The step-by-step, mechanical logic of old pinball machines

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[LakeNipissing]

Alec, make sure the ball plunger soft tip is in good shape. Once the rubber wears too thin, the ball gets pitted / dented and the playfield artwork will get scratched and worn by the ball. Playfield wax helps a bit, but make sure the ball is perfectly smooth and the plunger tip is decent. They are cheap compared with the damage that can occur to to the playfield artwork.

[sirmongoose]

I had a wife before this channel, a family. I gave them up so I could keep watching this step-by-step logic of pinball machines and technology videos.
They simply got in the way.

[heyspookyboogie]

It boggles my mind the amount of work it must have taken to dissect this machine and its schematics, figure out where everything is irl vs the circuit diagram, and build a whole script to actually explain it to general viewers and film it all to demonstrate it.

We’re clearly not in no effort November anymore.

[kiligir]

This has the energy of "I had to look at this schematic for days and now you have to as well." And because it's Alec, you bet your pinballs I'm going to watch it all.

[Codexionyx]

It's videos like yours that have made me appreciate just how incredibly clever, complex, and elegant technologies and systems that seem "old fashioned" truly are. It feels like a common misconception that people were somehow less smart in those days when they were anything but.

[lordmemester]

The fact that the captions were raised at a few points so as not to block some of the visual details made my day. Thank you.

[champs]

With all the relays, contacts, and bulbs with very real limited lifespans, it's pretty amazing that these things actually worked well enough and long enough to make any money for the owner at all.

[davidhittner]

My parents got us a "home" version of the AZTEC machine from a local pinball distributor. The home version was modified to add a push button that would add players rather than having to insert coins. The machine was delivered with all schematics. It was serviced by the distributor as needed until I was old enough to assume the care and feeding of the machine. Alec, if you didn't know it, if you flip the power switch off and back on quickly when the last ball of the last player went out of play and the machine had not yet finished counting down the last points, it would finish counting down and then give a free ball. Infinite balls if you did it correctly. Enjoy. :-)

[barrell]

I was an industrial electrician before I retired. I cut my teeth on relay logic programming and troubleshooting, needless to say I had to go through complex schematica on a daily basis. These pinball videos take me back to my early years before the machinery I worked on were controlled by PLCs. Your explination on relay logic operation is spot on.

[dadahlberg]

"2 bits of trivia, " immediately following the discussion of the quarter mechanism, was an awesome dad joke. nicely done!

[MichaelPiz]

Re: stepper motors

Back in the mid-80s, I was working for what was then AT&T Microelectronics. At our plant, we made microchips and I worked in the chip testing department.

Chips were manufactured thus: the circuits for a number of chips were etched onto thin silicon wafers, about the size and shape of a DVD. The chips were then tested on the wafers in machines that would spin the wafer to set each chip into position for very thin probes to contact it and run various inputs into and take outputs from the chip. The wafers were then literally sawed apart into individual chips, which were placed into their familiar centipede-looking "packages", then tested again in the packages before being shipped out.

At some point, the plan was to also have bar codes etched into the wafers for inventory tracking. Bar code readers were fit to the testing machines for this purpose. But the bar codes consistently failed to scan properly. It didn't take long to figure out why: the machines used stepper motors to position the wafers for the probes but stepper motors are lousy at the smooth rotation required for reading bar codes. Panic ensued. (Well, people got kinda worked up about it, anyway.)

Then my cubicle mate, Dave, a great and very smart guy, found a solution. He researched a mathematical formula that produced a sinusoidal curve which, if cut into a drive shaft, provided perfectly smooth, uniform back and forth motion for a pin riding in the groove. What made the formula unique was that there was no acceleration/deceleration at either end of the shaft, which was necessary for proper reading of the bar codes. He designed a small motor with this shaft/pin configuration, which could be mounted on a test machine to spin the wafer independently of the stepper motor to correctly read the bar code.

This ingenious solution got Dave a patent. It was very cool.

[tookitogo]

19:39 The fact that it’s split 8-12 and not 10-10 is likely another artifact of the original design having 16 reels: it would have been 8-8. When they tacked on another reel to each bank, they just paralleled it up with one of the banks, because redesigning it to do a 10-10 split would have been a much larger architectural change.

[spaszek]

hey alec, if you’d ever like to do a video regarding automatic pinsetters in bowling centers, let me know and i’d love to help and even invite you to my center in metro detroit. AMF machines are electromechanical entertainment at a borderline industrial size. many of the electrical stuff on my machines have been converted to integrated circuit boards, but there’s still machines near me running off steppers and relays such as these. there’s an entire center as well in iowa i think that runs Entirely off steppers and relays and still retains all of the original functionality.

[eagleburger]

My Dad bought a Bally Wizard for our house when I was in highschool. I always remember opening up the cabinet and seeing that mess of wires underneath it, wondering how the heck it worked - especially how it could tell if you had the double bonus lit and award you double points when the ball went out of play.

Thanks for scratching a decades long mental itch!

[mynameisbone]

TC is always remarkable with their captions. At 19:30, the captions were even bumped up so you could see the subject in action! Thank you so much for making good captions.

[CSD-CSD]

Another great educational video! However, using this pinball machine for educational purposes violates its clear and centrally stated "For Amusement Only" directive. Per pinball law your fine must be paid in quarters.

[danoconnell]

I worked in a shop cleaning and repairing these machines in the '70s, and I am blown away by your detailed knowledge and clear explanations. Damn, man. You're the best!

[JDfromWitness]

Congratulations! Back in the 1970s, I worked for an amusement and vending company and had to learn all of this. In watching your video, I can easily state that you are far better at explaining the operations of E/M machines than any of our instructors/co-workers. (who would usually tell me to just lay the schematic out on the floor and "figure it out") Yes, finally got good at it, but a video like this would have been worth it's weight in gold back then. (which would have been a lot as it would have to have been on 2 inch quad R-R tape!)

[LakeNipissing]

Mechanical "memory" in these EM pinball machines is really complex... and amazing.
You have done an excellent job explaining all of this... the 6 foot long schematic for these machines is insane.
This is a great resource for me, since I have a Williams 4 player EM machine from 1977, _Argosy._ Very similar schematic and functionality, with different playfield and backglass. Thanks again!

[pomonabill]

Just fascinating what was done before micro processors were used for these games!
Of course, part of the fun was the noise the relays, steppers, solenoids and motors made.
Thanks for the detailed explanation!