Bally Home Models

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1 Introduction

Series 1 machines are designed around the Mostek 3850 CPU chip. The power supply for Series 1 was very poorly and cheaply designed. It had virtually no fuses and frequently went over-voltage and destroyed the CPU chip on the game board. Connectors frequently burned up.

Series 2 machines are designed around the Mostek 3870 CPU chip. The power supply for Series 2 machines was vastly improved in that it had circuit breakers for some voltages and the circuitry was simplified. However, it still was not a very good power supply. The AC power input connector on the power supply board would burn up.

2 Games

2.1 Series 1

• 606-1000 Fireball
• 614-1000 Evel Knievel
• 614-3000 Fireball

2.2 Series 2

• 614-2000 Captain Fantastic
• 614-4000 Galaxy Ranger
• 614-5000 Fireball

3 Technical Info

Coil cross reference:

Midway # A614-00014 (red wrapper) 4.3 ohms resistance is the same as Bally # AP-24-725. These are typically used as thumper bumper coils.

Midway # A614-00016 (blue wrapper) 1.4 ohms resistance of the main winding, 16.5 ohms resistance of the hold winding is the same as Bally # AF-23-300/28-1000. These are typically used as flipper coils.

Midway # A614-00017 (white wrapper) 3.8 ohms resistance is the same as Bally # AP-23-750. These are typically used as slingshot kicker coils.

Midway # A614-00047 (yellow wrapper) is the same as Bally # AP-23-575. These are typically used as the outhole (ball return) kicker coil.

Schematics are posted at this website:

http://www.tinlin.net/jim/pinball/schematics.html

Self test switch location on board

The self test switch is located on the game board right next to the 50k/100k replay score selection switch. Both are slide switches and can be easily accessed while the board is mounted in the backbox.

The C connector on the game board

The C connector goes to and from the cabinet and is 23 pins. DC power to operate the board logic, switched illumination, and solenoids go through this connector. The Tilt Switch, Start Switch, Speaker, Playfield Solenoids, and Backbox general illumination are also routed through this connector. The pinout of this connector is as follows:

1: +18VDC 2: 18 volt return 3: VLED display return and common ground 4: Speaker + 5: Common ground (Blue-Red) 6: +V for LED display 7: 6 VAC for GI lamps on playfield 8: 6 VAC for GI lamps in backbox 9: 6 VAC for GI lamps in backbox 10: 6 VAC for GI lamps on playfield 11: Key 12: +5 VDC (Brown-White) 13: SW1 strobe common to tilt switch and start switch 14: Tilt Switch 15: Start Switch 16: Solenoid 5 (Left Thumper Bumper) 17: Solenoid 4 (Right Slingshot) 18: Solenoid 7 (not used) 19: +22 VDC (approximate) to flipper coils 20: Solenoid 6 (Right Thumper Bumper) 21: Solenoid 2 (Outhole Kicker) 22: Solenoid 1 (not used) 23: Solenoid 3 (Left Slingshot)

The D connector on the game board.

The D connector goes to the playfield and is 24 pins. This is for the lamp matrix and switch matrix.

Identifying markings of a Series 2 game board.

A Series 2 game board has these numbers silkscreened on it.

4 Problems and Solutions

4.1 Power Problems

Series 2 power transformer box assembly uses Littlefuse twist tab mount circuit breakers instead of fuses. The red shaft of the circuit breakers stick out the rear of the cabinet in a slot. There are three 2.5 amp hold, 4.0 amp trip breakers and two 3.9 amp hold, 6.0 amp trip breakers mounted to this transformer box.

The gray wire from a 2.5 amp breaker feeds the controlled (switched) illumination circuit. The black wire from a 2.5 amp breaker feeds the left thumper bumper and left slingshot coils. The yellow wire from a 2.5 amp breaker feeds the right thumper bumper, right slingshot, and outhole (ball return) coils. The brown wire from a 3.9 amp breaker feeds the 6 volt playfield general illumination circuit. The blue wire from a 3.9 amp breaker feeds backbox general illumination and gameboard logic supply. There are two windings of the power transformer that are NOT fused: the 120 volt primary and the 18 volt (red wires) secondary. The power transformer used in the Series 2 power box is Midway # MT-60A.

Power transformer and circuit breakers are inside the black metal box.

Notice the primary of the transformer is NOT fused! It would be a good idea to install a fuse.

Series 2 Power Supply board. The AC power from the transformer goes to the connector on the left side of the board. The DC output to the gameboard and playfield coils is through the right side connector.

Closeup view of the AC input connector which usually burns up showing wire colors and sequence.

AC input connector A pin numbers.

DC output connector B pin numbers. Pins 6 and 7 feed 5.5 volts AC to the playfield general illumination.

4.2 MPU boot issues

4.2.1 Relocating the battery from the MPU board

The Bally home model pinball machines did not utilize any on-board batteries for data storage, and thus there is no need for any battery relocation methods or repair of damage due to battery leakage.

4.3 Game resets

On the series 2 gameboards, the cpu chip (Mostek 3870) is installed in those troublesome orange colored sockets. Replace the socket with a good quality 40 pin IC socket. The clock crystal next to it is a 3.579 mHz television color burst crystal.

Mostek 3870 technical information links:

http://www.cpu-museum.com/Bilder/Mostek_3870_BD_1.jpg

http://www.cpu-museum.com/Bilder/Mostek_3870_PL_1.jpg

4.4 Solenoid problems

All solenoids are "pre-driven" by integrated circuit Q203 (DM7445). Solenoid driver transistors are type SE9400 which cross reference to NTE 264.

