Brian,
Don't be thrown by a Test Report for the switch 'Borg Lock', inside the ship. This is one of those cases where a switch can go undisturbed for quite a while.
That single drop target seems to have suffered more than a few instances of a problem with the small coil which drops the target. It's held in a small metal frame, and moves a plate with an attachment which pushes on the target. The plate should rest against a stop, basically a part of the frame. However, this often seemed to break off, allowing the plate to move a long way from the coil, in turn leaving the the dropping 'finger' a long way from the target (it should be up quite close). Whether these breakages were due to poor-quality components or poor assembly technique (the plate is fitted to the frame, and the stop gently bent around to secure the plate/adjust the dropper) I couldn't say.
It wasn't long before these games used to be seen with the cannons out of order, parked at the 'mark' position rather than 'home', lined up with the loading outlets. The error message would be '-- Launcher Can't Find Home'. In fact, it usually could, but the wiring coming up from below the playfield was breaking down, and the optic showing the cannon was loaded was the problem - it showed an intermittent phantom ball in the launcher, causing an attempt to clear it, followed by disabling the launcher. Replacement wiring harnesses became a popular item.
The game has such a crowded switch matrix that an extra 9th column was added, it's used for the cannon Mark and Home microswitches. The Column drive comes from the small '8-driver' pcb, which is set to a mixed configuration of 6 solenoids/2 columns rather than purely 8 solenoids. Any replacement board should be set the same with some on-board jumper changes if necessary.
Even then, the spinner switch is actually an un-used flipper switch, F 7, rather than a regular switch, so it doesn't have a diode.
