Well - I managed to fix the MPU that was in it - but I could always throw that into the Spy Hunter that was 12v nuked thanks to a careless TP tie in by the previous owner (Mentioned above) and stick one of the 2 I have coming from you in there ...Or the Paragon that was recently resurrected with your MPU... (hence why I ordered 2 MPUs... always like to have a complete set of your main boards on hand with all the Bally/Stern work I do!)

so - I'm finding plenty more wrong with this stupid Spy Hunter as I go along. Quick question on Bridges/power rectification/checking my understanding;

The TP3 in the cab could read far too high if it isn't under load. However, if it is under load (and looking at my schematics - that 12 Unreg is being fed to both the SDB to make into 5v as well as the Cheap Squeak to do its own power rectification) - so say, the cheap squeak was unplugged but SDB was still plugged in and make a nice, smooth 5v... and the power rectifier is still measuring 18v - that's gotta be the problem right there.

Blue 14VAC is good, so it's safe to assume that CRs 5-8 should be replaced to repair the circuit, correct?

18vdc is normal if the driver board is plugged in. The filter cap holds the voltage up all the way. You should get about 12vdc when the driver board is unplugged and 15-18vdc when plugged in. Pretty normal for the -54 rectifier board games to be a little on the high side for all voltage supplies. My black pyramid and the kings of steel I used to have both was like 7vac on the GI.

That's exactly what I thought, but then C10 on the cheap squeak shot at me like a party popper and I was trying to figure out why.

Oddly enough, going back and trying it now (even with C10 visibly toasted) - it... works? I know they're just smoothing caps, but still surprised to see it functioning with multiple torched parts. (C22 is also gone from before I just noticed). I'm going to replace that and the other caps to be safe.

Who knows what voltage was going to it before I bought it... Again - I've repaired my share of boards, but there's a reason I took a look at this hack job and decided repin/confirm wires and drop 3 of your boards in it to start with was the way to go. - Thank you again by the way

I'm restoring a '78 Bally Strikes & Spares. The playfield glass molding has some chunks missing. Any idea what the part number is and where to get this?

IMG_1055 (resized).JPG

I don't see why this wouldn't work. It's pretty standard on Bally games.

https://www.pinballlife.com/playfield-glass-side-rail-plastic-channel.html

I've got a -35 MPU problem. Cleaned off corrosion and replaced 2 sockets. At first the board went through all 7 flashes, paused, then did it again. Continuously rebooted. I replaced U7, U8 and U11 chips with known good ones form another board. Now the LED is locked on. Removed all the chips except U6, U9, and U11 (following instructions in pinwiki). LED is still locked on. I posted another thread if anyone can help. Thanks.

https://pinside.com/pinball/forum/topic/bally-35-led-locked-on#post-7377576

A while back I could have sworn I saw someone post a chrome or brushed steel transformer cage. Does anyone recall or have a link for that? I believe the person may have been selling them, but for the life of me I can't find them.

cage (resized).jpeg

I only saw this very necro post:
https://pinside.com/pinball/forum/topic/early-bally-ss-transformer-cages

Don't think anyone has offered replacements for sale.

Thanks. I was coming up with these same results. I must have seen something that was part of someone's rebuild Bally that looked great, but perhaps they were not selling them.

Some of the grounds inside my coin door are falling apart. What’s the recommended wire guage to replace?

499F8FF9-4A34-4E80-89EA-5E3451E85007 (resized).jpeg

https://www.marcospecialties.com/pinball-parts/600-5006-18

I wonder if you could make that yourself with ring terminals soldered/crimped to a normal ground strap and then put shrink tubing around it if you need a shorter length?

Sure it will work, The braided wire will hold up better with metal fatigue around the door hinge. It must be reliable.

Later Bally's had green insulated wire with crimped eyelets.

Much better than those earlier junk pieces of metal tin that rust.

agreed i swap all of them to green ground copper wire on my games-

18 ga or something beefier? I may do the same.

yeah some good 18 gaude stranded green wire from the usual electronic place do the trick.

After reading this thread I checked each of my pins (Lost World, Speakeasy,Flash Gordon and Medusa) to see what condition the ground straps were in. The Lost World and Flash Gordon had the yellow insulated straps in good shape. The Speakeasy had the original stranded wire type in good shape. Much to my surprise the original stranded wire on the Medusa had very neatly been cut off!

Any guesses why someone would have done this? The pin has worked perfectly since I bought it 4 or 5 years ago.

