arcade game animation The Todd MacCulloch Restorations
Brought to you by: www.GameRoomRepair.com    

This is an article that I wrote for Gameroom Magazine. It was published in the February and March 2007 issues. Please visit my website at http://www.GameRoomRepair.com for more information on my restoration services and for pictures of the games in my personal collection. I can provide a quote for anything from minor repairs to complete "Grade-1" restorations. My abilities include Solid State and Electro-mechanical repairs. I also work on Solid State and Vacuum Tube amplifiers for jukeboxes and radios. I can also repair other items like antique clocks, phonographs, music boxes and Lionel trains. I hold a degree in Electronics and teach the same at my local community college. I troubleshoot down to the component level using the oscilloscope and other test equipment in my repair shop. In addition, I was a "tool and die" machinist at my first job in the 1980’s. I have a metal lathe, milling machine, gas and arc welders and a full array of wood working tools in my shop. I can manufacture many metal, wood and plastic parts that are no longer available for your machine. My labor rate is $60 per hour for all services.


The Article: Part 1

Todd MacCulloch When a former NBA star (now a sports announcer) contacted me to repair two of his arcade games, I was honored. When I learned how rare these games are, I decided to share this experience with Gameroom Magazine. Todd MacCulloch played for the Philadelphia 76ers from 2000 until 2003. He is now a Radio Color Analyst for the 76ers. He contacted me after seeing pictures of my Kasco Untouchable on my website. He asked if I could repair his Untouchable. This would require the game to be shipped from his home in Washington State, to my workshop in Santa Maria, California. We talked on the phone and worked out the details for shipment. During the conversation, Todd asked me if I might be able to repair another machine in his collection called the Quarter Horse Derby which was made in the 70s by a company called Games Of Nevada. I was not familiar with this game but told him that I would be happy to inspect it and provide an estimate to repair. So a few weeks later, North American Van Lines pulled up to my door and dropped off these two games. I looked them over, sent Todd an estimate and he authorized the repairs.

Kevin and the Quarter Horse Derby I decided to tackle the Quarter Horse Derby first. This machine is a cross between an arcade game and a Las Vegas style payout gambling device. For the drop of a nickel, nine mechanical horses line up at the starting gate then patiently wait for the player to wager his bet on the nag of choice. Multiple coins can be inserted and bet on multiple horses if desired. When all the bets are in and the Start Race button is pressed, the player is treated to a fully animated horse race which consists of nine phillies that gallop around an oval track, jockey for position, each pulling ahead of the other then falling behind again, seemingly at random, until the home stretch where one of the horses pulls ahead of the others to become the clear victor in The Run for the Roses. When the winning horse hits the finish line, the other horses stop moving until the next game is started.

Quarter Horse Derby race track In this picture, a race had just concluded and you can clearly see who won the race. If the player was lucky enough to bet his coin(s) on the winning nag, he is promptly rewarded with the sound of nickels plunking into the payout tray below. The payout for each coin played ranges from three to one hundred nickels. The amount of this payout (called the “Odds”) is randomly chosen when the player inserts the first coin and is displayed on a rotating Odds Drum in the headboard of the machine. The machine allows the player to wager up to nine coins on any horse. If nine nickels are bet on a horse that is displaying 100:1 odds and that nag comes in first, the lucky player wins 900 coins or a cool $45.00.

Quarter Horse Derby back glass This is the cabinet backglass. The small squares are clear windows, through which the paypout odds can be read.

Quarter Horse Derby starting gate To start the repair process, I carefully compared the game’s schematic to the components and wiring inside the machine. I found that this game had a few modifications performed to it. The most significant change was made in the Starting Gate circuitry which is shown here.

Quarter Horse Derby starting gate When the first coin is inserted at the start of a new game, all horses advance to the Starting Gate and are stopped by the leading vertical edge of this gate. This picture shows the Starting Gate in the closed position with one of the horses fully advanced and waiting at the starting line. The condition shown here, is the machine at rest just after the last race has ended. I'm pointing to the white peg of the winning horse, that contacted the bar and microswitch to end the race.


