Tetris blocks keep rotating

Cliff Clavin

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I just picked up a converted tetris and have an issue or two. The seller said they spilled some liquid on the control panel and ever since, the rotate button has not worked properly. As soon as a game starts up, the player 1 blocks keep rotating.

I disconnected the wires from the rotate button and the blocks still continuously rotate. I then disconnected the molex connector that connects the control panel and yes you guessed it, the blocks are still rotating. Also, it appears that the player one start button does not want to work.

I first thought maybe a grounding issue but after disconnecting the control panel wiring completely, the blocks were still rotating.

Does this sound like a tetris pcb issues or a cabinet wiring issue? I haven't had a chance to try a different jamma board as the game is in a friends garage right now. I am hoping to turn it into a joust machine so I would rather the issue be with the board than the cabinet.

One other issue I discovered is the horizontal width adjustment does not seem to work. All other monitor adjustments work great but the horiz width. And as luck would have it, the image is too wide right now. Is this an issue that would be solved by a cap kit?

Thanks all for any comments.

C.
 
It could be a board issue... the way I would check it is, test continuity with a multimeter between the two wires going to the 'rotate' bricks button (is there two of them though?) whichever one you think is stuck on. If they're connected together (they probably will be) you'll find the right one.

Then, unplug the jamma connector from teh board, and check the two wires again. If they're still connected together, there's a short in the wires somewhere... if they're not, then there's a short on the board.
 
On the horizontal thing, do you know what kind of monitor it is? What size is it? Some monitors have different things that make them do that, or it could be the pot is broken or the width coil, or many different things.
 
Lyonsarcade,

Thanks for the advice. I will check continuity. There is one wire going to the rotate and the ground wires.

With respect to the monitor, I believe it's a medium resolution 26" monitor. There was a 15 kHz and a 25 kHz spot on the chassis to connect to. The monitor was currently connected to the 15 kHz. I think I saw a mid 90's date on the monitor somewhere. Sorry not much help here, usually I take pictures of all the tags on the chassis and neckboard so I can figure out report what it is.
 
Well I am very happy to say, problem solved....more or less....Had some time, so I brought a board with me to swap into the Tetris....I took my JROK multiwilliams board and plugged her in and voila, Multi-williams in my tetris cab!

All issues are fixed, the fire button works as it should and other than the size of the screen, everything is working great....My plan is to run joust in the machine using my JROK board as the size of the screen is not really an issue in joust....truth be told, Robotron worked great as well as the screen cut off just part of the outer box....no big deal.....

So the problem lies with the tetris board....so, anyone need a partially working tetris board?
 
Hmmmmm. May have been premature in saying problem fixed. Fire buttons on both player 1and player two not working. Odd. Fugue the ground is good as they use the same ground as the joystick which works fine.

Didn't have time to check much else but will investigate further. Maybe the wrong button wiring is hooked up to this button? I was able to make setting changes on the phoenix pcb so I thought the button was working. When I hooked up an actual button, I couldn't flap on jroks joust. Gotta trace the wiring I guess.
 
Took another look and went through test settings on the pcb. Input test showed player 1 rotate and down was constantly triggered as well as player 2 down. Cabinet plays fine otherwise ( save for a too wide pic) so the input problem is due to pcb issues. Anyone know where to look at on the pcb? Reseated the few chips that I could but problem persists.

Also I read somewhere that you could install a cap to shrink the horizontal width? Anyone have any info on this?

Cheers

Cliff
 
Took another look and went through test settings on the pcb. Input test showed player 1 rotate and down was constantly triggered as well as player 2 down. Cabinet plays fine otherwise ( save for a too wide pic) so the input problem is due to pcb issues. Anyone know where to look at on the pcb? Reseated the few chips that I could but problem persists.

Also I read somewhere that you could install a cap to shrink the horizontal width? Anyone have any info on this?

Cheers

Cliff

I can't find schematics for the board, but you might want to look for hex Schmitt triggers somewhere on the board. There might be a number on the chip of 14584 (Motorola version). This, or a similar chip would control movement, rotation, etc. It would be tough without schematics and a logic probe, but that might be a start.

Good luck!
 
Took another look and went through test settings on the pcb. Input test showed player 1 rotate and down was constantly triggered as well as player 2 down. Cabinet plays fine otherwise ( save for a too wide pic) so the input problem is due to pcb issues. Anyone know where to look at on the pcb? Reseated the few chips that I could but problem persists.

Also I read somewhere that you could install a cap to shrink the horizontal width? Anyone have any info on this?

Cheers

Cliff

Check with Buffett if this thread doesn't help.....


http://forums.arcade-museum.com/showthread.php?t=298727

And from Bob Roberts

http://www.therealbobroberts.net/width.html
 
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