What else does it go to up above?

Are you sure? Seems play field is still alive in case a ball is in a kickout hole.

I'm not going to strain my eyes with you schematic, but beside that switch on the tilt relay, how is power cut to the score reels or relays?

See this schematic fragment

Changes from the schematic could confuse maintainers going forward and I haven't heard of that being a problem. Has anyone?

Pinball (resized).png

I see said the blind man.

If so it wouldn't be the first time they have used redundancy or switches that are pretty useless like that left lane rollover on Grand Prix.

Switch guarantees that no extra points are awarded. In 4p games, score is everything. Tilt disqualifies ball.

All depends on what state the machine is in when the game tilts. Most of the time it'll be fine. Sometimes, there's a chance that the relay losing power will be in the process of moving the reel.

Maybe to keep bonus points from registering after a tilt? This is basically what "bingopodcast" said above.

You're saying that coils could potentially burn up because they wouldn't be de-energized by the EOS switch on the reel unit?

Sounds like the pinball equivalent of Chernobyl! Why don't you run a non-destructive test, simulating that scenario. Of course, intervene before smoke and flames occur!

So it's just a matter of tying together the two leads on that one switch, correct?
I don't have any of these games, so it's a non-issue for me. My friend has a "Space Mission", but it's currently not operational anyway.

If you're not interested in others' opinions don't ask questions!

Wait, just looked up the schematic... how? You have multiple switches in the tilt relay misadjusted for this to happen.

P.S. Have you tried adjusting it properly?

Why would that cause a problem? The game doesn't care about the position of the reels... (mostly).

Oh, yeah! (burn) Well, here's a question for you: where does that other switch pair sink to, and what happens when you have power jumped to it?

Hi NicoVolta +
I opt for the "boot to the head" --- a statement of deeeep insight: "In a fully running pin: Everything works fine" --- end of joking.

Thanks for looking up in earlier schematics. I also say "laziness (or: NOT realizing)" - stuff working good in earlier pins is kept in newer pins - even when no longer needed - actually when may causing problems. I see bingopodcast 's point --- "wired as is - as shown in the schematics": A Score-Drum is busy pulling-in the plunger to then give point(s): "Wired as is cuts power to the Score-Drum-Coil a bit earlyer compared with: Frst the points-RELAY must be made non-operable - this then cuts power to the coil on the Score-Drum" - bingopodcast 's point is true - I assume we talk about 0.01 to 0.02 seconds time-difference.

I also say: Connecting "yellow to white-orange on the M&B-Switch" --- please: Solder-on a short wire and put a tag on this wire to tell about --- do not: Heavy*** bending*** the switch-blade-white-orange so it always has connection to the middle blade.

Heavy*** bending***: I learned that some people do heavy*** bending*** a switchblade when they change a pin to "Free-Play" - I think: Also (there) a wire should be used. Greetings Rolf

I don't think so...
I'm talking about Grey-Blue 3. This is the opposite side of the SPDT of the tilt switch in question. This is the third use of that wire in the schematic - they are not connected to the other two uses.

Where does that wire go? You're switching the common under that section. Has to go somewhere. The answer likely lies in that switch.

I agree with not heavily bending and tagging the wire as a mod. Makes it easier to adjust properly later.

Nope, I'm workin'. But you have the game and a meter. I will suggest that it runs through a JP since it has to reach back up to that panel - look near the other switch on the female side of the plugs. It might change color through the plug.

Regardless, they wouldn't have put in a SPDT switch (and wired it) unless that other side was doing something. As with most SPDT switches, they don't expect BOTH sides to make contact at once with the traveling leaf. Not pushing to /dev/null. It's going somewhere.

Hi NicoVolta
You say "the answer eludes me - find it ?" - I am german speaking - I look up in the dictionnary - do You want(ed) to say: " I do not give the answer - look up Yourself in the schematics or here https://www.ipdb.org/files/820/Williams_1972_Fan_Tas_Tic_Operator_Manual.pdf on page-21 (ori-20): " ... and closes to Ball-Index-Relay" (((so we cannot "Tilt" and get the same ball given))). Greetings Rolf

Thanks Rolf - in this case it wouldn't matter if both sides were energized (except for the additional power drag).

I am gonna let the more experienced of you figure this out to it's entirety and revisit later hoping I will have a much better understanding while actually looking at my grand prix after work.
NicoVolta very interesting that you have come up with all of this.
-Mike

Hi NicoVolta
I take Your (post-1, almost at end) "I don't know why Williams did this" and (post-7) "... cruising on autopilot" --- I come up with a similar question: Here https://www.ipdb.org/search.pl?mfgid=351&yr=1972&sortby=date&searchtype=advanced#1063 the Williams pins of 1972 --- Olympic Hockey, Jan 1972 has the bumpers operated by AC-Current, Spanish Eyes, March 1972 has the bumpers run on DC-Current - THE FUSE IS ON THE MINUS-SIDE of the Rectifier, Honey, May 1972 same as Spanish Eyes --- AND NOW - Super Star, August 1972 has the bumpers run on DC-Current - THE FUSE IS ON THE PLUS-SIDE of the Rectifier, the following pins (example Fan-Tas-Tic) ... much later Space Mission: ... THE FUSE IS ON THE PLUS-SIDE of the Rectifier.