Quarter Horse Derby computer Quarter Horse Derby wipers

When all the bets are in and the race is started, a powerful solenoid (seen several pictures above) energizes and swings the gate open so that all horses can begin to move around the track. This solenoid is required to hold the gate open long enough for all horses to complete the first quarter mile, which is around the first curve in the oval track, so that they clear the starting gate. By studying the schematic, I realized that this large solenoid was not original. In fact, the original circuitry consisted of three separate solenoids which were a Gate Kicker Solenoid (to start the gate swinging open), a Rotary Solenoid (completes the gate swing to fully open and latches it in place), and finally a Gate Release Solenoid closes the gate after the horses have passed it). Apparently, some of this original circuitry had failed in the past and rather than using the correct parts to fix the machine, the repair person chose to replace everything with one giant brute strength solenoid. This change in solenoid circuitry also required changes in the electrical box that controls the entire game, none of which were noted on the schematic. One of these changes was the addition of an extra wiper blade to the Sequencer Disk, which is the main timer that controls the sequence of operations for the entire game. (I'm pointing to the wipers in the picture above) Needless to say, this made the repair a bit more challenging due to the fact that I had to trace many wires and document the differences between the game wiring and the schematic.

For anyone who does electro-mechanical game repair, you will understand that the majority of work needed on this game was the typical cleaning and adjusting of all electrical contacts, then lubricate and adjust all mechanical assemblies. However, there were a few additional repairs that required the use of my lathe and milling machine in my shop. Before I describe these repairs, a brief description is needed of how the game is supposed to operate. When the horses race around the track, they actually have a gallop to their movement and they jockey for position. Each horse at random will pull ahead of the others for a short distance, but then slow down and become overtaken by another horse. All horses stay within one half length of each other, so the race seems very close and the winner is hard to predict until the end of the race. Only during the home stretch does the winning thoroughbred pull away from the rest of the pack and hit the finish line first, several lengths ahead of the others. The electro-mechanics that cause this are quite ingenious. Each of the nine horses is connected to a chain under the race track.


Quarter Horse race track These chains are connected to a stack of clear plastic Drive Wheels which are all driven together by a two speed double stack motor. One speed on this motor is faster than the other and is used to quickly move the horses to the starting gate when the first coin is played. During the race, the motor toggles back and forth between fast and slow speeds depending on whether the horses are in the straight sections of the race track, or the oval sections of the race track. This speed change during the oval sections of track is necessary to give the horses the appearance of consistent speed at all times. However, this changing motor speed during the race does not cause the horse’s galloping or jockeying rhythm. That motion is caused by Horse Blocking Relay armatures. These arms drop into notches that are cut into the outer circumference of each clear plastic Drive Wheel. I am pointing to one of these Horse Blocking Relay arms in the picture above, and I am pointing to the Drive Wheel notches in the following picture.

Quarter Horse Derby drive wheels There is one blocking arm for each horse’s Drive Wheel. During the race, the double stack motor attempts to turn all nine Drive Wheels in unison which would normally advance all nine horses around the track in a smooth consistent motion. However, the Sequencer Disk controls a circuit that allows the blocking arms to engage the notches and grab onto each Drive Wheel. This grabbing of each Drive Wheel happens in an intermittent and repeating fashion. The double stack motor continues to turn, but as each Drive Wheel is grabbed, the associated horse stops dead in his tracks. When this occurs, the Drive Wheels are allowed to slip on the motor’s drive shaft due to leather friction disks that connect each wheel to the drive shaft. The duration of blocking arm engagement is very brief, only about one half second. When the blocking arm retracts and clears the Drive Wheel, the wheel starts to turn again and the horse continues down the track. The frequency at which these Horse Blocking Relays grab and release each Drive Wheel causes the visual effect of the horses galloping as they advance around the track. The jockeying of horse’s position (relative to each other) is controlled by a separate disk and wiper assembly inside the electronics box. Only during the last quarter mile of the race (the last straight away before the finish line) does the winning nag immerge from the pack and hit the finish line several lengths ahead of the others. This final sprint to victory occurs when the Horse Blocking Relay of the winning nag is retracted permanently which allows that horse’s Drive Wheel to rotate continuously. The other phillies are still being intermittently blocked but the winner takes off at breakneck speed to claim the Triple Crown. As the winning horse hits the finish line, the race is ended by a white plastic knob that is mounted on the horse’s drive chain.

