looking for a space invaders part 2 pcb schematic / help

cricketman98

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I recently came to acquire a space invaders part 2 cocktail table and the machine powers up but there are 2 rows of test patterns and machine makes no sound any advice would be awesome. This is the oldest machine ive worked on. Thank you can post pictures of any thing if needed
 
Not sure what "2 rows of test patterns" means, patterns on SI are usually in columns. Lots more information would be of use.

Taito, Midway or something else?

Picture of fault and pcb's would probably help a lot.

If you want to start checking things, check the +5V, +12V and -5V power rails. Measure them on the game board.

This game uses 3 voltage rails on certain IC's so be careful if you start probing around the IC's, especially the RAM, uP and possibly ROM's. Shorting a pin accidently while probing can cause more problems than you already have.
 
Not sure what "2 rows of test patterns" means, patterns on SI are usually in columns. Lots more information would be of use.

Taito, Midway or something else?

Picture of fault and pcb's would probably help a lot.

If you want to start checking things, check the +5V, +12V and -5V power rails. Measure them on the game board.

This game uses 3 voltage rails on certain IC's so be careful if you start probing around the IC's, especially the RAM, uP and possibly ROM's. Shorting a pin accidently while probing can cause more problems than you already have.
I am sorry for the lack of information it is a taito table. thank you though. here are pictures of the board and screen i do apologize if i use incorect terms for things.
 

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It looks like your boards are the Taito Space Invaders Part II 3-layer board stack.

From your screen picture it looks like at least some of the video timing and color generation is working. That is the test pattern you are referring to.

Space Invaders Color, used the video timing signals to output different colors based on the screen region. This was combined with the game video for that position to create what looked like a color game.

Monitor also appears to be working (showing picture). Picture is not full screen and has part missing, most likely related to the fault(s) on the game boards.

The color on the monitor indicates at least part of the timing is working and your 5V might be ok. No video and no sound indicates the game is not actually running.

Start with power supply voltages. If they are all there (+5V, +12V and =5V) and you do not have the component level repair skills this is probably a board set to send out for repair.
 
I know there is a self test on the tvn intruders space invaders board set which I believe is activated by dip switch 4. the game is a black and white version of space invaders and has a 3 board set. the schematics on the robotron page for the intruders is the one that I use and had some schmeatics for color on it that were not used and probably was not supported on my rom set. the sound board also looks different on this setup then my intruders setup. I wrecked one of my rom sockets and just found it was easier to put in the braze kit and have more options then to replace the socket with the original rom
 
That board has color outputs, but no color video ram - in essence it would use the row counter to change the colors, emulating color strip overlays from the BW days.. So you are probably seeing a solid white screen, but the circuitry that keys colors to rows is kicking in, looking more complex than it really is.

That board is a PITA to work on. The monitor in those cocktails have an unbelievable number of electrolytic caps in it too, making it a question of 'juice worth the squeeze'. Unless of course you really just like a challenge!
 
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