Jukeboxes, especially old ones like that absloutely amaze me! It's the logics involved in operating something like that. Today, we can easily build a little circuit board with a microprocessor, a PROM chip, a few solid state relays to control jukebox. Add a few servo motors and some solenoids controlled by the circuit board, program the thing all up, and Voila! A jukebox today is basic robotics...a high school kid could design a controller for one for a class project.
...BUT!That is today, back 50 or more years ago, Microprocessors, semiconductors and all the stuff we take for granted nowadays didn't exist!!!
Early jukeboxes like yours there are an engineering marvel. Especially for me, being only 30 years old, I don't ever remember a time when computers DIDN'T exist! A jukebox needs to accept your coins, accept and store your music selections, then operate a changer to load and play the selections stored in it's memory, and then amplify them so they can be heard. Doesn't sound like much of a job, until you look at the marvel of mechanical wizardry they used to make it all happen WITHOUT all the new fangled componets we have at our disposal nowadays. Then again, may of the washing machines we enjoy using are some really neat pieces of mechanical wizardry too!!
One thing I can say though is that modern stuff, although easy to design and put together, is much more boring! I imagine it's really fun watching all the mechanicals animation going on inside that jukebox. Things moving and spinning, sliding, swithcing and doing all sorts of other stuff while it's changing the records and playing them!
BTW, those look like 2A3 vacuum tubes in that amp. Whatever you do, make sure those things don't get damaged or fail. They will cost you about $80 or so a piece to replace!!! My Hammond Organ contains 4 of those tubes. I was going to re-tube the amp till I priced out what those things were gonna cost!!!