Quarter Horse Derby starting gate This knob presses against a vertical bar which is mounted on the leading edge of the Starting Gate. When this vertical bar gets moved by a white plastic knob coming into contact with it, a micro switch is closed and the electronics box stops the race. I am pointing to one of the knobs in figure eight. Now that we have an understanding of how the game operates, I can describe the first major problem that required my attention. Every time this game was played, the horses numbered two and nine would always finish ahead of the others and they would tie for first place. The electronics box was actually picking a random winner each game, but no matter whom the real winner was, horses two and nine always finished first. This problem turned out to be worn notches on the number two and nine Drive Wheels. The notches, which are normally square, were rounded off to the point that the armature of the Horse Blocking Relay did not engage and stop these two horses. The armatures simply bounced out of each notch and allowed these wheels to keep turning. This caused horses two and nine to always pull ahead of the others because they would run the entire track without getting held back by the blocking arms. The solution to this problem was to disassemble the entire Drive Wheel stack and reshape every notch with a hand file as shown here.

repairing the drive wheels Upon close inspection, I noticed that all Drive Wheels had some amount of wear on their notches, so all nine wheels were reshaped by hand. I do have an indexing fixture on my milling machine, but the amount of wear in these notches did not justify the level of effort required to set up my mill. A quick hand filing of each notch was sufficient.


computer sequencer disk new brass bushing The second problem to plague this machine was that the horses would stop moving altogether, part way through the race. The Sequencer Disk was still turning but all of the stallions were stationary! Tracing the schematic revealed another circuit which includes a star shaped plastic disk and micro switch assembly inside the electronics box whose purpose is to interrupt current flow to the double stack motor and stop the horse’s movement, but only for a brief moment, about once each second. Therefore, the complete visual effect of the horse’s gallop and their jockeying for position is controlled by two separate circuits which are the Horse Blocking Relays (mentioned previously) and this star shaped disk which the schematic calls the Track Pulser. The problem of the stationary stallions during race time was due to a worn brass bushing in the center of the rack Pulser’s star shaped disk. The bushing was loose and the disk would stop turning occasionally. When stopped, this prevented power from reaching the double stack motor and none of horses would move. The original worn out bushing is shown below along with a piece of brass rod that I used for my repair. I fixed this problem by turning a new brass bushing on my lathe and applying a “straight knurl” pattern to the outside diameter of the bushing so that it would grab and hold the star shaped disk when these two pieces were pressed together. I also reshaped the outside diameter of this plastic star disk because it was not a true circle. Some of the points on the star did not actuate the micro switch.

