TECH: STNG Switch Matrix, Right return prox sensor tripping optos

[Matt Young]

Hi folks -

I just looked through the archives and found someone who had the very
same problem I have with my STNG, and of course LTG offered suggestions,
but there wasn't a solution posted. The problem is this:

Rolling a ball over the right return prox sensor causes the Trough Out
and Under Borg optos to trip. (Right Prox sensor is sw. 17, Under Borg
Opto is 37, and Trough Out Opto is 47) -- all on the same row. Sw. 27
(Right lower bank center) is unaffected, neither are switches 57, 67, or
77. If I unplug the power to the opto board, the Trough Opto still
trips. Likewise, with the trough boards unplugged, the borg opto still
trips when rolling over the right prox sensor.

I've checked the orientation of the diodes and wires on the relevant
switches, and looked for shorts, but the lack of sw. 27 firing makes me
think it may not be a diode or wiring problem.

Anyone have some more ideas for me? Especially if you post as
"Louseman" and remember the solution (or did I just buy your game
because it's unsolvable? :))

Thanks a lot,
Matt

[Matt Young]

A little more googling found my answer, so posting here for the archive:

The white/violet wire was on the wrong lug of the drop target switch...
a quick move of that and the problem is gone.

Thanks for reading!
Matt

Matt Young wrote:
> Hi folks -
>
> I just looked through the archives and found someone who had the very
> same problem I have with my STNG, and of course LTG offered suggestions,
> but there wasn't a solution posted. The problem is this:
>
> Rolling a ball over the right return prox sensor causes the Trough Out
> and Under Borg optos to trip. (Right Prox sensor is sw. 17, Under Borg
> Opto is 37, and Trough Out Opto is 47) -- all on the same row. Sw. 27
> (Right lower bank center) is unaffected, neither are switches 57, 67, or
> 77. If I unplug the power to the opto board, the Trough Opto still
> trips. Likewise, with the trough boards unplugged, the borg opto still
> trips when rolling over the right prox sensor.
>
> I've checked the orientation of the diodes and wires on the relevant
> switches, and looked for shorts, but the lack of sw. 27 firing makes me
> think it may not be a diode or wiring problem.
>
> Anyone have some more ideas for me? Especially if you post as
> "Louseman" and remember the solution (or did I just buy your game
> because it's unsolvable? :))
>
> Thanks a lot,
> Matt