the manuals have issues.

when the games were changed after the manuals were printed, they almost never issued manual corrections or reprinted the manuals.

You can often tell a change happened because the font on the schematic is different. If the schematic changed after production began, they did normally issue another schematic with a note saying at what serial number the change happened.

another sanity check is look at the manual for the next game of the machine type and see if that game manual has the change. In this case, the next game is sun valley and the switch is listed as R2.

when there's a discrepancy between the manual and schematic, believe the schematic.

it was added in showtime and is probably in all the magic square games after that. Earlier games broadway and night club had a slightly different circuit and didn't need the switch.

the sun valley manual describes the switch as "safety circuit (anti-cheat relay)". Not very clear. Beach time says it's "circuit to energize anti-cheat relay"...that's where it's at, but not what it does.

functionally, when the extra ball trip relays trip it prevents power from getting back into the feature circuits when cycling the game for extra balls.

if you have played for extra balls, it also prevents the anti-cheat relay from powering after the game has been turned off/on unless the trip bank resets.

just as a note, it appears the way the manuals were done was take an existing manual drawing and make changes to it for the new game. They did a much better job getting it right in the early manuals. Some of the later ones from the mid-1970's are a mess.

Agreed. Wholeheartedly!

they added the switch because there's a bug in key west and big show.

the problem is wire 85-4. CU 5C and 5D will pulse closed when playing for extra balls, and that will effectively connect wire 10-7 on the magic square feature unit to wire 30. Depending on what step the magic square feature unit is on, you could:
- step the magic square feature unit.
- trip the spot 2/18 trip relays if the score discs and mixer 3 complete that circuit

on night club and broadway, wire 85-4 only goes to the score disc. While 5C closing also completes a circuit thru the score unit when the scores are at the 4 level, for the scores to jump you also need 7A to close. Since 5C and 7A don't close at the same time, there's no problem.

you've got it figured out. An open-at-zero switch on the timer unit is functionally equivalent to the a wiper finger that connects on every timer unit step except reset, so it's ok.

one way to sanity check is to look at the manual/schem for the next game in the series. In this case, sun valley. That manual/schem still shows the outer ring wiper finger and bazillion rivets like show-time.

cypress gardens uses the open-at-zero switch and the outer ring wiper is used for something else.

so, you have some possibilities:
- bally made the change in the factory
- someone replaced the timer unit with one from a later game (solder on lugs look factory?)
- someone just updated the existing timer unit with the later circuit by adding the switch and moving the 38-3 wire from the lug to the switch (most likely)
- your head guts are from a different machine (not likely)

wiper fingers on the outer ring of rivets are the ones most likely to have contact pressure issues. The open at zero switch is more reliable.

if you had a problem with this circuit, you wouldn't get balls lifting after the first one.

the usual problem with the yellow button is misadjustment of the switches behind it. There should be three. Make sure the middle one (powers the start relay) closes as late as possible when pushing the button. The other two switches you want to close as early as possible.

You should be able to push the yellow button in partway and have the extra ball trip relays trip and the red button relay open without the start relay powering to cycle the machine.

ideally the red button switches can also be adjusted so a partial button push powers the red button relay but not the start relay. Half-pushing the red/yellow buttons will then turn the extra ball light off/on.

jumpering timer unit lugs 7/8 (wires 57-7 and 83-6) and 9/10 may or may not be noticeable. The timer unit is in the circuit to prevent early tripping of the before 4th and before 5th trip relays. Without the timer unit wipers in the circuit, you're gambling that the trough switches won't be closed (due to the balls shifting in the trough) when other switches in the circuit are also closed - i.e. the lifter start relay switch or ball lift cam 2B switch.

if the c-shaped arm hanging below the ball lifter is nicely centered/straight in the lifter, the trough balls shouldn't move much side-to-side as the lifter goes up/down, and you probably don't need the timer unit in the circuit - if the trough switches are well adjusted...which can be tricky since the blades don't move a lot.

no reason not to remove the jumpers assuming the rest of the circuit is factory. If those trip relays tripped early, you'd disable moving the numbers but enable payout and extra balls early.

why the manual lift button switch is gone...well...if the ball lifter switch is working right, it's not needed.

it may have been removed to get around a possible race condition. If someone pushed the manual lift button while the balls were rolling right in the trough, the lifter could raise a ball when it shouldn't. You'd need to push the lift button when:
- the rightmost ball is far enough into the lifter to be lifted rather than pushed left back into the trough
- the balls haven't rolled right far enough to open the trough switches

also, if someone held in the manual lift button and shot the ball immediately when it was ejected into the runway, the lift motor would not stop (lifter start relay switch would be almost always closed) and it's possible balls wouldn't raise because they can't roll into the lifter fast enough. Kinda useless from a player point of view, but it would add wear on the parts. Simple solution is get rid of the manual lift button.

