While you guys are trouble shooting a silverball mania I have one remaining issue on mine. The 4 top 50 point rebounds and the 4 top Bumper switches are not working. All 8 are on the same wiring. Yellow/red and white/brown. I stink at reading schematics so some help tracking down the culprit would be appreciated.

Screenshot_20190930-212734_Drive (resized).jpg

If one switch is stuck closed, non of them will work.

If the 50 point switches is the only switch issue you have then most likely one of those eight 50 point rebound/dead bumper switches is stuck closed. You can confirm if it's the issue by going to switch test mode. Remove the ball from the outhole. See if the game reports switch #34 (50 point switches) is closed.

Feel stupid, a switch was bent closed. I picked it up over the weekend cheap and that was last issue. I was thinking bigger issue.

Thanks guys

This morning I turned the game on and the solenoids work. The relay clicked at boot up, and the game served a ball when I pushed start. So the issues is intermittent, again.

Not sure about the voltages I measured yesterday, but this morning:

T1=5.22
T3=4.02
T6=3.89
T7=3.88

Not sure why T3 & T1 are not equal, unless J3-25 or J3-13 connections are bad? Is there a jumper between J3-25 & J3-13?

Robert

Yes, a likely bad connection on either/both of those pins. There is a brown-white jumper wire between those pins on J3. A common mod for redundancy on these solenoid driver boards is to solder a wire on the back of the board between TP1 and TP3.

SDB_TP3.jpg

I just ran a small jumper wire between the two test points which can be rapidly disconnected if diagnostics have to be done for any reason.

Was left over alligator clips from Comet Matrix strip lighting adapters so free to me to make.

I do the mod inconspicuously

5V_Mod_TP1_to_TP3.jpg

Me too.

The wire gauge is a similar thickness to the other factory jumper links on the board. Holes are 0.8mm drill diameter.
You can use component lead clippings similar gauge to the jumper links already on the board to do the job.

I do the same with the C26 and C23 capacitor ground mods although I use thicker gauge component lead clippings for the C23 mod because of higher C23 surge currents on power-up.

Picture please!!
I never though to do it that way...

I have a random question on a Bally -50 sound board. I've had it on this Paragon for awhile, but have an issue that I'm sure someone has seen before, but I'm not quite sure of.

1 - Big Daddy Cap Kit was already done, work fine for a time after that.
2 - started to get a loud/solid BUZZ sound on boot
3 - took the board off and did the other basic maintenance I never got around to (reflowed header pins, replaced POTs, repinned connector) hoping that would resolve the issue.

Now when I plug the board in, the Potentometer (upper of the two) lit up like a Christmas tree and smoked itself. Also, within around a minute the lower right resistor started to smoke. For the brief period it was on, sound was back, but all were very short (likely due to the potentometer). I've confirmed no pins accidentally made connection.

Any ideas which component(s) to check next?

The C26 negative trace is too thin to drill through so I drill next to it and bend the wire along the trace and solder. Of course you need to scrape the green enamel off the traces to expose bare copper first for the solder to take.

C23_GroundModB.jpg
C26_GroundModB.jpg

Sounds like a problem in the 43V to 12V circuit on the sound board - the sustain pot normally has 12 volts across it and likely it got hit with 43 volts. Check the Q1 TIP29C transistor for a short and the 13V zener diode at CR4.
Power on very quickly and measure the voltage at TP3 (next to the sustain pot) on the sound board. Should be 12 volts.

Quench Great call, sir - both transistor and Zener at C4 are out of spec. Transistor is jacked and Zener has same low resistance both directions.

For replacement - I'm guessing the Zener is a Zener and should be exact, but is there a better alternative for the transistor? (Like How you always replace a TIP122 with a TIP102, etc).

get the C version. TIP29C

I would stick with the original transistor - they should be easy to get. It must be C version as barakandl said. A and B versions are lower voltage spec.
Note the 555 Timer at U7, the pre-amp at U9 (LM741) and the output amp at U10 (LM380) are also powered by the manufactured 12V rail on the sound board - they might now be suspect.
Check diode CR3 (1N4004) while you're there.

When I measured TP3, I only came back with 5.5v, so I knew something was wrong pretty quickly. Well that and I didn't even get through boot up testing before the Potentometer started smoking more and the resistor was uncomfortably hot to touch.

I'll check the full circuit as noted and get to replacing parts. Thanks!

Back in!
Now does anyone know about this plastic?

Missing Plastic (resized).jpg

image-16 (resized).jpg

Hi guys and gals, just joined the club with my first Bally, a Lost World. of course have some questions.

So, everythign works and plays, but the feature lights (inserts etc) are much dimmer than the GI. reading pinwiki and techniek.flipperwinkel.nl and here leads to testing of the rectifier board and testing voltages on TP1 through TP5 as such:

TP1 3.2vdc (low)
TP2 237vdc
TP3 13.6vdc
TP4 6.7vac
TP5 44.5vdc

So the only one that seems totally off is TP1 reading low which not surprising is what feeds the dim feature lights. So before I start ordering stuff is there a recommended kit for repairing? or is it easier/more effiecient to by a replacement from nvram.weebly.com? Anything else I should look at while I'm at it?

because.. pictures.