I come up with a similar question - Spanish Eyes and Honey: Shall we move the fuse on the rectifier (from minus-side) to plus-side on the rectifier ? Greetings Rolf

Electrically, shouldn't it be the same either way? The same amount of current would need to flow out as flows in? Unless there's some failure condition I'm not thinking of

This is an answer in search of a problem.

Hi NicoVolta
a similar question - here: http://www.pinwiki.com/wiki/index.php?title=EM_Repair#Game_Specific_Problems_and_Fixes - fixes - shall we do these fixes on every such pin ?

Hi zacaj
I guess that a lot of people do like I do - thinking of DC-Current flowing like water - a reservoir high on the mountain - a tube - under PRESSURE the water comes down - into the village - into the houses - then the water does some work (whatever we want it to do) - then "some kind of exhausted" the water runs out - through a sink-tube, waste-water-tube - finally to the sea So Reservoir on the mointain and the sea are the "Poles of a Water-DC-Circuitry". For Safety Reasons - where do we mount an fuse ? --- we mount the fuse just after the reservoir - before the water (under pressure) comes down to the village.

I know AC-Current is not DC-Current - but when I look at an schematics: I see Transformer - wire to a fuse - then a wire into the pin --- I call this the Power-Side - secured by a fuse. Because of the problem "in the old days the plugs to plug-in into the wall-outlets were only two prongs and so can be plugged-in two ways": For Safety-Reasons I actually would mount two fuses - one on each side of the circuitry --- maybe one is never used - but well - a fuse costs a couple of cents / dollars - so lets mount the two fuses ... Greetings Rolf

I'm not a trained electrician, but I feel like the water leaving the homes is just as much water as what comes out of the reservoirs, and it all comes together into as single river before reaching the 'sea' again. I've never been a fan of the water analogy.

Technically, since it's AC, they're both the power side half the time. A useful way of thinking when reasoning about digital circuits but not actually how it works?

Just between GP and Space Mission alone, Williams made over 20,000 of these games. Just those two alone.

If this was an issue, I would believe that the operators would have alerted Williams. If this was an issue, it would have surfaced long, long before this time. It would have been a discussion at a minimum on RGP, or some other forum.

As I said, an answer in search of a problem.

Williams also produced solid state machines for a decade across multiple systems with a major design flaw in the power supply that could set your transformer on fire, and so many other things. The problem is pretty obvious, as is the answer.

Hi zacaj
Yes just as much water coming down from the reservoir as much then is flowing away through the waste-water-tube(s) - (gallons are gallons) the key-word is pressure --- pressure on the way down.

I didn't want to write so I only said "I know AC-Current is not DC-Current". Here my imagination "AC-Current as water flowing": I have a strictly horizontal tube, diameter one to two inches - I can put the end of the tube into my mouth. I put my thumb on the end of the tube (the end "near me") - I then fill the tube with water - on the other end of the tube is a little compartment - also filled with water. In the middle between me and the little compartment is mounted in the tube an propeller / impeller / turbine. I fill my mouth with water - I take the end of the tube into my mouth and
I PRESS water from my mouth into the tube --- I stop pressing - I then SUCK water from the tube into my mouth - I stop sucking - and again and again --- and I do this pressing / sucking rhythmically - endlessly - I do it 60 times per second --- my pressing / sucking are the HERTZ on the AC-Current - the propeller / impeller / turbine runs - I DO APPLY POWER - I either PRESS or I SUCK --- so the "fuse" should be mounted in the tube NEAR ME. Greetings Rolf

Current is amount of electrons going through the wire. The same amount of water is going through the tube no matter which end you measure at.

Oh, was your switch dirty? Why grind the contacts or sand them with your metal wheel (did anyone mention doing that)? Why not just adjust the switch?

Just curious...

Assuming you discount the little physics note I put up there about preventing score from incrementing immediately, the other purpose may have been to spread the load of the tilt relay. Otherwise the enabling would have happened through a single switch pair.

Question for you - what happens with and without your mod when a score reel coil is detached on one side (and cannot move)?

The answer is you are still vulnerable.

Hi NicoVolta
I agree with You "switch is not needed - maybe it cuts 0.01 to 0.02 seconds earlyer the current flowing to the Score-Drums (a theoretical little 'pro')" --- the switch mounted as is can be part of "causing a blocked situation - a big 'cons' " - Lets say: The Switch on Tilt-Relay that handles Power-Side connection is faulty - faulty stays closed when the Tilt-Relay pulls-in. This fault lets the Points-RELAY stay pulling. The Brake-Part of the Make-and-Brake-Switch on the Tilt-Relay opens --- The Score-Drum cannot pull - its plunger cannot travel and so the plunger cannot open its EOS-Switch - therefore the Points-RELAY stays pulling forever - heats up and gets damaged / destroyed.

Looking-up in the schematics - You were close (A-Go-Go) --- want to look-up "Big Chief": https://www.ipdb.org/machine.cgi?id=240 --- NO SWITCH in the Power-Side-Connection -
Score-Drums and Points-Relays quit pulling because the one-and-only-Switch on Tilt-Relay opens. Greetings Rolf

Age? How old do you want them to get?

For what? A problem that basically isnt a problem?

Nothing is a problem until it is, like this one is.