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(Topic ID: 196282)

Very Strange Meteor Drop Target

By oldschoolbob

3 years ago

Topic Stats

  • 29 posts
  • 9 Pinsiders participating
  • Latest reply 3 years ago by Coyote
  • Topic is favorited by 2 Pinsiders


Linked Games

  • Meteor Stern Electronics, 1979

Topic Gallery

There have been 8 images uploaded to this topic. (View topic image gallery).

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#1 3 years ago

The Meteor game has a drop target that spells M-E-T-E-O-R. Each letter has an insert light. As the target drops the light goes out – when all targets are down they all reset. Everything works fine unless the last target is the “R”. Then the insert light don’t go off and the unit won’t reset. If the “R” goes down in any other sequence (first, second, third, etc.) it works fine but not if it’s last.

I’ve had the unit out three times to clean and adjust the switches. I’m sure that isn’t the problem.

Any suggestions?



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#2 3 years ago

Sounds to me the R drop target switch is not registering when the drop target drops. But why it only does it when hit last is weird.

Are you using an Altek board? Do you have any other games with the same MPU?

#3 3 years ago

I'd check the diode on the "R" (diode-test on your multimeter).

#4 3 years ago

My first thought was the switch not registering. I took it out 3 times to check the switches - I even checked them with a multimeter to be sure they were closing while on the bench. It worked fine on the bench. I even checked all the diodes and they're good. It's a regular MPU-200.

I also thought the problem could be with the multi-pin connector on the unit but then it wouldn't work in any sequence.

I don't have another game here but I know someone with another Meteor - but he's a few miles from me. Do you think the MPU could be the problem?



#5 3 years ago

When you hot the r switch in that sequence, does it score but not turn off the light and reset? Or no score at all? Maybe a loose ground wire going to the switch? I cant remember how it looks, but are the grounds daisy chained like the ballys of that era? Pics?

#6 3 years ago

Also -
Are you running an Alltek board, or standard MPU?

#7 3 years ago

I'd have to assume a switch matrix issue...

#8 3 years ago

Just a thought, maybe worth looking into.

I had a meteor when it came out. After a year or so, I started having all kinds or weird switch issues.

I finally started on each leaf blade switch in the game. On many, the fiberboard spacers between the leaf blades, appeared "wet".

I'd lower them from playfield, clean with lacquer thinner, dry, and with a jeweler file, file the spacers on the solder/lug side between the blades to thoroughly clean.

I think the flux was mucking up the works. After a thorough cleaning, I had no further issues.

LTG : )

#9 3 years ago

amkoepfer, when the "R" is the last target the light stays on and it don't score. Even going over the roll-over to get the next target down don't score - the solenoid will click, the target will drop but the light stays on and it don't score or reset. Yes the grounds are daisy chained and I checked all the connections. - see photo.

Coyote, it's a standard MPU 200.

zacaj, if it was a matrix issue wouldn't I have problems with other switches on that row or column? Every thing else works fine.

LTG, I have completely disassembled and cleaned that unit except for the leaf switches. If I can't find any other problems I may just try that.



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#10 3 years ago

Have you tried a switch test? I'm curious is there is another switch closed throwing it off. On mine, it as easy to notice because it would score points before you even did anything.

#11 3 years ago

Just so you know I'm not crazy I made a video showing what it's doing.

#12 3 years ago

Thanks AMBoggs, I never thought to try the switch test. I'll try it tomorrow.


#13 3 years ago

When in switch test only the lowest switch number will show.

M = 32
E = 31
T = 30
E = 29
O = 28
R = 27

If I drop each target (and raise it back up ) the proper number will show.

If I drop the targets in sequence (M-E-T-E-O-R) (and leave them down) the display will show 32-31-30=29-28 but the 27 will not show.

If I drop the targets in sequence (R-O-E-T-E-M) the 27 will show until I drop the number 31 “E”, then the number 28 will show. If I raise up the 31 “E” the number goes back to 27. It’s like the 31 is canceling the 27.

Please help.


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#14 3 years ago

Are there any closed switches when you enter the test? Assuming you have the ball out of the game.

I'm going with a diode on the switch matrix.

This site has a pretty good explanation and trouble shooting.

#15 3 years ago

As well as checking diodes, if I recall, there is a common strand connecting all of the switches. Check that to make sure it's well-soldered and unbroken between switches.
Also, check to make sure the switch panel - the metal bracket where all the switches are mounted to - is securely fashioned to the back of the drop target assembly. (Possible that screws are loose, and the 'E' pushes the stack away far enough where the 'R' switch suddenly closes.)

#16 3 years ago

Coyote, the common wire is the white/yellow and I have checked it several times. I've also checked the attachments and everything is secure. Mechanically it's sound.

AMBoggs, the switch test shows 0 when I start.

The diodes tested OK but they are original. With nothing else to check, I think I'll replace all 6 diodes.

I'll let you know how it turns out.

Thanks for all your help.


#17 3 years ago

Cool, just had to bring up the silly, since I've seen worse.

If replacing the diodes doesn't do it, swap the two PIAs on the MPU. (U10 with U11.) Since everything else was ruled out, you could just have a bad PIA chip..

#18 3 years ago

Pia was what i was thinking, if it registers in other sequences, just not that, pia is a good spot to start

#19 3 years ago

I changed all 6 diodes and still have the same problem.

I don't have any extra new PIA's - and GPE is out of stock. I have some old ones but I'm not sure they're good (un-tested) I guess I could change them out and see if anything changes.

Would just swapping U10 and U11 make a difference?

By the way, U10 and U11 are NOT a matched set. Did I read somewhere that they must match?



#20 3 years ago

If you swap then and the problem changes you know you've got some pia issue. Not sure about the matching thing...

#21 3 years ago

Im not sure if they are matched or not, i may have some pias laying around, ill take a look tomorrow and if i do ill send it to you

#22 3 years ago

The 5101 Rams chips U8 & U13 must be matched otherwise you will get weird audio issues.

See this post

If U8 & U13 are socketed it may be worth a try and swap them over.

#23 3 years ago

U8 and U13 are a matched set from GPE. ( I knew something had to be a matched set).

I have a few old PIA's - I'll try changing them and see what happens.

I'm not good at changing IC's in the game so I'll pull the board out and change them on the bench. It'll take a while. I'll let you know what I fine.

Thanks everyone - you've all been very helpful.


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#24 3 years ago

Curious to see if anything happens when you switch them, yeah.

#25 3 years ago

Just to let everyone know - I pulled out the MPU and replaced the PIA's with two that I had laying around. I didn't think that was the problem so when put the board in I didn't re-connect the J5 (sound card).

Guess what - IT WORKS. When I drop the targets in any sequence it resets when they're all down.

Now I'll go back and connect to sound.

Thank you all for your help - I think we got it.


#26 3 years ago

PIA issues can generate pretty random behavioural issues, and swapping them with known-good ICs (from another board, or new-stock) is always worth a try. They are always socketed, and it is unlikely you'll burn the good ones out in the swap. Good catch!

#27 3 years ago

I want to thank you all again. I would have never thought to replace the PIA's.

I reconnected the sound card and played a few games (even set high score). The game works great.

Thanks everyone.


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#28 3 years ago


#29 3 years ago

Awesome! Glad you got it!
And your playfield looks really nice. I'm jealous.

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