The new Pinball Test Unit (PTU) from Dave’s Think Tank improves tremendously on the self-tests of any pinball running a Bally AS-2518-17, AS-2518-35, Stern MPU-100, Stern MPU-200, or Alltek replacement MPU board.
What kind of improvements are we talking about? Instead of just running through the solenoids over and over, the solenoid test now allows you to stop on and repeatedly fire a single solenoid, then stop it from firing while you make adjustments, then start it up again. It will tell you if vibration from a solenoid is setting off a switch. Similar improvements can be found in all the tests: the light test can review dimming features, bouncing switches can be found and tested, and even switch matrix errors just became a breeze! Not to mention new tests like the DIP switch review. Check out the new and extended tests below:
The first test will repeatedly flash all the switched illumination lights on the playfield and in the backbox. This is similar to the regular Bally light test, except the PTU allows you to now press a button to stop all the lights from flashing except one. Then you can scroll through the lights individually. Press another button and you can go through all the dimming levels available.
So why would you want to do this? Well, maybe you just find it easier to work on a light when the whole machine isn’t blinking at you! In some machines, these light switches control not just lights, but also switched relays, and it can be important to find them, especially if they're not working! You can also make up a numbered list of lights, making it easier to locate problems in the future. A numbered list is essential if you intend to do any Arduino programming of your own. There are lots of advantages to expanding this test!
Pressing the self-test button again will then take you to the display test. The first difference you’ll probably notice is, it’s a lot faster than the standard display test! Every digit gets through the numbers from 0 to 9 in 2 and a half seconds, instead of what used to seem like 2 and a half minutes. Trying to watch five displays of six or seven digits, each taking about 10 seconds to complete was always a tedious process.
To make it easier though, you can press a button. Now you can watch one digit at a time going through its paces without distraction. Hold in the switch, and you can scroll to the digit you’re interested in. Scroll to the end and all the digits scroll again.
Another new feature does away with the scrolling numbers, and sets all digits to the number 8. This lights up all the segments of the digits, and makes it easy to assess dim, missing, or burnt segments.
Pressing the self-test button again takes you to the solenoid test. This runs through all the solenoids, just like the regular Bally test (except in a different order). This latest version also includes the Coin Door Lockout and the K1 Flipper Relay.
New Features:
Pressing the primary switch at any point will cause the current solenoid to continue firing repeatedly, so you no longer have to cycle through all of the solenoids to see the one you are interested in. Press again to continue cycling. Press the secondary switch to turn firing of solenoids off, and back on. This allows you to both observe and work on a solenoid while remaining in test mode!
Keep an eye on the credit window during this test. If vibration from a solenoid causes a switch to misfire, the switch number will be displayed here. The time between the solenoid firing and the switch activation is shown in display #4 (in milliseconds). This makes it easy to determine the solenoid and the switch involved, and to fix the problem!
Pressing the self-test again takes you to the switch test. Switches that are stuck on will be identified by number in the displays, like the original test. However, the PTU allows up to four stuck switches to be identified on four displays. The original Bally test displayed only the lowest-numbered stuck switch, making testing of multiple stuck switches and switch-matrix issues difficult. The number of closed switches is also displayed in the Credit display, for cases where more than four switches are closed at once.
Double-clicking the primary switch will activate and reset any solenoids you specify. This allows you to easily test and work with drop targets and other tricky switches, and then quickly and easily reset them.
The Stuck Switch test can also be used to locate switch matrix issues. The 40 switches of a pinball are wired together in an 8x5 grid. Diodes on each switch make sure one switch closing cannot affect any other switch, but a bad diode can cause problems. If a closed switch has a bad diode, and another switch in the same row is closed, and another in the same column is closed, then a fourth switch at the opposite intersection of the row and column will also register as closed. With the PTU able to show four closed switches, testing for switch matrix issues just became a whole lot easier!
Pressing the self-test button again takes you to the switch bounce test. Switches on your pinball machine may develop a “bounce”, where hitting them registers two or more hits. If you suspect this may be happening with a switch on your machine, this test can help you to identify the issue.
To determine whether a switch is bouncing, activate the suspected switch with a pinball. If it registers only once, the switch number will appear in the Player 1 display, and all other displays will be blank. If it registers two or more times, the time between hits will appear in the Player 2 display (measured in milliseconds).
Pressing self-test again takes you to the sound test. The original Bally test simply played a single sound. The PTU cycles through all the sounds. Pressing the primary switch plays the current sound repeatedly. Pressing it again will continue cycling sounds.
Display #1 will indicate the sound number to be played. If the primary switch is pressed within one second of the display changing, the current sound will be skipped. Holding the button will increase speed, skipping sounds.
The sound test currently only works with Bally Squawk & Talk boards, or their equivalents, such as the Geeteoh replacement boards, or a WAV Trigger board. It also does not work with the very early Bally Sound Module boards, or their Geeteoh replacements, on games like the 1979 Bally Star Trek.
Pressing self-test again takes you to the DIP switch test. This completely new test shows you the setting of all 32 DIP switches, and allows you to change them temporarily. Turning the machine off and on again restores the DIP switches to the settings on the MPU board.
All 32 DIP switches are shown in the display digits as either 1 (ON) or 0 (OFF).
By pressing the primary switch, you can scroll through switches 1 to 32. Stop on a switch and you can use the secondary switch to change its setting temporarily.
This can be useful to detect defective DIP switches, or just to review the DIP settings without having to open the backbox.