Rock Ola 460 selection problem

I'm trying to get a Rock Ola 460 up an running again.
The selection of a number is not working as it should.
When entering the digits in the keyboard, the lights indicating first digit, second digit, wrong selection, ... are working as they should, so I don't think there something wrong in the keyboard itself.
If the third digit is 1,2,3,4,5,6,7 nothing further is happening. The only thing I can do is pushing the reset button, to make another choice.
If the third digit is 0, the selection arm is rotating to the correct position, but the "write-in" action itself is not happening. Both relays (stop and write) in the red transparant plastic housing are switching at that moment. Pushing the reset button, is not possible when the third digit is 0.
On the control PCB (the one where wiring from keyboard is going to and from where a bundle of wires is going to the write in/read out disk), I have checked all diodes. They are still OK to my opinion.

Is anyone having an idea what can causing this issue?

On 5/18/2011 3:57 PM, Luc_from_Belgium wrote:
I'm trying to get a Rock Ola 460 up an running again.
The selection of a number is not working as it should.
When entering the digits in the keyboard, the lights indicating first
digit, second digit, wrong selection, ... are working as they should, so
I don't think there something wrong in the keyboard itself.
If the third digit is 1,2,3,4,5,6,7 nothing further is happening. The
only thing I can do is pushing the reset button, to make another
choice.
If the third digit is 0, the selection arm is rotating to the correct
position, but the "write-in" action itself is not happening. Both relays
(stop and write) in the red transparant plastic housing are switching at
that moment. Pushing the reset button, is not possible when the third
digit is 0.
On the control PCB (the one where wiring from keyboard is going to and
from where a bundle of wires is going to the write in/read out disk), I
have checked all diodes. They are still OK to my opinion.

Is anyone having an idea what can causing this issue?


Sounds like the pushbutton assembly. Often if parts of it our out of
adjustment, the buttons on one far side will either work or not work.
Try holding in the last button to see if it selects. Also the button
contacts that are in series can be dirty and/or in bad condition. Some
of these can be jumpered from each switch to the next instead of all of
them in series, that is if it's for home use anyway. Of course the
mechanical parts of the assembly and it's contacts are prime suspects also.