If the voltage drastically differs between the measurement of the I/O Power Driver Board and the CPU / sound board, turn the game off. Remove and reseat connections CN2 on the CPU / sound board and J16 on the I/O power driver board.
4.3.1 Game Resets with DMD Controller Board Connected
This may be a bit of an anomaly, but it is worth mentioning. If when the DMD controller board is connected without the data line ribbon cables, and the game continues to reset, replacement of BRDG21 may be required.
In one particular instance, a game was resetting continually with only the +5v / ground connection connected to the DMD controller board. If the board was not connected, the driver board would output ~+5VDC. If the DMD controller board was connected, the driver board's logic line would dip down to around +4.85VDC. Logically speaking, this type of symptom somewhat points to the DMD controller board having issue. However, the end result was replacement of BRDG21 per Stern tech support.
It is worth mentioning that the bridge rectifier did test correctly (using a DMM in diode test) both in circuit and out of circuit, but these tests were conducted while the bridge was not under load.
4.4 Solenoid problems
4.5 Flasher problems
More regarding flashers to be added later...
Starship Troopers, and perhaps other Whitestar games, drives 4 flash lamps via a single TIP-122 transistor. As the transistor ages, it can fail in such a way that when all 4 flash lamps are in circuit, each flashes weakly. Removing one of the flash lamps from it's socket will result in the remaining 3 flash lamps flashing with normal brightness. Replace the failing TIP-122 with a TIP-102.
4.6 Lamp problems
4.7 Switch problems
4.7.1 Playfield Switch Problems
The following Sega games employ unique playfield "Stand Up" targets:
- Goldeneye
- Twister
- Space Jam
- Star Wars Trilogy
- The Lost World Jurassic Park
- Starship Troopers
- Viper Night Drivin'
- Lost in Space
- Godzilla
- Harley-Davidson
They are self-contained modular targets that are quite easy to remove or replace. The target "faces" may be purchased separately and may be interchanged easily. The unit has a self-contained diode, like all switches that are sensed via a switch matrix. It also contains a small micro-switch, that the "tail" of the target face actuates. The "Achilles Heel" of this target system is the IDC connector. As with all IDC connectors, the wires can pull out fairly easily.
- Sega Modular Targets (from Starship Troopers
An example target. The target "faces" are interchangeable. 
"Exploded" target parts. The gray switch part must be oriented correctly. Note the integrated diode just under the micro-switch, center/bottom. 
The Achilles Heel of a Sega target...the IDC connector. 
The first step to disassemble a target. Slide the rear face of the target assembly up. 
Testing a closed target switch, step 1. In diode test, with the switch closed, your meter should read 0 or null. 
Testing a closed target switch, step 2. In diode test, with the switch closed, your meter should read .5 to .7, the nominal voltage drop across a diode.
4.7.2 Opto Switch Problems
A little background regarding how White Star games handle opto switch pairs is necessary. With White Star games, opto switch pair closures are analyzed by the CPU in the same manner as leaf switch pairs or normally open (NO) microswitches. In other words, when a leaf or NO microswitch closes, the end result is identified by the CPU as a valid switch closure.
Again, to briefly summarize the operation of White Star opto boards, if an object is blocking the light beam between the transmitter opto LED and the receiver opto LED, the CPU detects this as a switch closure. When an object is not present to break the light beam, the CPU detects this as an open switch. The components used on the opto receiver board are designed to do as such.
The transmitter side is simply an ultra-red LED with a current limiting resistor. The receiver opto is an identical ultra-red LED. As the receiver LED, when light of the appropriate wavelength (from the transmitter) shines on the LED, a small amount of voltage is "excited" in the LED. By using discrete components on the receiver side, that small voltage is detected and the appropriate signal is sent to the CPU via the switch matrix return (row). By employing such a design, failure on the receiver opto side is more common.
- Sega/Whitestar Transmitter, Receiver, and Opto 'Long Hop' Board Pair, as found on Starship Troopers. Note that these ultra-red LEDs aren't red until power is applied.
The opto transmitter side. 
The opto receiver side, with accompanying electronics. The red colored LED is a diagnostic aid to indicate a detected switch closure. 
An opto pair. The pair must be in perfect alignment or the opto switch will operate unreliably.
This particular system is contrary to how Bally / Williams WPC CPUs handle opto pairs. Equally, WPC games employ infrared (IR) opto switch pairs. If interested in learning the theory of operations for the White Star opto trough upkicker boards, please consult the manual. Sega / Stern have included some excellent, detailed, technical documentation within their manuals. Stern Service Bulletin #67 includes detailed theory of operation of these opto switches too.
4.7.2.1 Two Balls Served, Continuous Balls Served to the Shooter Lane, or the Trough VUK Fires Repeatedly
Common problems with some White Star games are:
- Two balls are served to the shooter lane.
- Balls are continuously served to the shooter lane.
- The trough VUK repeatedly fires, when there are no balls above the VUK trough plunger.