Veeder Decade unit An interesting aspect of this machine’s operation is that the winning horse really is picked at random when the first nickel is inserted and the horses approach the starting gate. Inside the electronics box, there is a circuit that consists of two large, multi-stacked rotary switch stepping assemblies (with dozens of steps and hundreds of contact combinations) which is connected to a ten position stepping unit called a Veeder Decade (shown here). The interconnections between these three devices, is the implement by which a winner is randomly chosen. The amount of time in which this circuit is actively pulsing and picking the random winner, is determined by the energy stored in an eighty microfarad capacitor. This capacitor is used to energize the Post Time Relay. The relay supplies 110V 60Hz A.C. power to all three stepping units which causes them to rapidly pulse and advance through many different sets of contact combinations. This rapid pulsing continues until the energy in the capacitor is drained (approximately five seconds). The end result is that a random circuit path through the stepping units is chosen and decoded so that one of the nine horses (the winner) will be allowed to perform the "uninterrupted sprint" during the last quarter mile of the race. This same circuitry also causes the Odds Drum in the headboard to spin and chose new odds at the beginning of each game. An additional circuit called the Randomizer is constantly changing a resistive load that is placed across the capacitor as it supplies energy to the stepping units and the Veeder Decade. This causes the capacitor to discharge quicker in some cases and slower in others. Therefore, the stepping units will remain pulsing for different lengths of time each time a game is played. The combination of all this circuitry makes the machine a true gambling device because a winner is chosen totally at random before the player places his first bet. By the way, all of the circuitry in this game, motors, solenoids, relays and the rest, are all powered directly from the 110VAC line power. There is no voltage step down transformer in this machine, so the repair man has to be very cautious when poking around in the guts of this game.

Selection of Nixie Tubes Quarter Horse Derby Nixie Tubes The manufacturer made one particular design choice that really links this machine to the time period in which it was built. The number of coins bet on each horse is displayed on Nixie Tubes, which are miniature vacuum tubes that are filled with neon gas and ten separate "wire form" shapes. Each of these wires is formed into the shape of the numbers zero through nine and is closely stacked next to each other inside the tube. To display a number, high voltage is placed on the desired wire and it causes the neon gas around it to glow which illuminates that wire. The result is a "neon red retro-glow indication" of the amount wagered on each horse. The first picture below shows a variety of common nixie tubes. The second picture is of the nixie displays in this game.


The game designers devised a clever way to reproduce the sound of horse hoofs as their gallop around the track. Inside the electrical box, a wiper and disk assembly exists that has its contacts strategically placed so that as the wiper turns, it touches three contacts in rapid succession, then travels a short distance before touching the next group of three contacts. Each time a contact is made, current flows to a relay that is mounted under the race track. The relay is an ordinary type of relay (like the normal devices that open and close stacks of electrical contacts) except that there are no contacts, just the relay armature with one end hanging out in the breeze, attached to nothing. When the contacts on the wiper disk are made, the relay energizes and the armature pulls in to smack against the relay coil and produce a “thump” sound. By virtue of the contact spacing on the wiper disk, the relay will produce a rhythmic sound pattern of three thumps, a short pause, then three more thumps, etc. This occurs at a rate that replicates a horse’s gallop.


Quarter Horse Derby inside cabinet The electronics box and payout assembly are located in the lower cabinet, beneath the race track. Coins are dispensed from a standard hopper that is found in most ‘70s vintage slot machines. The difference between a slot machines hopper and the one in this game is the addition of two extra rotary stepping switch units, which are mounted external to the hopper itself. The first stepping unit is used to keep track of how many coins are bet on the winning horse as the player is placing his bets before the race is started. Let’s assume for a moment that when the player inserts his first nickel, horse number three is chosen as the winner and the Odds Drum is showing that horse number three will pay 8:1.

Quarter Horse Derby stepping units If the player bets his nickel on horse number three, then the first stepping unit (that I’m pointing to here) will increment one time to the first set of contacts on its wiper disk. Bets on any other horses do not increment this stepping unit, but additional coins bet on horse number three will cause this unit to advance one step for each coin. If the player bets four coins on horse number three before he starts the race, then he will be entitled to a thirty two nickel payoff (8:1 odds times 4 coins bet). All of the ‘70s style slot machine hoppers operate by incrementing a payout disk that is mounted on the side of the hopper until the correct number of coins is tallied. The hopper in this scenario would normally dispense only eight coins using its attached coin payout disk. However, the player bet four nickels on this winning horse, so the payout disk on the hopper needs to be reset and the eight coin payout process needs to be repeated three more times. That is where the second external stepping unit becomes active. Its job is to track the number of times that the hopper is reset and pays out eight coins. The second stepping unit will increment for each hopper payout and reset sequence. This continues until the position on the second stepping unit matches the position on the first stepping unit. Eight coins per payout sequence multiplied by four repetitions of that sequence equals thirty two coins.


