The "barf" is on the lamp board, which controls feature lighting. Let's work on that board later, as it may or may not be bad. Your immediate problem is that the MPU isn't booting all the way. That's why you have no sound or displays.

Let's start to troubleshoot with your MPU board, the one with the red LED on it. When you turn on the game, watch that LED. It should flicker very fast then off, then flash 7 more times. Tell us, how many flashes do you get when you power the machine on?

Also, you have connected a remote power backup (three AA batteries) to the MPU board but do you have a blocking diode in the line? That would be in the red wire between the battery pack and the MPU board.

do those 7 flashes coincide with the beeps on boot?

This sounds exactly like my Meteor booting problem (except my original boards were recently bulletproofed/extensively rebuilt and tested in my tech friend's machine for a weekend--I've got a button battery instead of the AA)...I think I'll try to get over to it tomorrow. I need to install the new sound cables and check the power supply with a multi-meter.

They do

Make sure you have blocking diode or the mpu will try to charge them.... not good.

OK, then Refer to the Pinwiki, section:

https://www.pinwiki.com/wiki/index.php?title=Bally/Stern#Bally_.2F_Stern_MPU_Board_LED_Never_Lights_or_is_Locked_On

Please report back your findings following those recommendations.

There are no beeps on the boot that I have ever experienced.

You seem to have a stuck-on LED on the MPU, which indicates it's not booting at all. Diagnosing & repairing such problems generally requires expertise & experience! No-boot can be caused by MANY things, but if the game was working before, it's more hopeful that it's not simply a dead reset circuit on the MPU (repair requires electronics experience), and something to do with a bad connector/socket.

You could start by isolating the MPU from other boards/connectors (with everything powered off!), and seeing if it will boot: Disconnect everything going to the MPU except J4 (lower-left connector), including the ribbon-cable at the top which goes to the sound-board. If you still get a stuck-on, you possibly don't have proper power to the MPU, or maybe one of the socketed chips has corrosion or is loose. You can then try flicking each socketed-chip sharply with a fingernail, and try again (not a science, but sometimes will temporarily give you a good enough connection to boot). Failing that, you're probably into bad DC power to the MPU, via the Solenoid/Driver Board (upper-right) which does the 5v and 12v regulation, and the power supply/rectifier in the cabinet. You can try wiggling connectors on both boards to see if there's a bad/burnt connection.

Honestly, you may also have any number of other problems, including blown fuses, or even improperly inserted connectors when the game was put back together, so the above is only some stuff you can try without getting out a multi-meter and schematic.

Good luck! Meteor is still_ one of my favourite games, and will be great fun when you get it working!

Really? I thought this 7 beep thing was a thing with the mpus from bally/stern.

Yes you are correct. My Meteor beeps with the flash.

Stern mpu200 games do the beep thing coinciding with the LED's. Earlier mpu100 games do not, and Bally games don't do it at all.

I removed it from a couple test builds of flight 2000 (along with the startup test being moved to the self-test instead of bootup) with instant bootup and I *hated* it. I'm used to it on Williams and Gottlieb games (not system 1) but bally/stern.... I want that delay.

Can you take pictures of the sound board?

I would get a rebuild kit for the capacitors at minimum. I personally would get new cables, it’s a cheap ish and those things are like 40yrs old.

You’ll also want to see if the header pins have corrosion and need to be cleaned or replaced.

Great!

My neighbor has a wild fyre with the sound cutting in and out, so I may be doing some work on a sb100 too!