AMI jukebox pulse converter overview

This is an introduction to the pulse converter selection system here used on an AMI model JAK-200.

[@sparkey1958]

nice to have you back! if you have been working on one of these, i know where you have been for the the last months! i recently restored an ami I with the same set-up...you cannot mess with the pulse genorater or receiver, i bit the bullet,stripped it right down, replaced the wipers, caps and resisters, cleaned every contact, and set it up EXACTLY as the manual in sequence, held my breath, it worked 1st time, and has been faultless since...but i agree, it is a crazy system! bob in the u.k.

[@rodrigonina9061]

hola sparkey quisiera saber donde conseguir el manual por favos? gracias saludos

[@creativetux]

Wow, amazing system. So much thought must of gone into building these, you never think what is really happening behind the scene's. Thanks for sharing and looking forward to more!

[@Trance88]

Wow! This is one heck of a jukebox. It seems extremely hi-tech for its time.

[@speter60]

I'm going to be looking at one of these for a friend, Thanks for posting!

[@vintagecoinop]

Chad great video thanks so much. I have a Ami model I 200 select and I am having serious problems getting it to make all the right selections. your video really helps. I'm really looking forward to more videos on this pulse converter so I can see how the adjustments are made your next few videos for me can't come soon enough

[@retrochad]

Hello, yes, this is done with a pulse generator behind the keyboard which consists of contacts on a circuit board which are scanned by a wiper. I will try and make another video showing it.

[@organist1982]

Good job, C! You've really been working hard on that!

[@mattkoser]

Can you explain how when you select a letter and a number, one push of the button sends the requisite number of pulses to the converter? I'm very interested in this.

[@Denvermorgan2000]

Isnt there to holes for the spring on the sprag selenoid as an adjustment?

[@MRKLITE]

You seem very knowledgeable about these machines so let me see if you can solve a mystery for me. I have a 1962 AMI Continental that works very well with one exception. It has always had problems playing any selection with the number (3) in it. In the past years I could try and select something with a (3) the the machine would just keep searching and searching. Usually after after several tries it would pick up a (3). Once it picked up the first time it would suddenly start picking up the threes on the first go around of the wipers just like other selections. After i would turn it off and try it again a day or so later it went back to the same thing, wouldn't pick up at first and then it would. Over time this problem got worse so i referred to the service manual and got out my VOM and I checked the continuity from the (3) button to the (3) segment on the wiper board and I found that the connection was good. i further checked to make sure the connection was good from the (3) segment on through the wipers to the inner ring on the circuit board and all was good. So in summary the connection seems good, all other selections seem to play perfectly but not the three. I can't figure out where to check from here. i don's know whats suppose to happen beyond those wipers to make the pin pusher work and make the selection. the manual isn't very clear to me on what happens beyond the wipers. Any advise would be appreciated.

[@alanburton6250]

I had a similar problem and cleaned the wiper board with brass polish. I also loosened the wipers and cleaned the contacts and created another problem, As it turned out the contacts and board needed cleaning but in trying to properly align the wipers after having them loose has been crazy. I mean a hair off can make a difference and you're trying to align the letter and number wipers to hit the right place in perfect sequence. Most selections play now, Ive got it close but still not on top dead center with this thing.

[@johnwendlandt6319]

I am working on an AMI I 200. Someone has taken apart the converter, and I think the wipers are not adjusted correctly. I am not sure how do do that. I do have the manual.

[@kencekosh2127]

it explains it in the manual. very easy!

[@sweeper91169]

Most common problem in the pulse converter is corrosion on the circuit board (both sides) which prevents the rotating contacts from making a good circuit, bent rotating contacts (somebody tried to fix it by bending something), or misadjusted rotating contacts, usually on the stepper side. I think most of this circuitry is operated by the 24-volt DC power supply in the upper part of the cabinet; if the capacitor is bad, you won't have the full 24 volts required to make everything work. I fixed two of these jukeboxes that were stored in an unheated warehouse for over 20 years; cleaned a LOT of contacts! Got both of them working, but one later developed a problem of selecting the wrong record (B1 instead of A1, for instance). Found that someone had adjusted the stepper contacts on the "letter" side and had not tightened the setscrew up after adjusting. Lined them back up, and everything worked. One other note - the pulse generator actually sends a couple of "dummy" pulses before actually sending the "letter" information. If you watch this video when he shows the "letter" stepper and selects A1, you can see that the stepper actually moves more than one time. Had one other troublesome problem - unit would occasionally blow one of the cartridge fuses for no apparent reason - could not find a short. On an obscure page of the service manual, reference is made that the unit should use "slow-blow" fuses - this is not marked on the power supply. Put slow-blow fuses in; no further problems. DE

[@ΔημητρηςΤσατσαρωνης-θ2τ]

Hello, I have the same machine and my problem is that the selection is made correctly but after this nothing happens no disk movement. Can you help me ?

[@Zylstra555]

Hi Chad, I really enjoyed this video. I wish I could see this in person! What year is this jukebox?

[@vintagecoinop]

Great video chad this video is a huge help

[@Raedlifuxer]

That would be great. I am also very interested in this pulse generator thing 8-)

[@MetaphysicalEngineer]

Very, very cool stuff!

[@mindelynkuntz8493]

I have a rowe ami mm6 silver sage. i bought from a private owner it played before i moved it got it home plugged it up played it then the arm got lodged and after i freed it it will no longer recognize me pushing the buttons/number to pick a 45 to play we can do it manually by turning the piece with an allen wrench on the left side and also by pushing down on the button type solenoid on the right side any ideas on a fix for this?

[@alanburton6250]

Hoping to get some advise on adjusting the contact wipers on an AMI Continental. At one point I had to take clean the contacts but I have been unable to properly align the wipers. A couple of times I it way off, for instance I would push A5 and it would play D5. Fortunately I was able to get it back to where it plays most selections. The only ones it won't lock on is A and B numbers 7 thru 10 and J and K 7-10. It plays all selections on letters C thru I. One problem I have is when I try to adjust the wipers the record drum moves on me making it more difficult. How can I lock the record drum on A-1 and get it to stay there while I make an adjustment. I mean it's crazy a hundredths of an inch can make the difference. Any suggestion appreciated

[@retrochad]

Thank you, I think this is a 1960 model.

[@Tron1731]

it really looks dry try some teflon oil that wont dry out a drumal and polish the contacts the unit also looks dirty, dirt is the issue allways start a job clean like that intake allways power wash everything before u work on a car u dont want any dirt to get on the clean surface areas that u are sealing up i can see dirt inside of the machine lots of dirt and dust also run the unit when applying oil to the parts can hear grinding somthing is missing a bearing ?

[@RetroVintageItems27]

Great video chad!

[@SeeburgMusic]

The problem is your power supply is sagging. Replace the capacitors in that along with the selenium rectifier and your problem will be solved as long as all of your wipers and contacts are clean and everything is adjusted correctly.

[@koioo2]

hi chad

[@TheMultiGunMan]

★★★★★