The Article: Part 2

Kristal and Lisa Keinert After completing the repairs to Todd’s Quarter Horse Derby, it was time to start on his Kasco Untouchable arcade game. My daughters make good book ends to this machine as seen above. This machine is a ‘70s import from Japan, fashioned after a popular American TV series that aired in the early 1960s. If you look closely at the backglass, you will notice that the police car is inside a television set and that the road extends out the front side of the TV’s picture tube. The gangster’s red car is outside of the TV set as if the show is so action packed that it busts out into the surrounding area. The TV show featured Eliot Ness and his "Untouchables," a group of incorruptible federal agents that brought the infamous gangster Al Capone to justice. Coincidentally, one of my repairs involved finding a source for gangster figures to replace the missing mobsters in this game. I found a toy manufacturer that just happened to make a character whose size, shape, and criminal attire was a perfect match for this game. What does the manufacturer call this figurine? Why he’s "Al the Gangster," of course! Todd’s game is the third Untouchable that I have repaired. Besides the machine in my personal collection, I traded a second Untouchable, which I fully restored, to a fellow collector for his AMI Continental II jukebox. Detailed pictures of the Untouchable game are on my website so this article includes only a few addition photos which were taken during the repair of Todd’s machine. The game operates as follows: When a quarter is inserted, the score reels reset and the game begins, no start button exists. The playfield is actually a large treadmill with a cobblestone painted roadbed that takes up the entire viewing area. Two cars are resting on this roadbed. The red car in front is full of grisly gangsters. The "black and white" in hot pursuit contain our heroes, the “Untouchables.” Adorning the cabinet front are a steering wheel, a gas pedal, and your police pistol.

Kasco gun assembly The object of the game is to chase the bad guys through the streets of town, which is depicted on the sidewalls of the playfield area, and accumulate points by shooting the gangsters as they flee. This is a challenge because the gangster’s car does not sit still as the roadbed travels underneath. Instead, their car weaves to the lefts and bobs to the right to avoid the player’s shots. The car occasionally will remain stationary for a brief moment, but then swerve to the left or veer to the right again. The car’s randomness of motion makes it difficult to predict which way the bad guys will turn next.

Kasco robber's car control In this picture, I am pointing to the assembly that controls the weaving motion of the gangster’s car. The long vertical arm shown in this picture is connected to the bad guy’s vehicle. The combination of two different diameter gears and their connections to the vertical arm causes the gangster’s car to progress through a complex pattern of left and right motions. A micro switch that is actuated by a second cam on the smaller gear causes a "grain-of-wheat" light bulb to flash. This light bulb is described further in the next paragraph. To score a hit, the player must maneuver his cop car directly behind the bad guys and then pull the trigger of his pistol. Each shot fired by the player, is a beam of light that exits the front radiator grill of the police car.

Kasco police car This picture shows the inner chassis of the police car, its steering mechanism and the light bulb socket. If the player is skillful enough to line up the police with the gangsters when he fires a shot, the light beam hits a photo sensor mounted in the rear end of the get-away vehicle, a doorbell style buzzer rings, and ten points are scored. But wait, that’s not all… When a hit is scored, the maniacal mobster dressed in blue, sitting in the back seat of the gangster car, facing rear and wielding a Tommy Gun, will slump to the left as if he just got hit by the “G-Mans” bullet. The damage sustained is short lived however because this resilient roughneck quickly springs back to an upright position and continues his machine gun assault on the police car. His sporadic spray of Tommy Gun bullets are simulated by the occasional flashing of the grain-of-wheat light bulb that is mounted just below this mobster’s machine gun in the rear end of the get-away car. A close up picture of this light bulb and the car’s rear end can be found on my website under the "Repair and Restoration Services" link.

