Strange problems with Missile Command

[MaximRecoil]

First, here is a video of what's going on on the screen - link.

I got the machine a few weeks ago and it worked fine when I first turned it on, for about 2 minutes and then the screen started rolling and the graphics became garbled. It hasn't worked correctly since.

Another thing that is happening is; when I turn the machine on, the coin meters usually start repeatedly incrementing (sometimes they don't but it sounds like they are trying to). Also, pressing the player 2 start button causes one of the coin counters to increment one time per button press. This makes no sense to me as I wouldn't expect the player 2 start button to even share a circuit with the coin meters. Also, the player 1 & 2 start buttons usually flash when the machine is on, though sometimes they are just steadily lit.

The board has the "Missile Command Multigame and High Score Save Kit" from Braze Technologies in place of the original ROMs. I've already reseated all of the socketed chips on the board, including those on the Braze kit and the Braze kit itself, and cleaned the card edge and card edge connector.

Other things I've done include:

• Removed all 8 of the original 4116 DRAM chips, added sockets and replacement 4116 chips from Bob Roberts.

• Replaced the "Big Blue" capacitor on the power supply with a new one from Bob Roberts.

• Rebuilt the A/R II-02 board with a capacitor/transistor/resistor kit from Bob Roberts.

None of those things solved the problems.

[RayB]

All those things you did were very wise to PREVENT damage and failures, but your board has already been damaged. That's why it's not fixing it.

Put the machine in test mode. That will help you out a whole lot more.

[MaximRecoil]

All those things you did were very wise to PREVENT damage and failures, but your board has already been damaged. That's why it's not fixing it.

Put the machine in test mode. That will help you out a whole lot more.

I've done that. I get the same rolling garbage screen, plus some static out of the speakers, sometimes of varying pitches, but mostly just a low staticky hum. The coin counter stops incrementing in test mode.

[Level42]

What is your 5V on the game PCB ?

[MaximRecoil]

What is your 5V on the game PCB ?

+5.03 VDC using the "+5V" and "GND" test points on the board.

[SirPeale]

Can you adjust the garbage out using the monitor controls?

edit: never mind, I just watched your video.  Yep, your board is broken.  Sounds very similar to what was going on with my Centipede.  With the coin counters and the screen garbage.  I had bad ROMs and broken solder joints.  I don't think that's the problem here.

[MaximRecoil]

Can you adjust the garbage out using the monitor controls?

edit: never mind, I just watched your video.  Yep, your board is broken.  Sounds very similar to what was going on with my Centipede.  With the coin counters and the screen garbage.  I had bad ROMs and broken solder joints.  I don't think that's the problem here.

Do you think it could be a problem with the Braze kit? The Braze kit replaces all of the original ROMs. I wish I had an original ROM set to try in there, but the board came with the Braze kit and no original ROMs.

[SirPeale]

I can't say.  Possible?  Of course.  The only way to be sure would be to get it checked out on another MC.

[RayB]

I've done that. I get the same rolling garbage screen, plus some static out of the speakers, sometimes of varying pitches, but mostly just a low staticky hum. The coin counter stops incrementing in test mode.

OK so compare the beeps and static to what the manual says about test mode beeps and static noise.