Depending on the exact circumstances, and the era of the White Star game, one or two of these symptoms can occur. The crux of the problem is either one or both of the two trough LED opto transmitters or receivers is failing. Rarely do the components on the trough opto boards other than the red LEDs actually fail though. And in most cases, it is not the LED itself, although, there are some instances when the problem is a failing LED. It is noteworthy that the issue is more common to the opto receiver side more so than the opto transmitter side.
If the any of the previously mentioned symptoms are evident, the best approach is to first put the game into "Clear Ball Trough" mode via the Portal buttons on the coin door. Consult the manual documentation for details how to enter this test. Once all of the balls are removed from the trough, no balls should display on the DMD display. If either of the two images shown to the left are displayed on the DMD, and the ball trough no longer has any balls present, there is a problem with either the transmitting or receiving opto boards.<br=clear all>
The first thing is to observe the two red opto LEDs on the transmitting board. This board is located on the backside of the ball trough. If the transmitting LEDs are lit, there probably is not a problem with them. However, this is not always necessarily the case. Secondly, inspect the opto LEDs on the receiving board. To do this, the game will have to be turned off, and the receiving opto board removed via the three screws which attach it to the trough. Look for hairline cracks around the .100" angled header pin solder joints. Likewise, inspect the solder joints around the opto LEDs. If cracks are evident in any of these locations, remove, and apply fresh solder to these connections. Reinstall the receiver board, and observe the results. Conversely, if hairline cracks are not found, or if the same symptoms are still evident after reflowing solder joints, replacement of the LED optos is suggested.
White Star games initially used MT5000UR ultra-bright red LEDs, while later games used TLRH180P ultra-bright red LEDs for both the transmitter and receiver boards. Both styles of LEDs have become expensive and fairly difficult to source. Great Plains Electronics offers the MV8114 as viable replacement for either original, factory LED. The only caveat is that both the transmitter and receiver opto LEDs must be replaced in pairs to ensure proper function.
When replacing the opto LEDs, make certain the base of the LED is placed squarely on the PCB. An LED which is poorly installed may result in sporadic switch closures.
Please note that a "Lock Ball Assembly" was employed in the trough design on early White Star games. The lock ball assembly is a unit, which was carried over from later Data East and early Sega games. It consists of a coil mounted horizontally above the left side of the trough VUK. This assembly was later removed presumably either due to cost factors, or so this coil assignment could be used as a playfield coil feature elsewhere instead.
If a lock ball assembly is used in the game, and trough opto failure has occured, the symptom will more than likely be that the trough VUK will fire repeatedly without a ball present above the VUK plunger.
4.7.2.2 Phantom Opto Switch Closures
Similar to the discussion above, "Two Balls Served, Continuous Balls Served to the Shooter Lane, or the Trough VUK Fires Repeatedly", other opto pairs in the game may fail over time and become unreliable. Usually this manifests as phantom switch closures. Games like Starship Troopers that use an opto pair for both the left and right orbit shots my score the orbit shot randomly or even continuously. If the "long hop" opto assembly is removed, you may find that the opto pair registers correctly if the optos are aimed with great accuracy at one another. However, the slightest misalignment (like flexing the PCB) will cause the opto pair to register a "hit".
The correction for this is again to replace the original MT5000UR or TLRH180P ultra-bright red LEDs, with MV8114 LEDs from Great Plains Electronics.
4.8 Display problems
4.9 Sound problems
Basic operation (simplified) of the White Star CPU/Sound board audio part: The main CPU (U200) makes sound calls to the sound CPU (U6) which instructs the BSMT to play a certain sound. The BSMT fetches the required data (sound sample) from the ROM memory (U17-U21-U36-U37) and feeds the 16-bits wide parallel data to a conversion circuit which makes it serial data (shift register, U23-U24). The serial data is fed into a DAC (U26, Digital to Analogue Converter) that outputs to a pre-amplifier (U30, OPAMP). The output from the pre-amplifier is fed into the TDA2030A amplifiers at U101/U102 and sometimes U100 (some boards have 3 amplifiers, one for each speaker) and from there the audio signal goes to the speakers.
The sound section is quite reliable, the failure occuring most is a broken amplifier (TDA2030A).
Sound missing from one of the speakers: Most likely a broken amplifier (TDA2030A)
No sound at all: Check the voltages on the board. On the DC input connector CN2 there should be approx. +12V DC between pin 2 (GND) and pin 6 (+12V) and -12V between pin 2 (GND) and pin 3 (-12V), these voltages come from the Power Supply Board. On the board itself are two voltage regulators to convert the +12V and -12V to +5V and -5V for the pre-amplifiers, check these voltages by measuring between the ground (GND, test point) and U30 pin 8 for +5V, U30 pin 4 for -5V.