Keeping with true ‘70s technology, an eight track tape player emits a myriad of mobster sounds and chaos which is imposed on the innocent community as the cars race through town. The sounds include screeching tires, racing engines, grinding tranny gears, machine gun fire, breaking glass, crashing cars, and the occasional scream of a helpless female who sounds like she just got run over by the reckless renegades. The sound of shots fired from the police pistol are produced by a solid state circuit called a "white noise generator" and then superimposed over the top of the eight track sounds. All together the audio features of this machine really add to the enjoyment of game play. The gas pedal at the lower front edge of the cabinet will change the speed at which the roadbed passes beneath the cars. If the pedal is fully depressed, a circuit operates which causes the gangster’s car to move towards the cop’s car. This is accomplished by pivoting the “bob and weave” assembly (mentioned earlier) which controls the motion of the gangster’s car. The visual effect to the player is that the police are gaining on the bad guys. The player however will now be required to use even more steering skill because if his police car touches the extreme left or right sides of the playfield area, the mobsters will pull away from the cops and increase the distance between the two cars. The player needs to steer his car back into the center of the roadbed before he can gain ground on the bad guys again. The game is time limited and lasts for sixty seconds. If the player is skillful enough to accumulate the required score (settable from 300 to 700 points), then a free game is awarded and a red light comes on just below the cop’s pistol. The player simply has to press the associated replay button to start another game. Circuitry inside the headboard limits the player to one free game per quarter spent. So a sharpshooter cannot spend the entire day playing free games with a single coin and a lot of skill.


To repair this machine, I performed the usual cleaning and adjustments. A few parts however, were severely worn and required that I make new ones from scratch. The front end of the gangster’s car does not ride on its normal two front wheels. Because of the pivoting and weaving action that this car makes, a single wheel is required for the car’s front end to rest on. This wheel is hidden under the front center frame of the gangster’s car. The brass hub of the original wheel (seen in the foreground of the picture on the left) was worn to the point that it was not repairable.

police car front wheel mount police car new front wheel I turned a new brass hub on my lathe and mounted it to the car as shown in the picture on the right. Speaking of wheels, the tires on the police car were worn out and needed to be replaced. The original tires were solid black. I managed to find a diecast supplier that sells white wall tires for scale model cars. They turned out to be a good replacement for the original tires and they have the added bonus of being white walls, which dresses up the car to fit the time period perfectly. With all repairs complete, the games were wrapped up and sent back to Todd for his enjoyment.


In closing this article, I would like to make an appeal to anyone who may have additional information on the Quarter Horse Derby machine. One collector told me that he believes only fifty of these games were built and that less than fifteen exist today. I am curious to know if these facts are correct and I would like to learn more about the history of the manufacturer, Games Of Nevada. Due to the rarity of this horse racing game and the lack of information that I could find on it, I recorded a one hour long DVD video which shows the game in action and reviews many of the circuits described in this article. I gave a copy to Todd for his use during future repairs, since I doubt he wants to ship this beast 900 miles, each way, every time it needs an adjustment. I have also placed a few AVI files on my website that show the Quarter Horse Derby in action. Please feel free to contact me if you have questions or comments regarding this article, regarding my collection, or if by chance you just happen to be an NBA Star – turned Radio Color Analyst, who is looking for repair advice on those ultra rare games in your collection... -KK


Please contact me if you have any questions,
or visit my main webpage at
http://www.GameRoomRepair.com for more information.
Thanks for your visit.

arcade game animation

Kevin R. Keinert
4351 Beverly Dr.
Santa Maria, California
USA
(805) 937-8881

email animation    keinert@sbceo.org  Valid XHTML 1.1