Explanation on Wurlitzer selector logic

[tonyj]

I was browsing the service manual for the Wurlitzer 2910 I have and have never had a grasp on how the selector works on that one.  In looking at the  wiring diagram and functional schematic, I'm a bit confused on the letter/number keys.  The diagrams seem to reference A,B,J and K for the letters, 1,5,6, and 0 for the numbers.  Not sure how the rest of them come into play and there seems to be no good description of operation like I've seen in a Rockola manual in the past.  Anyone familiar with how this works that can shed a bit of light on it?  Thanks!

[Ron Rich]

Hi Tony,
When you state "selector" here, are you asking about the "keyboard", or "pinbank" section? I don't understand what you do not understand. Here is my conception of how it works --simplified-- HTH-- The "keyboard" section sends a pulse thru it's closed number and letter switches to the correct (hopefully) coil in the "pinbank", which causes the "rocker arm to spin and lock upon a number coil and the correct letter position to "release" a spring loaded "pin". Once that's done the pin being up, closes the "over-ride" switch to start the search/lift motor.
Ron Rich

[tonyj]

Sorry - I should have specified keyboard, it's referred to as the selector in the diagram. What's confusing to me is that there are 20 number/letter keys, but on the wiring diagram, only 8 of them are called out and shown.

TonyJ

[Ron Rich]

Hi Tony,
If you look at pages 97-98, the "functional schematic", you will note that only switches numbers 1,2,9,& 0, are the only number switches shown-- On the letter side, only switches A,B, U, & V are shown. Note these go to individual coils of the same "numbers", so I ASSUME, that all of the numbers/ letters not shown, also go to their own, individual coils, and they are not shown just to "simplify" the schematic ? Ron Rich .




















aB

[tonyj]

Mine is a 2910 and uses the functional schematic on pages 103-104. It appears that there are only 20 select coils / select levers to set the pins and it shows some indexing solenoids. It appears that the assembly is rotated via these solenoids to 1 of 5 positions to get the 100 selections (pages 99-100). You are probably correct in that the diagram is simplified as the schematic on pages 101-102 doesn’t show how all the select coils connect to the key switches not referenced.