Jukebox Electromechanical Automation Explained

If you ever been curious how old-school jukeboxes work, it’s all electromechanical and no computers. In a pair of videos, [Technology Connections] takes us through a detailed dive into the operation of a 1970 Wurlitzer Statesman model 3400 that he bought with his allowance when he was in middle school. This box can play records at either 33-1/3 or 45 RPM from a carousel of 100 discs, therefore having a selection of 200 songs. This would have been one of the later models, as Wurlitzer’s jukebox business was in decline and they sold the business in 1973.

This may be the ugliest jukebox ever produced.

This jukebox is actually what turned me into the weirdo that I am today.

External appearances aside, it’s the innards of this mechanical wonder that steal the show. The mechanism is known as the Wurlamatic, invented by Frank B. Lumney and Ronald P. Eberhardt in 1967. Check out the patent US3690680A document for some wonderful diagrams and schematics that are artwork unto themselves.

[Technology Connections] explains how the whole thing works, and your brain will be spinning when he’s done. It’s amazing how everything is precisely orchestrated, and even more amazing that people were able to maintain and troubleshoot these contraptions. He says there may be a third installment, so stay tuned. If you like these things, check out this writeup we did about a restoration of a diner table-top Seeburg jukebox back in 2018. Have you ever worked on one of these electromechanical sequencers? If so, tell us about it in the comments below.

19 thoughts on “Jukebox Electromechanical Automation Explained

  1. My boss got a Seeburg jukebox. I cleaned it up and outside of an amplifier problem it worked. Then something got sticky and I could free it from being sticky with solvent lube and a sore fingering to free a gear. It worked fine till it kept cycling. Load, start play and change out the record all in one step. I stopped because that baby Borg of a mechanism gummed up needing an ultrasonic bath in solvent. Only one solenoid initiated the sequence of changing the record, but what a sequence it ran. All done mechanically, no programed pulses from electronics.

    It had tally wheels counting the number of past plays for each record. ASCAP! The memory of what to play was in the hands of magnetic toroid memory and few tubes. No cams or movable tabs. It worked perfectly. The most outstanding feature of this machine was stereo sound, about a year and a half after stereo came out on vinyl. Jukeboxes are so retarded now. I remember seeing one of these Seeburgs back in 1959. 2 speaker grilles marked channel one and channel two.

  2. “and even more amazing that people were able to maintain and troubleshoot these contraptions”

    I guess that is exactly what an old jukebox service engineer might think when they see a modern computer… then turns away and thinks “at least in a jukebox you can follow the path and visually diagnose without special tools, silly modern black boxes called computers, ha, you can’t even fix them with a screwdriver and they don’t even supply schematics”.

    Sure an old jukebox is impressive to look at and I love every bit of it. But complexity is just a matter of perspective. So please, don’t call them “contraptions”.

  3. This is awesome! It reminds me of the old, electromechanical slot machines. I lived with a guy in the Vegas area who had one just sitting around, so we took the innards out to see how they accomplished randomization and maintained a beneficial (to the house) payout ratio. It’s really innovative!

    Having seen it, I really don’t recommend trying to beat them or their updated counterparts.

  4. I still use mechanical systems for controls. I have a video master control switcher at work that needed to communicate to an external device for the start and stop of an event. Problem is the switcher only did a tally voltage when the event was running, but I needed to provide momentary pulses on start/stop.

    Relays to the rescue.

  5. I don’t know why exactly, but the second video posted above really makes me happy. It is explained so well, and with just the right amount of humor. Wonderful. I am in awe at the design competence from this era of mechanical devices. Simply amazing.

  6. Wurlitzer, Seeburg, AMI all started out making coin operated pianos. Mills novelty also made coin operated instruments before Jukeboxew. If you want to see amazing mechanical engineering from the early 1900s, search for Mills Violano

  7. I recently picked up a 1939 Wurlitzer 600A that I am restoring. I marvel at how much they were able to accomplish by mechanical means where we now rely on computers. The same goes for mechanical era pinball machines and office adding machines. They are a pleasure to work on!

  8. There’s still a lot of interest in jukeboxes.

    Earlier this year I got an AMI/Rowe 1971 MM5 Presidential working – the last time it was known to work was in 1989. I don’t think I’ll ever get tired of watching it do its stuff.

  9. Repairing old electromechanical jukeboxes is easy , i have done this all of my life , the old ones are far more reliable than any newer computerized one , when they are properly serviced. Biggest issues being lubrication and dirty contacts , i have over 200 jukeboxes in my collection and work on restoring them every day

    1. I wish you were close by, I have an old seburg that I dont know what to do with.
      Its complete but it will not work, when I first got it, it would not select the record it would just keep searching, once in a while it would choose a record.
      So I did some research and it said you can remove the carige from the machine and use a degreaser and water to clean it. ( plus my wife did not want it in the house it smelled like cigarettes)
      Well after cleaning and waiting over a month to let it dry, I reinstalled the carige turned in on, the carousel traveled to the left, got jamed and then I noticed smoke comming from the big transformer, I unplugged it right away, and its been like this for the last 10 years.

      I’m not sure what to do. My wife wants me to bring it to the land fill, I’d like to try and repair once more,
      This week end I will remove the carige once more.

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