Hi goingincirclez +
great - You found and fixed an tricky fault. As (probably others and) MarkG I am (also) not that happy with the theory in post-15 --- specifically the "silent standby of 500-Relay". I put together the stuff from the ipdb-schematics (have mirrowed some part) --- the big question is : WHAT color (wire then blade then blade then wire) had permanent-faulty connection . Also very interesting an answer to the question: A ball rolls to the target - target is moved - blade of which colour ? starts moving - moves and gets in contact with blade / wire color ? --- the both (blades / wires) move and finally get in contact with blade / wire of color ?.
This topic is very interesting - please write about. Greetings Rolf

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Hi goingincirclez
I was working on my JPG (I show here in this post) --- in the meantime You made post-26 - I do not like to do drawings and then not posting --- so I do post.

There is no reason to blame Yourself --- it was a tricky fault. As far as faults can be beautyful: This is extra-ordinary beautiful. In my fake drawing I left-out the stuff "Spinner / Change-Relay". Greetings Rolf

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Hi goingincirclez +
maybe a true story - maybe a fairytale ?

Back in the old days - in 1976 when Williams designed the "Grand Prix". They made a prototype - played it and said: Oh - poor us --- the left and right Stand-up-Switches both advance both (left and right) bonus. We mounted simple two-blades standup-switches - the feature we want does not work with these two-bladed switches.
Hey --- didn't we invent on "Space Mission" an UNIQUE Tilt-rollover-feature*** --- there we had to mount an three-bladed Make-and-Make-Switch --- common-wire-yellow on the first - the first-moved blade. Then on second blade the UNIQUE Tilt-rollover-feature*** (secured / put out of order through an switch opening on Ball-Index-Relay - when Ball-Index-Relay pulls-in) - then third blade to make an bonus.
Hey - lets mount on Grand-Prix also three-bladed Make-and-Make-Switches on the left and on the right. O.K. - they mounted - played the pin and the feature "left and right separately" worked --- but grumble - a grace shot closing only blade-1 and blade-2 (but not both also closing to blade-3) the player gets half of the feature - depending on how we wire blade-2 and blade-3 (blade-1 has / had wire-common-yellow): The player gets on a grace shot either "making 500 points" or then "advancing on the bonus".
We want "all or nothing" we want "BOTH subfeatures or NONE" --- lets move the common wire yellow to third blade and the two feature wires on blade-1 and blade-2 --- and we have the "all or nothing, both or none".
And to veil / obscure / conceal what we did: We draw on both sides in the schematics two two-blades switches - nobody will realize - nobody will ever complain.
And then came goingincirclez and bought new rubbers. End of story / fairytale.

I show the situation in Space Mission --- (rightbound) first blade must have wire-common-yellow. Wire-color-w-b-7 must come second for to eventually activate the UNIQUE Tilt-rollover-feature*** and then third comes the wire-color-blu-w to actuate (in normal play) the Bonus-Advance.

About two months ago I said: My Space Mission plays nice --- I want it perfect / tuned. I always had the idea: When the ball rolls up on the left lane - not completely up - but up enough to actuate the rollover - grumble, I sometimes do not get my bonus advance.
I opened the pin, had a look at - learned about the threebladed switch and the two features --- decided "I do not want the UNIQUE Tilt-rollover-feature*** - I change the setting - I only use it as an twobladed switch for the bonus advance. Shame on me --- reading and writing here in the topic: I did not remember "my Space Mission three-bladed switch" ...

Today I looked up on my Big Deal --- there is NO UNIQUE Tilt-rollover-feature*** implemented - a simple two-bladed switch is mounted - for the Bonus-Feature.

"Aztec" is the same as "Space Mission" - ALSO an threebladed switch for UNIQUE Tilt-rollover-feature*** plus "regular bonus advance".

UNIQUE Tilt-rollover-feature*** --- on Grand Prix http://www.ipdb.org/machine.cgi?id=1072 ipdb has some text on this UNIQUE Tilt-rollover-feature*** - we can click onto and we land here http://www.ipdb.org/glossary.php#Tilt_Rollover some text and a link to http://www.ipdb.org/search.pl?ft=tilt.rollover&sortby=date&searchtype=advanced - two SS pins and the Grand Prix and the Liberty Bell and the Hot Tip.
In the ipdb-list missing are Space Mission and Aztec --- maybe because the UNIQUE Tilt-rollover-feature*** is hidden / covered by the "Add bonus feature" ?
Greetings Rolf

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