EB trip relay switch R3 isn't needed anymore. The added open-at-zero switch on the timer unit connecting 91-1 and 38-3 removes the need for both the timer unit wipers and R3.

the below schem shows factory and your game. It will work the way it is, or you can replace the missing wipers and switch blades if you have the parts and put it back to factory.

for whatever reason, someone decided that to raise the first ball, you still need trough switch 8 to close. To raise the rest, all that matters is a ball is sitting on the ball lifter switch under the pin at the bottom of the lift chute.

circuits above the top of the schematic piece below determine if a ball should be lifted...depends on trough switch closures and the extra ball unit wiper position. For the first five balls, the EB unit wipers don't matter.

blmod (resized).png

jumpering 7/8 and 9/10 are removing the timer unit wipers from the circuits that trip the before 4th and before 5th trip relays.

why someone made that change there's a few possibilities:

- they changed the timer step up circuit so the timer unit starts self-stepping sooner...effectively time limits the game, but you'd have to get rid of some of the timer unit functions like they did (is the before 5th selector lock trip relay switch R3 shorted closed?)

- they had issues with timer unit stepping and just hacked around the problem

- side effect of other changes to the game

to know for almost sure, you have to figure out what all the wiring changes are doing to see if any one change makes sense. Sometimes the modifier did a good job figuring everything out, sometimes they screwed up.

you have a different schematic? I could really use the one that doesn't have the switch at 9C with wire 57-7.

notice on the schem that the font for that switch is different...that's a hint they added that switch after the original schem was drawn. There's a similar fonts at:
- REFLEX UNIT and MAGIC SQUARES FEATURE UNIT DISC around F28
- AFTER 5th at G34
- OPEN AT ZERO SELECTION FEATURE UNIT and ANTI_CHEAT RE. at I7
- TRIP RE. at E4
- a few switches around L1

if the differences are minor between your two schems, some hi-res pictures/scans of the schematic of the changed areas are good enough and I'll modify the one I have. If you aren't sure or there's a lot of changes, can I borrow the schematic to scan?

if you do scan the schem, please overlap the scan chunks around 25%. That'll allow software to automatically stitch the pieces back together into one image.

pictures of the entire schematic would be great. I can see at least three differences in the images above from the schem I have.

the ball lift cam 2 switches close sometime when a ball is being lifted. Typically they close when the lift arm is almost back down to the bottom, but you'd need to look at the cam to see where the lobe is.

the switches close very briefly.

in your case, when you shoot the 4th ball, the 5th ball is raised and that's when the before 4th trip relay should trip.

if your timer unit is still jumpered out of the circuit, the before 4th relay should trip any time there's no ball on the trough switch 4 rollover and 2B closes. You can shoot all five balls, raise the playfield and manually lift the ball lift cam 2 stack and see if the before 4th trip relay trips.

if manually lifting the stack works, then it's likely just the 2B switch needs cleaning/adjusting so the cam lobe reliably closes the switch.

if lifting the stack doesn't work, the only thing left is trough switch 4, the plug connections, the switch on the before 4th trip relay, or the trip relay coil.

p.s. in case I wasn't clear above, pics/scans of the entire schematic would be great (with each image overlapping some..e,g, one image is A1-A9, the next is A7-A15, etc). The images above look like around half of it. So far, only the piece with 2-9 on it has wiring differences that I see. thx!

btw, if you're figuring out how the circuits work, there's two things to keep in mind:

1] timing.

there's rarely timing diagrams. Bally only provided them on a few late model machines. I made a few and posted them on bingo.cdyn.com - see http://bingo.cdyn.com/paper/paperlist.html. The timing would likely be the same for similar machines.

in this case, you have two things happening - ball lift cam 2A is stepping the timer unit, ball lift cam 2B is tripping a trip relay. Since those switches are on the same cam/switch stack, they operate at the same time...which seems like it wouldn't work reliably due to a race condition, except....

2] when step units move their wipers

when the plunger is pulled into a step unit coil STEP-UP coil, the wipers don't move. The wipers move when the coil power is removed and the plunger is pulled out of the coil by the springs on the ratchet pawl arm.

when a step unit reset coil is powered, the wipers immediately spin back to the reset position.

-------

so in this circuit, when ball lift cam switch stack 2 goes up the cam lobe, the timer unit step-up coil is powered (but wipers don't move) and the before 4th trip relay trips. When switch stack 2 goes down the cam lobe, 2A opens and the timer unit wipers move.

except for beach beauty, you have to go all the way back to surf club to find a machine that didn't have a ball lift cam switch in the before 4th/selector lock trip relay circuit. It's possible no production show-time's left the factory without ball lift 2B in the circuit so they never needed to put an "effective at serial" notation on the later schematic.

Damn, I gotta get my Showtime in my shop & get that thing working!
Yours looks great