IMG_2776 (resized).jpg

IMG_2779 (resized).jpg

If everything is right it will have no impact on operation. Generally speaking its protection for the humans in case of a short to ground.

In your example let's put forth the hypothetical case of the power switch failing internally and routing the hot side of the switch to ground through the switch body and thus the metal plate its mounted in.

If the plate is grounded, circuit protection kicks in. If ungrounded and you touch it, odds are the hot will pass through you on it's way to ground.

Thanks! I will replace ASAP. Still can't figure why someone cut it off but I guess that's not really that important.

Well it's not important until YOU are the ground path.

Someone might have changed out the switch or coin door and could not have been bothered to hook everything up proper.

Going to order from Tayda Electronics, any recommendations what to get all while I'm ordering, what is good to have on hand in general?
Got already 1N4004, 1N4007, 1N4148 and 0.047uF 50V Ceramic Disc Capacitor in the cart
I'm sure there is a boatload of stuff that I should get for a full rebuild of a old Bally SS (Paragon) while I'm ordering.
I got all new boards from AllTek and I think I got all plug housings
But what about Fuses (the manual says they are 3AG on the rectifier board: so is 6.3x32mm always 3AG and I can get those, or, does 3AG denote something else than physical dimensions - I do understand the difference between fast and slo blow), and all other stuff that I'm not thinking off of?

You should get .100 and .156 connector pins to rebuild the connectors in the head. If you don't do it now you will have to do it soon enough.

Alright just got a Bally Space Invaders into the shop today and all the GI lighting is out. I am going to check the simple stuff first like fuses and burnt connectors. Any other suggestions that might cause all the lighting to go out?

I think I’d look in the direction of the GI connectors at the transformer next.

Check and then repin all of the connectors. First step on these.

I've been having trouble with my Centaur. The MPU and driver boards are original. The rectifier is a Weebly board. The game will not boot. The GI will turn on but nothing else happens. There is a green LED on the MPU that lights up very faintly. I checked the voltages:

MPU:
TP1: 4.2v
TP2: 11.26v
TP3: 22v

Rectifer:
TP1: 7.96v (6.5)?
TP2: 248v (230)
TP3: 11.57v (12)
TP4: 7.22AC (7.3)
TP5: 45.6v (43)

The Weebly says 6.5 for TP1 directly on the board instead of 5v. Yet, it still seems high. Every once in a while the game will boot, then TP1 on the MPU is 5.1v. Any thoughts on what I should test next or if I have a bad voltage regulator?

Thanks in advance for the help!

Is there any corrosion on the MPU? Original connectors? How about a high res picture of the MPU? Try reseating the connectors to the original boards, but if they are original, I'd suspect a poor connection (it there is no issue with the boards themselves).

Bad connection @j4. 4.2v is too low for the board to boot.

There is no corrosion that I can see. Looks like the original connectors. I'll check J4 as the other person posted about.

IMG_8175.jpg

I checked J4 at pins 16 and 17 and I'm getting 4.35v from each.

4.28v on TP1 on the solenoid driver board.

What voltages does you have at the test points on the solenoid driver boards at TP1, TP3, and TP5?
TP1 and TP3 should be just above 5volt, and TP5 around 12volt.

Also, you do have battery damage on your board and it is starting to creep around the ground plane. It is dangerously close to the nvram, and may have already reached the socket. Be careful before it eats away the socket/traces and legs on the nvram.
2023-02-22_16-13-53 (resized).png

Selling a few Bally items from parts bin.

Make a reasonable offer plus shipping via usps. I’ll include four plastic nail glides in each package, I have way too many of these things as well!

Bally transformer cage with related screws =SOLD
Bally Playboy grotto overlay
Bally backglass metal lift channel and plastic trim pieces (from a Fathom?)
Bally Medusa playfield window
Bally Paragon shooter lane cover =SOLD

Not Bally stuff, but too lazy at the moment to make posts over there.
Williams Bally lockdown latch pieces

