Selector Unit Removal and Disassembly

Before I started working on this, I read all sorts of horror stories about it on the "interwebs" and jukebox forums and discussion groups, so it was with some trepidation that I approached it. But once I figured out a procedure and/or method to put it back together again, it really wasn't all that bad.

Removal of the unit consisted of following the procedures laid-out in the Instruction Manual, and among some other small things (disconnecting wiring, etc), involved removing the Carriage Assembly:

And pulling the inner shaft out far enough so that the Selector Unit could be removed as an assembly.

Notice the Popularity Counter, the Gripper Mechanism, and the Magazine Assembly remain in-place. I have to admit I was a little freaked-out by this, as I was unaware that there are two shafts involved (an inner and an outer), and I assumed that removing "The" shaft would cause the Magazine Assembly to fall-out. Sometimes it's nice to be wrong...

Once I had the assembly on the bench:

I began taking even more pictures than normal, as I wanted to be sure I did this correctly the first time. But I won't post all of them here (you're welcome!), and I'll keep it to post the more salient ones.

After splitting the assembly I noticed that two of the Clapper Coils were completely disconnected (visible here as a loose wire in the the RH assembly/part):

Which makes me wonder if this isn't what put the jukebox Out Of Service so many years ago. Regardless, I have quite a few spare parts for this assembly, as I purchased a Selector unit for a 1438 on Ebay recently, and they share many of the same pieces, Clapper Coils being one of them.

Disassembly continued with removing the blank-off pieces (not shown here), and then the "pin bank". This is the thing I had heard so much about, and was somewhat hesitant to tackle.

Dirty, nasty, greasy, disgusting.....In my opinion it's a wonder this thing even worked!

Notice the tops of the Selector Levers (shown here as somewhat pointed pieces of metal), which I will refer to in a moment. Also, notice the Selector Levers are able to move back and forth (they appears to move "up and down" here, but that's only because the assembly is lying sideways):

After removing the pin bank, one can see in this picture that there are twenty five (25) coils on the inside of each surface of the Selector Unit (only one side shown here), and these coils are, more or less, the heart of the unit.

 
Here are a couple of edge-on, close-up shots showing the contacts, and thus the beginning of how this assembly works. First of all, notice there are three contact surfaces shown in these pictures: One in the center, and two on each side (yes, those are supposed to be clean and shiny surfaces!). In this picture there are two contacts shown (shiny "plates" with semi-circular grooves in them), and these contacts are in the center position. Note how the Selector Levers (two vertical pieces of metal) are inwards, and thus the contacts do not physically connect the inner contact surface with either of the outer ones.

While in this picture the Selector Levers are outwards, and thus the contacts are outward, thus making a connection between the inner/center contact surface and both outer surfaces:

To greatly oversimplify things, the two outer contact surfaces represent the two sides of the Record Magazine, and thus each record (A side and B side). When someone makes a selection, a coil is energized (shown a couple pictures above), and that coil pulls the Selector Lever outward for that particular record, thus causing the contacts to make an electrical connection between the inner surface and the outer surface.

In turn, the Carriage Assembly (first picture in this post) rotates around the Selector Unit, and when it comes across a Selector Lever in the outer position, it "knows" it is supposed to stop there!

And since the Selector Unit (and Carriage Assembly) is directly coupled to the Magazine Assembly, the correct record may now be selected.

(Yeah, I know it's more technical than that, but for now let's just go with it, ok?)

Further disassembly of the pin bank shows just how bad the contact surfaces are:

Or rather, just how bad they "were"! But that's for the next post.