Small capacitor on Bally SS pop bumper switch, necessary ?

[DRD]

Cleaning up my pop bumpers today, I saw that one capacitor was broken off from the solder on the leaf switch. You might just see it here in green ...



So I soldered it back on. Now I get a switch error when I run the tests so the pinball thinks this switch is permanently closed, and it stops the pop bumper working.

It may be a previous owner just disconnected it. Am I best just to disconnect it, and forget about it - or is the troublesome little thing important ?

The game works fine without it, so as of now it is disconnected again

Thank you

 

[kevlar]

I bought a few off Jim last week. Not sure how essential they are but I intend to fit one to a switch on my Centaur which seems fine yet doesn't always work.

 

[Sgt GrizZ]

From http://homepinballrepair.com/#SSswitch




Capacitors
Capacitors were used, primarily, on early Bally and Stern SS pins. Capacitors are there for a purpose. Some switches, such as targets get hit so briefly that the computer does not register them. The capacitor helps to simulate a longer hit so that the computer can register the points.

However, there is a downside. Caps can pick up electrical noise, such as a solenoid firing and send a signal to the computer giving a false switch hit.

That said, Bally especially went overboard installing caps where they are not needed. Some think they are not needed on roll over switches, although it is possible for a ball to fly through a lane and not register. Drop targets never need them. Targets usually need capacitors.

If a switch appears as stuck 'on', yet inspection indicates that the switch is not closed and it has a capacitor across the switch, try removing the capacitor. Removing it may fix the short or stuck on switch. Try playing the game. If the switch registers properly, you can leave the capacitor off.
However, it may not always register properly. If you find that the ball hits the switch and the points are not always registered (the 8-ball target on Bally Eight Ball is an example), then install a new capacitor.

 

[DRD]

Thanks @GrizZ. Just the job

 

[*paulb*]

I had horrible intermittent faults on my Fathom thanks to a faulty cap on a bottom return lane. Of course those caps are not on the playfield schematic - so I assumed it couldn't possibly be a switch capactior fault - started thinking it was an MPU issue. Clipped off the caps on both sides now.

 

[Johnnyo]

They do make a difference had intermittent faults on my old bally particularly rollovers and stand up targets swapped out or replaced missing ones. machine was much more stable after that with registration of switches.