Transistor S4 controls the right slingshot and is driven from IC Q203 pin 5.

Transistor S5 controls the left thumper bumper and is driven from IC Q203 pin 6.

Transistor S7 is not used on this machine and it as well as two resistors next to it are not installed. This solenoid would be driven by IC Q203 pin 9.

Transistor S6 controls the right thumper bumper and is driven by IC Q203 pin 7.

Transistor S1 is not used on this machine and it as well as two resistors next to it are not installed. This solenoid would be driven by IC Q203 pin 2.

Transistor S2 controls the outhole (ball return) kicker and is driven from IC Q203 pin 3.

Transistor S3 controls the left slingshot and is driven from IC Q203 pin 4.

Above pertains to Captain Fantastic.

4.5 Lamp problems

The home model pinball machines use wedge base lamps (except for the pop bumper lamps) throughout the machine. Originally equipped with number 147 miniature lamps, you can substitute the more common number 555 pinball lamps or even number 159 or 259 lamps. Bally installed number 455 bayonet based blinker bulbs in the pop bumpers. The power supply provides 5.5 volts Dc to the switched illumination circuit and 5.5 volts AC to the general illumination circuits.

4.6 Switch problems

The playfield switches are all microswitches attached to two large printed circuit boards screwed to the bottom of the playfield. They are kind of oddball microswitches, but it should not be too hard to fabricate replacement switches if you had to.

4.7 Display problems

Score display assembly on a Series 2 game board.

4.8 Sound problems

Volume control is on board.

Volume control as shown from solder side of Series 2 game board. This is what you see when you take off the back panel of the machine.

Volume Control pot.

Volume control (25 k pot) as shown from parts side of Series 2 game board.

Sound circuitry consists of preamplifier IC Q202 which is a type LM3900 (crosses to an NTE992) and output IC Q201 which is a type ULN2074B. The output to the speaker comes from IC Q201 pin 10.

4.9 Flipper problems

Bally home model part number conversions to the more common Bally commercial part numbers.

0606-00030-0000 Coil Stop Bracket use # A-613-67

0017-00009-0343 Front Coil Bracket use # P-108-53

0010-00246-0000 Return Spring use # SP-200-185

0606-00029-0000 Plunger & Link Assembly use # A-3714-1

0017-00104-0073 Spring (Wave) Washer use # P-1158-6

0017-00009-0330 White Nylon Bushing use # C-649-53

0017-00009-0360 Mounting Bracket Assembly use # P-6264-134

0606-00017-0000 End Of Stroke Switch Assembly use # ASW-A20-23

0606-00038-0000 Left Lever Arm Assembly use # A-3711-2

0606-00037-0000 Right Lever Arm Assembly use # A-3711-3

0017-00101-0338 Set Screw use # M-1369

0017-00009-0342 Flipper Stop Bracket use # P-6665-444

0017-00104-0074 Nylon Washer use # P-801-590

Complete flipper unit assembly.

This is a picture of a complete flipper unit on a Captain Fantastic home model pinball machine.

Flipper coil diode.

Diode on flipper coil.

Flipper Bat Assembly parts:

0017-00042-0142 White Flipper Bat Housing use # C-611-5 White

0017-00009-0357 Flipper Rubber, Red, 1-1/2" diameter by 1/2" tall

0606-00039-0000 Shoe & Shaft Assembly use # A-2747-11

Flipper Button Assembly parts:

0017-00042-0144 Flipper Button use # C-905

0017-00042-0143 Flipper Button Housing use # C-904

0017-00009-0366 Flipper Button Mounting Plate use # P-1566

0606-00016-0000 Flipper Button Cabinet Switch Assembly use # ASW-A10-41

4.10 Pop bumper problems

Pop Bumper part number conversions. Original Bally home model part numbers to the more common commercial Bally part numbers.

0017-00042-0122 Pop Bumper Body use # C-114-3

0017-00042-0121 White Pop Bumper Skirt use # C-790-1

0017-00042-0123 Base use # C-115-1

0010-00236-0000 Base Spring use # SP-200-177

0606-00040-0000 Rod & Ring Assembly use # A-1873

0017-00009-0339 Fibre Yoke use # P-3656

0017-00009-0338 Steel Yoke use # P-3656-5

0606-00728-0000 Plunger use # S-496-118

0606-00033-0000 Mounting Bracket Assembly use # A-613-1

Pop bumper assembly.

Pop bumper assembly under the playfield of a home model Captain Fantastic.

4.11 Slingshot Kicker Problems

Slingshot kicker assembly below the playfield on a Captain Fantastic.

Close up view of the diode on the slingshot kicker coil.

Bally home model part number cross reference to Bally commercial pinball part numbers.

0606-00033-0000 Slingshot/Pop Bumper bracket use # A-613-1 or B-7417

A614-00017-0000 Coil use # AP-23-750

A614-00005-0000 Kicker Arm Assembly use # A-3459-1 (plastic top sleeve is # C-1062)

0606-00043-0000 Plunger and Link Assembly use # AS-2586

0017-00007-0073 Roll Pin, 1/8 x 7/16, use # P-1637-58

0017-00100-0021 Retaining E Ring use # P-6316-5

0010-00239-0000 Compression Spring use # SP-200-180

5 Repair Logs

Captain Fantastic:

Symptom: All coils energized and stay energized when you turn on the power to the machine.

Cause: CPU chip is corrupted. Generally caused by the power supply +5 volts going overvoltage

Solution: Check and repair the power supply board first. If game still does not boot you need a new CPU chip (very hard to find today).