The lamp just lets the player know the skill shot is active. Are you certain that light works? Go into test mode to check... swap out the bulb.

Second question, go to switch test and confirm the skill shot switch is working. If not, clean/adjust/diagnose why it is not registering.

Post here the results.

Only other possibly thing... start a game and look at the score. Do you have points even before you launch the ball? If yes, you have a switch scoring points before you launch the ball. THAT ACTION will remove the skill shot because the game thinks the ball is already in play.

A little superglue or epoxy into that crack *might* fix it well enough if it's just cracked and not broken off and the spring merely slipped thru the crack.

Good work!

As far as the arrow for the maze, does the light ever turn off, say in attract mode or lamp test? Just wondering if the lamp is locked on or if there's a switch that may not be working, leading to the game not allowing you to enter the maze. Have you verified all the switches in the game are working properly now that you've squared away the other issues?

No prob!

So just to clarify further, are these the 2 arrows you're having trouble with? Any other lamps locked on similarly?

1377379568.png

Could you post pics of each of the problem lamps under the playfield? It appears the 2 "maze qualified" arrows share an SCR on the lamp driver board--sounds like the SCR is bad causing them both to lock on, or one of those 2 lamp sockets is touching metal/ground nearby. See the "Left and right saucer maze arrow" on the diagram below for it's place in the schematic (on the lamp driver board diagram).
Screenshot_20210211_165106_com.google.android.apps.docs(1).jpg
The lamp on the lower right is likely working. It looks like it's there to indicate when the value labeled on the plastic above it is lit. (5,000+2 moves) Screenshot_20210211_174633_org.mozilla.fennec_fdroid(1).jpg

The light for the ghost on the left might actually be wired into the general illumination, in which case it won't blink at any point unless all the GI lights blink (some games control the GI lights with a relay to flash them all off/on or temporarily turn off the GI for added effect). A pic of that lamp under the playfield should help us determine if that's the case here.

You're welcome!

We all gotta start somewhere, no need to apologise if you're unfamiliar with this any of the concepts or terminology--there's lots to learn! I'm happy to try to explain any of this stuff further--just ask if you have any questions.

Anyway, thanks for the pics--i agree it looks like the sockets aren't shorted or anything like that.

To answer your other questions: A5J3-20 translates to:
A5 (Lamp Driver Board) here's where that info is in the schematic: 1584786968.png

J3 (connector J3)
-20 is referring to the pin number on that connector.

Also note the other number on the left "78". That's a color code that can be looked up on the wire color chart elsewhere in the schematic. Here's the chart: Screenshot_20210211_201904_com.google.android.apps.docs(1).jpg

The first digit is the main wire color, the second digit is the stripe/tracer color. So in this case you have "78"--orange (7) with a black (8) stripe/tracer... So you'll find an Orange/black wire at pin 20 of the J3 connector on the Lamp Driver Board (A5). That wire runs from A5J3-20 down to the playfield, finally ending up at the ground tab for both of those sockets for the "maze qualified" arrows. Note there's 2 orange/black wires at one of those sockets and one orange/black wire at the other one? Those 2 lamp sockets are "daisy-chained"--the orange/black wire runs from the lamp driver (A5J3-20) to one lamp, then an *additional* orange/black wire is run from that socket to the other socket. From your pics: Screenshot_20210211_202505_org.mozilla.fennec_fdroid(1).jpg

That orange/black wire is on the ground side of the lamp socket. The DC voltage for the lamp is provided by the wire on the other part of the socket. What the SCR does is essentially provide a path to ground for the voltage coming into the lamp. When the SCR activates, the lamp comes on. When an SCR goes bad they often will "lock on" causing them to turn the lamp on and keep it activated for as long as the game is turned on. Looking at the schematic for the lamp driver, it appears that Q41 is the SCR that drives those 2 lamps. I'm thinking that's probably our culprit here. 1613214454(1).png

Do you have a multimeter?

Pretty much any multimeter should be able to handle the tests we'll need it for. I would think something in the $20-30 range will probably be more than sufficient. We'll need it to be able to test ac and dc voltage, resistance, continuity, and diode test. Almost all meters are capable of doing all that and more. Something like this would work: https://www.homedepot.com/p/Klein-Tools-Manual-Ranging-Digital-Multimeter-MM300/206517192

Keep us updated. With a voltmeter you should be able to get these lamps sorted out. Testing Q41 may be the next step but honestly, that transistor is .40 cents and I would just order 10 of them if you are waiting on a meter too.