IMG_20191015_061632 (resized).jpg

IMG_20191015_170203 (resized).jpg

I would test the bridge.
You probably have a bad bridge.
I would also check the power resistor.

That's brilliant! thanks for posting the pics as well. I'm going to convert all my SDBs to this, I was never happy having the extra wires at the back.

I recently read an old Bally Technical Paper (FO-597) for modifying a 2518-17 in order to use it in a game equipped with a sound card. Are those modifications in FO-597 necessary? I thought a -17 board could be used in any newer game (i.e. those using sound cards) so long as the correct EPROMs were installed and jumper mods were done using the well established jumper mod literature (Bally/Stern pinwiki).

R2 should read 25ohms, give or take 10%

The -17 MPU board supports up to 4k bytes of ROM code.
The -35 MPU boards were enhanced to support double the ROM address space up to 8k bytes.
A 2732 EPROM is 4k bytes in capacity.

The electronic sound games were coded under the enhanced ROM address space layout.
You can't jumper a -17 board to run standard game code from a -35 game without performing the FO-597 modification to give it the enhanced ROM addressing support.

Thank you for the clear and concise, thorough explanation!

On Stars, on occasion 500 points and +1 bonus will trigger when the ball kicks into the shooter lane. I think it's one of the two button switches doing this. Aside from banging on the PF in game or switch test is there anything more I should be looking at for these potential phantom switch hits?

Flaky switch cap.?

Great suggestion. I will try to get some spares (we thankfully have a really good electronics place) and just swap them out to see what happens.

What makes the new (replacement) drop targets brick? Is it a change in material from the originals? Was the geometry actually changed with a new mold? I'll have to look, but is there a channel in the back side of the target? Maybe filling it with some epoxy will stiffen it up. I'm guessing, from what I've seen, that if you hit them square and hard they flex and fly back so fast that they don't have time to drop. Any other guesses? I have one game that is very bad with bricks, like 50%+ of shots to the drop targets brick. I'd like to eliminate/heavily reduce this.

Does anybody know who can burn and sell me a sound ROM (U4 on a 2518-51 sound board) for a Bally Viking? Listed as "E802-2, E802-7". Google is failing me.

hobbyroms.com

Meloyelo51 / Matt's Basement Arcade pinside shop got me!

https://pinside.com/pinball/community/pinsiders/barakandl

I've got a game that has the Alltek lamp driver board and is LEDs. Everything works pretty great. The only complaint my serious player friends have is that when you hit the flippers, the GI will blink.

I understand that the GI is on AC, and you're picking up the voltage drop. This has a new power driver board and solenoid board, I think it's by design.

Can anyone suggest any clever ways to prevent that drop (besides going back to incandescents)?

I have had Bally's that do that with incandescents also. Don't think it's a led issue.

Perhaps... though I can’t imagine it’s the design intent. I’d love to find a solution. Some way to buffer it somehow.

Can you post a video? I have a Star Trek and Xenon and I don't recall blinking.

Could it just be poor contact or corrosion on the lamp sockets? There’s lots of YouTube videos about how to fix issues with flakey Bally lamp sockets.

I should say that I’m new to the club with a recently purchased, nicely refurbished Flash Gordon. I have a few lamp sockets that need buttoning up, but otherwise the game looks and plays great. Very happy with it.

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No, it's a recently restored game with brand new lamp sockets. Also, it's the entire GI. I've seen this on other machines with LEDs. I believe folks in this group advised it was just a function of the transformer and the voltage being drawn from the flippers pushes the voltage down just beneath what the LED bulbs are sensitive to... some suggested the only sure-fire way to solve it was converting the GI to DC, but that seems pretty involved.

You might have to put in a separate isolation transformer.
I know, hard core/over the top... but it could work.

Probably just a poor contact somewhere. Did you try cleaning the GI circuit fuse holder? Has the fuse holder been replaced? The old Bally are notorious for weak connections there.

Ah, got it. Thanks for the explanation. I just checked, and my GI dim ever so slightly when I hit the flippers. It is barely noticeable.

Same and Star Trek has a buttload of GI lights compared to Xenon. Slight dimming at best, definitely no flashing. I'd be concerned about connectors which are a known issue on this vintage Ballys. I had to repin all mine at the bridge board and went with Trifurcon for the extra load capacity and all LED for good measure.

That is a common characteristics of the Bally/Stern games of that era.

It’s a new board there as well. I reterminated every connector. I have heard it’s a common characteristic, it’s just being exaggerated by the LEDs.

This question is less of a “it’s broken help fix it” and more of a “how might you try to change it.”

I’ll post a video.

Here's a video, but as you might expect with trying to capture the LEDs blinking, it doesn't really show up.

Live it is much more pronounced. I personally don't care but I'm just tired of people pointing it out to me so I figured I'd solicit some of this crew's wild and wacky ideas.