Other causes of no sound at all are the U7 game ROM being corrupted or improperly seated. You can re-seat this ROM and it often solves the issue. If any of the voice ROMs (U17, U21, U36, U37) are corrupted or improperly seated, the sound will still work but will be corrupted or have intermittent issues such as scratchy sounds or improper sounds at specific times.
Finally, if you have no sound at all, you might also want to check that you have the correct sound board. Some operators may have swapped the 520-5300 with a 520-5136 board for the older series whitestar games. The 5300 board will work in all whitestar systems. The 5136 will work but will present no sound at all in all games newer than lord of the rings (2003).
Samples playing randomly This happens on CPU boards that have the BSMT2000 emulation chip rather than the original (which Stern could not source cheaply enough at that time). You need to update the emulation using the method in Stern service bulletin 157: http://www.sternpinball.com/ROM_bootFLASH.html
Loud hum/burnt speakers/12V DC coming out of the speaker connector If you have a machine with all speakers dead, check for voltage on speaker wires. If the -12V wire from the driver board to the CPU board is disconnected, it can cause 12V DC to be sent down the speaker line, causing a loud hum and fairly quickly destroying any speakers connected!
4.9.1 Adding a Second Backbox Speaker to some Sega Games
A chap named Martin Riley submitted a nice article to the PinballNews explaining how to add a second backbox speaker to games like StarShip Troopers.
From the article...
"Mid-life Sega games from Twister through to and including Viper Night Drivin' only had the left hand backbox speaker plus the cabinet speaker and only two of the 3 audio amps are populated on the CPU board.
Late Sega games from Lost in Space onwards have two backbox speakers but they are effectively mono as they are both connected to the left channel audio amp on the CPU board (the right channel amp being unpopulated)."
The complete article can be found at http://www.pinballnews.com/learn/speaker/index.html
The article lists all components required to add the 3rd speaker channel. Some (maybe all) two channel boards are not stuffed with C122, which is not listed in article parts list. You'll need one more 0.1µF axial ceramic capacitor for C122.
Adding a 3rd speaker to StarShip Troopers improved the sound quite a bit. The sound is richer and cleaner. The emphasis on some sounds is more pronounced and easier to hear. Mounting the additional speaker to the "blank plate" required drilling the rivets that attach the speaker grill, and replacing them with low profile head screws. This is only necessary for Sega "Showcase" backbox games. For games like Independence Day, mounting the additional speaker should be trivial.
4.10 Flipper problems
4.11 Pop bumper problems
5 Game Specific Problems and Fixes
Lord Of The Rings
If your Balrog stops registering hits, a little checking will sort it out. The mini microswitch with a roller arm used to register hits may need adjusting. Known past problems are a flaky or bad switch, and/or wiring. The Balrog moves in such a way that wires can break inside where you can't readily see them. It's easy to check the switch and wires with a meter. The wires push into an IDC connector nearby; be sure they are pushed in tight.
There isn't any adjustment for the micro switch, except for bending the blade with the mini-roller; try bending the blade outwards slightly. According to the manual, sw #28 stays normally closed and then a Balrog hit opens the switch. This is not the normal target arrangement. So using the Balrog test mode in diagnostics, the switch should stay solidly closed, and then only open when Balrog is tilted forward.
The Shire and Gimli VUK switches.
These get hammered on LOTR and will eventually need replacing, There isn't any easy solution other than replacing the flaky switch. The tiny black screws on the Stern switches are 3/16". You will need a nut driver that size if you want to attempt replacement of the switches.
The Shire (and Gimli) VUK switch, are fork blade microswitches. Stern part number 180-5116-01.
Spec on side of switch says Cherry .1A 125v E63. Try parts4pinballs.com or your favorite Stern parts supplier.
The Shire VUK.
It's easiest to remove the entire Bottom Left VUK coil and bracket from under the PF (playfield) to change the fork switch.
Take out the two largest bolts first, using a cross-head (phillips) screwdriver on the top and 11/32" nut runner (or socket) on the bottom.
Remove the metal VUK arch from the top of the playfield.
Remove the two lower wood screws (1/4" drive) leaving the one on the corner near the T-nut.
Supporting the Coil Bracket, remove the last 1/4" screw.
Unclip the connector from the coil and VUK. Remove coil and bracket assembly.
Microswitch small screws are 3/16". As stated before, to remove the switch correctly you need a nut driver (or socket) that size.
You should be able to slide the heatshrink tubing all the way up the wires, solder on the new switch and then slide them back down in place. If not, use new heatshrink tubing. Assembly is above steps in reverse. Test in switch tests before replacing assembly and then by throwing a ball in the Shire in attract mode one the assembly has been correctly replaced.
6 Repair Logs
Did you do a repair? Log it here as a possible solution for others.
Striker Xtreme: Problem: Display is blacked out or only coming on for a few seconds before blanking out.
Cause: Resistors R6 and/or R7 on the display power supply board have gone bad (open or increased in value).
Solution: Replace resistors R6 AND R7 on the display power supply board. Both are 330k @ 1/2 watt