I have a box full to the top with bad Transistors and disc caps. On average these Bally machines from this era have at least two disc caps or transistors per machine that failed when I encounter a machine that hasn’t been worked on in years.

Nah, you need a diode test to test transistors and resistance.
I believe the transistor you need is 2n5060. Been drinking so hopefully that’s correct!

Right side. You can see the diode symbol next to the little battery symbol on your meter. What your readings are supposed to be I’m not sure. Someone here can give you more details about that

FB8307DA-F255-414E-A373-D80014746F3E (resized).jpeg

Here's what Clay's guide says about testing the SCR. I believe this is one of the larger MCR-106 SCRs the lamp board. Black lead will always be plugged in center port on meter, red lead will always be in the right slot except hi amperage testing (you'll likely never need to put the red lead in that port). Meter testing unfortunately isn't always accurate for testing SCRs, but I've caught bad ones with a meter. Set the meter to diode test and check the SCR with the following instructions. You can check them on the front side or back side of the board. What i like to do is compare readings with other adjacent SCRs to see if anything stands out. Given the symptoms, i won't be surprised if it is indeed a bad/locked on SCR causing the issue. Anyways, here's the procedure:

MCR106-1 Lamp Driver SCR test:

Put the black lead of your meter on the outside "cathode" leg (labeled
"C") of the SCR.
Put the red lead of your meter on the outside "gate" leg (labeled "G")
of the SCR. Your meter should read .4 to .6 volts.
Swap the meter leads. Now the meter should read 1.4 to 1.6 volts.
If your meter reads anything outside the values above, replace that
MCR106-1.

Yes, both the SCRs and the smaller transistors on these older Bally lamp boards frequently need replaced on newly acquired games, so buy a quantity of them. I usually don't have much problems with them after the initial overhaul. I think those older lamps when they get dark start sucking more current and then the aged transistors go kaputz.

Pretty easy to measure, and compare these against a known working channel. Another method is to set your meter to read DC volts, attach your meter ground to circuit ground, turn the game on lamp test, and compare points around the transistor and SCR between good working and non-working channels. On a old Bally with many lamp problems that's my MO, replace all the bulbs first, then tackle lamp board transistors.

Any updates? Waiting on parts? That's my least favorite part of this hobby

Right on. Readings are saying it's good or maybe slightly out of spec, but I'd go ahead and replace it anyway. It's good to get familiar with this type of testing even if it doesn't always give you 100% accuracy. In the future you can use the same procedure for testing transistors, chips, and diodes. It may not always reveal the culprit but it's a quick easy way to get started troubleshooting certain problems.

Make sure to orient the new scr correctly on the board!

Fingers crossed, it should hopefully solve the issue.

Great stuff, man! Congrats on the fix!!!

Good job! Now frunch and I can take a coffee break while you help everyone else fix their games. Lol.

As far as i can see, that is a suitable replacement. Also looks like you have the correct SCR's on the chart. An easy way to verify would be to check the wire color on the ground tab of each of those 5 lamps and compare them with the chart. If they match up, you have the right ones.

I don't know if there's any unused SCRs on your lamp board, but some games don't utilize all of them allowing you to "steal" one to replace the bad one with. Have to check the schematics and see if any aren't being used. That game has a bunch of lamps though, so you may not find any to spare.

I'd still order the ones you have listed though, just thought I'd point out that there's sometimes a chance you can do that too

Before doing any of that though, be sure the socket itself isn't shorted internally. Take the lamp out and get a good look inside the socket. Make sure nothing got bent internally or stuck in the socket, and that the wiring too the socket is not touching anything adjacent. I'd try measuring between the 2 solder tabs of the socket (with the bulb removed) and make sure you're not getting a beep with the meter in continuity test. That could indicate an internal short in the socket (i would think, i don't have my games in front of me). Either way, it should be a fairly easy fix

One other thing--try an incandescent bulb instead of an LED (i think you have LEDs installed) just to rule out the LEDs as a possibility. Not likely, but could be worth looking into if nothing else pans out.

It appears you are using LEDs for those feature lamps. LED bulbs will not work correctly in the “feature lamps” of a classic Bally/Stern game unless you upgrade your lamp board or add on the Seigecraft adapters to the lamp board. Switch back to incandescent or upgrade to the above.

The Seigecraft solution is cheaper and would allow you to keep your repaired lamp board.

https://www.siegecraft.us/presta/index.php?id_product=44&controller=product&id_lang=1

If not, some will always randomly be dimly lit, flicker, or not turn on/off properly.

Glad you are getting the game sorted out, it’s a lot of fun if you understand the rules and is such an underrated classic Bally title.