[Jukebox-list] AMI PUSHBUTTON QUESTION

[Steve Wahl]

On Mon, May 14, 2007 at 10:25:29PM -0400, Dan Peshkin wrote:
> As you all probably know I am a novice to the world of jukeboxes.  I  
> am in the process of getting an AMI F-120 going.  I received my  
> manual but am still having a couple of problems.
> The credit unit seems to be operational but I do not have a slug  
> rejector/coin mechanism present in the machine.  It seems to work on  
> free play , although the manual makes no mention of how to set up the  
> machine for free play without coins.  

Free play is a recent invention; it served no purpose whatsoever when
the manual was written!

> I have an intermittent problem where the pushbuttons work for all
> 120 selections....but sometimes when I turn the machine on, only the
> first column (farthest left) of push buttons will work and the
> remaining will not.  I can not trace the cause.  I have a feeling
> that it has to do with the credit unit.  I realize that the wiring
> to the push buttons in in a series, but it makes no sense to me why
> one column of buttons works and the rest will not.

This is almost certainly a continuity problem from one row to the
next.  That follows because the credit unit is common to all the
switches, and cannot "tell" which ones you are pressing so that it
could act differently; the series circuit is practically the only
thing that is common to large portions of the selections, such that it
could take out a large number of selections without taking them all.

The one thing to know is that the continuity does travel from one
button to the next, but does not go in numerical selection order.  I
just went and looked at my F.  If you number the column buttons with 1
at the left, the pattern seems to go up (bottom to top) first column,
then bottom to top on the third column, then top to bottom on the
second column, and (probably) bottom to top on fifth column, then top
to bottom on fourth column, and so on.

I say probably, because I only looked at the first three columns.  In
terms of selection numbers, the circuit travels from 12 to 11, 10, 9,
... 1, 36, 35, 34 ... 25, 13, 14, ... 24, and so on.

[I just thought of this: Hopefully you've figured out that you can
undo a couple of latches and tilt the whole title/button assembly out
forward?  If you're leaning in through the main window to see the back
sides of the buttons, that's the HARD way!]

If indeed selection 1 works but 36 doesn't, clean the normally closed
contact on button 1 (meaning the contacts that touch when the button
is NOT pressed) by pushing the button, inserting a piece of paper or
business card between the contacts, letting go of the button, and
pulling the paper back out).  

If it's not 1 working but 36 not, follow the buttons through until you
find the "first" one that doesn't work, and figure out which one is
previous, and clean that.

Hope that helps!

BTW, there is another thing that can "take out" banks of selections,
but doesn't seem to match your symptoms.  The selection levers are in
3 blocks of 40 levers (actually, 6 x 20 if you take it apart far
enough to look at it).  Any lever selected pushes up on a bail that
goes across a group of 20 levers, and these bails are mechanically
connected to a leaf switch that starts the mechanism when there's a
selection it hasn't yet played.  The leftmost 40 selections (first
"section") are tied to one leaf switch, and the other 80 (second and
third sections) are tied to another.  

My F120 would originally only run if a selection in the first 40 was
selected, but it would pick up selections in the other 80 if it passed
them along the way.  This was of course because the right-side leaf
switch wasn't being actuated by the bails; I had to bend -- execuse me
-- "reform" the lever that was supposed to make this happen, and after
that it worked nicely...

--> Steve Wahl

-- 
Steve Wahl    steve at pro-ns.net

Fools ignore complexity.  Pragmatists suffer it.
Some can avoid it.  Geniuses remove it.
-- Perlis's Programming Proverb #58, SIGPLAN Notices, Sept.  1982