Mattel

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1 Introduction

Mattel Electronics manufactured one model of electronic home model pinball machine. Mattel no longer has any manuals, information, or parts for this machine.

2 Games

• Las Vegas, 1977, 4 players

Playfield of Las Vegas

closer look at playfield

Las Vegas backglass

3 Technical Info

Mattel issued two manuals for "Las Vegas" pinball, an owner's manual and a service/parts manual. The Owner's Manual is part number 2442-0920. The Service Manual is part number 0007-2880.

Service and Owner's manuals

Owner's Manual is available to download here: http://mattelhomepin.blogspot.com/p/users-manual.html

A better copy in pdf form is here: Mattel Las Vegas Owner's Manual

The Service Manual is here: Mattel Las Vegas Service/Parts Manual

Complete schematic on 11 x 17 page

Las Vegas pinball machine is covered by the now expired patents number 4162793 (game computer board) and 4203602 (metal ball used as a switch between two "hot" contacts).

IC1 is a Rockwell PPS-4/1(MM77) microcomputer, 4 bit, 1344x8 MROM, 96x4 RAM, 31 I-O/2 interrupt lines.

Transistor type 224N1 is in reality a 2N3904 (or NTE123AP).

Transistor type 223P1 is in reality a 2N3906 (or NTE159).

4 Problems and Solutions

4.1 Power Problems

The two conductor power cord goes to an on-off switch on the primary side of the power transformer. Please note the schematic shows there is no fuse on the primary side. There are two secondary windings on this transformer. One secondary provides 26 volts AC to bridge rectifier BR2 to get the 30 volts DC for the coils. This connects to points W4 and W6 on the game board and is protected by circuit breaker CB2 (2.0 amps). The other secondary provides 16.5 volts AC to bridge rectifier BR1 to get -16 volts and other regulated lower volts to the game logic, sound, and switched & general illumination. This connects to points W2 and W3 on the game board and is protected by circuit breaker CB1 (3.0 amps).

Voltage Regulator IC9 (type 7915) creates the -15 volt source.

Bridge rectifiers BR1 and BR2 are both type RC204-1 which are rated 2 amps @ 400 volts. It is strongly suggested to upgrade these to 8 amps @ 400 volts such as Radio Shack # 276-1181.

4.2 Solenoid Problems

All solenoid driver transistors are "pre-driven" by integrated circuit IC8 (type LM3900).

Transistor Q6 (type SE9400) drives pop bumper #1 coil. It is pre-driven by IC 8 pin 5.

Transistor Q7 (type SE9400) drives pop bumper #2 coil. It is pre-driven by IC8 pin 4.

Transistor Q8 (type SE9400) drives the slingshot coil. It is pre-driven by IC8 pin 10.

Suitable replacement transistors for the SE9400 are: TIP145, TIP107, 2N6040, 2N6042, NTE264.

Sentinel/Wonder Wizard coil number 361669001 (a.k.a. # 1669-1) is used for the pop bumpers and slingshot coil. If your machine came with standard coils for the flippers and not the alternate (laminated) unit, you can also use 361669001 coil. If the 361669001 coil cannot be located, you can substitute a Williams AE-23-800-01 coil instead and be sure to observe diode polarity.

4.3 Lamp Problems

General Illumination circuit for the backbox are through connector C9 on the black and yellow wires. General Illumination for the playfield circuit is through connector C9 on the red and brown wires.

The playfield switched illumination is through connectors J3 and J5. Lamps associated with connector J3 go through resistor pack RP1 and integrated circuit IC4 (type ULN2002), then fed into custom CPU chip IC1. Lamps associated with connector J5 go through resistor pack RP2 and integrated circuit IC7 (type ULN2002), then fed into custom CPU chip IC1.

All lamps are # 1892 or # 1813 which are 12 volts.

4.4 Switch Problems

Original ball and chain tilt assembly

Williams A-15361 Tilt Assembly

The original "ball and chain" tilt assembly is very flimsy and not very good. It is suggested to replace it with a Williams # A-15361 Tilt Assembly for much better operation since it uses standardized parts.

You can also use these Marco Specialties parts along with two 6-32 wing nuts to make a complete tilt assembly:

(1) # 04-10346 and (1) # 20-6502-A

Playfield standup switch on Las Vegas

The standup switches look like bent up paper clips just like the switches on Sentinel/Wonder Wizard home pinball machines. These switches must be kept clean and shiny to work properly. The circled area is the switch. The playfield switch circuits go through connectors C1 and C4.

Playfield switches go through connectors J4 and J1. Integrated circuit IC6 (type CD4069B) and resistor pack RP3 handle the switches going through connector J4. Integrated circuit IC3 (type CD4584B) and resistor pack RP4 handle most switches going through connector J1. Switches BS1 (ball in play), BS2 (ball out a.k.a. outhole), SW3 (handicap), and SW4 (game select) go through resistor pack RP5 then to the custom CPU integrated circuit IC1. If a playfield switch is stuck closed, machine will not boot up. Unplug connectors J1 and J4 (which go to the playfield switches) then try powering on the machine. If a playfield switch was stuck and the switches are unplugged from the board, it should now boot up.

4.5 Display Problems

The vacuum fluorescent score display is mounted on it's own board in the backbox and connected to the gameboard with a cable to connectors J10 and J11 on the game board. Integrated circuit IC 2 (Rockwell # 10934 spider chip) is the display controller and feeds the display information out to connectors J10 and J11 through resistor packs RP6 and RP7.

4.6 Sound Problems

Sound comes out of custom integrated circuit IC1 pin 42. Resistors R9, R10, and R11 connect to the 3 position volume slide switch to provide three levels of volume. Transistors Q4 and Q5 are the amplifiers which feed the 4 inch speaker (45 ohms @ 1 watt).

4.7 Flipper Problems

Standard flipper unit for Las Vegas

Datasheet for Dormeyer 1504-M-1 laminated solenoid

Some Las Vegas pinball machines came with an alternate flipper coil assembly which consisted of a Dormeyer 1/2" stack laminated 24 volt AC solenoid. Dormeyer part number 1504-M-1. It has a coil resistance of 2.3 ohms and can draw up to 9 amps current. Even though this solenoid is designed for 24 volts AC operation, this machine operates it on 24 to 30 volts (approximate) DC.

Regardless of which flipper unit assembly was installed in your machine, one solenoid operates two flippers via a connecting rod/linkage. Both the standard flipper unit and the alternate (Dormeyer) flipper unit have high wattage resistors connected to the coils through the end-of-stroke (E.O.S. ) switches. When the EOS switch is closed, full power is applied to the coil. The coil moves the linkage to open the EOS switch which cuts in the resistors to limit the current to the coil to prevent the coil from burning up. The coil is rated for intermittent duty only.

4.8 Pop Bumper Problems

Each of the above the playfield pop bumper parts are the same as the Sentinel/Wonder Wizard home pinball machines. There is a metal ring glued to the playfield that is one contact of the pop bumper switch circuit. The metal rod & ring of the pop bumper is the other contact of the pop bumper switch circuit. The metal pinball touches the playfield metal ring and then makes contact with the metal rod & ring assembly which completes the circuit to both activate the coil and to score points. This design relies on the contact surfaces to be clean and shiny to make proper contact to trigger the pop bumper.

Transistor Q6 (type SE9400) on the gameboard drives pop bumper #1 and Q7 drives pop bumper #2.

4.9 Slingshot Problems

One coil drives both slingshot kickers through the use of a metal wireform linkage. Transistor Q8 (type SE9400) on the game board drives the slingshot coil.