Deltronic Test Fixture for Skee-Ball Model H

Author: Wayne Eggert
Date: 3/14/2012

Introduction
Sometime in the mid to late 80s while Deltronic was producing the Model H for Skee-Ball, they also offered a "Skee Ball Alley Simulator" as one of their products.  I don't have many details about this device other than what's seen in the pictures.  This showed up on an eBay auction in 2011 and sold for $316, which seems like a pretty good price for it (wishing I bid higher!).

I plan to add some more information here if I can get further details from Deltronic Labs, Inc.

Photo: Deltronic Test Fixture - Top
Image from eBay Auction

What Is It?  Who Used This Device?
This device would assist someone in testing a Model H Skee-Ball MPU board on the bench (ie. would not need the alley to diagnose / repair the board).  It was likely used by individuals at Deltronic Labs, Inc. and/or Skee-Ball when customers would send problematic boards back for repair.  It may also have been a product made available to operators, but generally operators weren't repairing boards to that level so until I get confirmation one way or the other all that can be said is this product would have been useful to major operators of Skee-Ball machines.

More Pictures / Observations
Just going by the pictures, we see that there are several push buttons..

• coin 1
• coin 2
• balls released
• score
• reset
• balls played

Pushing these buttons would have simulated various functions on the alley like inserting a coin or scoring points.  A ticket dispenser could also be hooked into this simulator to verify dispensing of tickets or diagnose ticket dispenser PCB boards.

There is also a full scoring and ball-count display integrated into the tester.  This wouldn't verify the score display in the machine being tested, but it would help isolate whether there were issues with the score data the MPU board was sending the display.  There are also lights to simulate the game over, winner lights, free game & beacon (flasher).  Lastly there is a light indicator for "solenoid" which would visually show the circuitry involved in the solenoid circuit was being activated by the MPU board.

Photo: Deltronic Test Fixture - Serial # / Model Info
Image from eBay Auction

The alley simulator would have been used on Model H alleys, however it may be possible that it was also used for Model S alleys.  Some of the wire harnesses would have been different on the Model S, but the functionality of this test fixture should theoretically have worked for the Model S.

Photo: Deltronic Test Fixture - Cables
Image from eBay Auction

Summary / Thoughts
To be sure, this test fixture would have saved a lot of time when diagnosing a faulty Skee-Ball Model H board and useful in a repair facility.  It also seems to be pretty uncommon.  The eBay auction was the only time I've seen mention of the device.  It's fairly simple in its functionality, there's not really any actual diagnostic stuff happening (verification of memory, CPU addresses, etc) -- but it's very likely it helped assist with the most common faults & a logic probe / scope could be used on the bench for further diagnosing.  The biggest advantage of this device would have been to have an easy way to hook up a Model H MPU board on the bench instead of having rats nests of alligator clips &/or having to take the MPU board to the full-size alley every time a repair was made.  Pretty neat stuff, and a piece of Skee-Ball history!