The following are free, just cover shipping:
Gottlieb Genie (system 1) power supply board bracket
Gottlieb paperwork
21A3C41D-285A-4866-AB10-E7D8CEE1F76E (resized).jpeg3C45F127-EC95-446F-A3AB-DC857D1D4E47 (resized).jpeg5A88CB2D-0C19-4F52-A6BC-B1E7DA59F4E7 (resized).jpeg741320F4-5C57-428C-A1B4-0CFE31EF9D32 (resized).jpeg393C8567-3857-4C06-B1B5-90F796B0BD0D (resized).jpegB13B2BAA-3B81-42A6-91E4-A7763C5CCFCB (resized).jpegC0269E75-9352-4E3C-8A8E-411A0EDCDE56 (resized).jpeg884F7D79-DA90-41E3-BB06-FE3BFC7226AE (resized).jpegBC73D8CB-1085-4FE2-9FC2-277E77693CF3 (resized).jpeg2A0AA43A-F0DA-4C78-A8CC-B4B339D40B86 (resized).jpegFE48D741-5A7C-410F-84A9-A42D8E4D7F29 (resized).jpeg62FDA5D2-E419-4AA6-96FD-CA6E297AA532 (resized).jpeg
6568DF09-E67B-48AB-9FE3-5E27CA4A17B6 (resized).jpegAD24F920-1232-40EF-BA29-72B20101A675 (resized).jpeg

Medusa playfield window sold

Grotto overlay sold

TrueJedi

I have a Space Invaders that is emitting a little hum from the transformer when powered on. It's like a "standard transformer hum" and hardly noticeable with the coindoor closed and playfield down and glass on. When I start a game though, the hum increases in loudness, definitely louder and annoying. And when the game plays any kind of sound effect, the hum disappears (or goes back to the original quiet hum) until the sound effect is done, then it gets loud again. Is this a "recap the sound board" problem or something else entirely? I have not reseated any connectors or played around with anything else as of yet.

Are you absolutely sure_ the hum is coming from the transformer, and not the speaker(s)?

original transformer?

https://pinside.com/pinball/forum/topic/transformer-interchangeability

Hum is from speaker after all. Had to move out the game so I could open it up, so I wasn't hearing it just thru the coindoor opening. Game is quiet when I power on, then I start up a game and get the hum. I turn the speaker down at the pot and hum is gone. I would guess/hope this is a recap the sound board fix; although I see in another post that this did nothing and it was a ground issue. I unscrewed the board and let it hang free, and the hum was the same when I started a game, so I don't think that's it.

While I'm on the subject, I have a second -51 sound board, also from a Space Invaders. The sound doesn't get above "barely audible", even turned all the way up. The pot works, as when I turn it all the way down, it's silent. Just barely audible when turned up. Any ideas what would be the prob here?

Also on same subject: here's an ebay listing for cap kit for the boards in question. C8 on both above boards is 470uf / 16v and that's also what the manual specifies. This cap kit comes with a 1000uf / 25v for the C8 location. I know the voltage isn't a problem but is the 1000uf going to present a problem? Was this maybe an upgrade from a Bally service bulletin or something? Or just plain wrong?

ebay.com link: itm

Okay, I was just making sure - if the transformer WAS the one actually humming, a cap job on the sound board wouldn't fix it.

Yeah, caps would fix this. Also possible a diode or resistor is out of spec, though it's been a loong time since I've looked at that board, so I couldn't help on which ones.

couple questions.
I have a Bally Lost World I'm working on. Main manual does not have mech parts. Was looking for spring p/n's for the slings, kick out etc

Now that GPE and BDE are closed, any cap kits or is it a diy? I see marco has a couple, but figure I would try to rebuild/look at the rectifier board too.

Planetary pinball has the parts manuals on line.

thank you!
https://www.planetarypinball.com/williamsbally-parts-manuals

I've bought cap kits and other parts fron Yorktown Arcade before. They sell on eBay, but might also sell here as well.

Sad, I was not aware of that. GPE was my go to when I was heavily into pin rebuilds.

I buy parts and caps from Peter all the time, good quality stuff. If you can't find what you need just email and he can usually put a kit together for you. https://www.arcadepartsandrepair.com/

Long Shot, but if anyone has a head from this era of pins I need one for a Black Jack cabinet I just picked up here in CO. Thx!

617569CE-E49F-4717-8CDA-46540E1B6C8D (resized).jpeg

Just recapped the board and unfortunately that didn't fix it. Still getting the speaker hum, only during a game, and only when no sound effects are being played. Don't know what to try next.

One other thing to note that's unrelated, I'll occasionally get a humming/buzzing sound when one of the flippers is activated. It's not every time, maybe once every 20-40 flips during a game, and it stops when I release the flipper button. It's coming from the flipper coil/solenoid itself, I just raised the playfield and flipped a couple dozen times to make certain. Ideas?

Check the coil stop is tight to the coil itself and not loose. May need to loosen screws, push stop toward coil and retighten. I had this happen and that was the fix.