data east problem ?

[Caveoftreasures]

Any help would be appreciated.
I have a royal rumble.after the machine has been on for about an hour, the dotmatrix goes funny, just completely full of lines...when u turn the machine off, and it cools down, and then turn the machine back on, all goes back to normal..
half of the time, when this happens, machine loses memory and i have to go into menu and reset the freeplay, otherwise it asks for coins to play a game...it doesnt do this all the time, just sometimes.
Games history.
*the machine was losing memory everytime on startup,and a friend replaced the batteries and made them remote, did the solder thing where the battery holder was before he took it off, and made a little repair to the board where a little acid had leaked...but now, i have this prob whereby evertime the machine has been on for an hour,and gets hot,  it starts its tantrum....dotmatrix/memory etc...
shld i replace board or another repair....i do not think its the dotmatrix, i reckon main board ??....
what u think i shld do next ?
regards, brett

[dj10555]

Hi Brett,

When the display fills with lines, can you still play the game but just can't see the display? You may have more than one problem, I would measure the voltage on the back of the DMD. The power supply which drives this often require rebuilding or have dry joints on the back. For the memory problem, I would measure the battery voltage across the ram chip pn the main CPU board to ensure it is recieving the correct voltage. I can repair the boards for these games if you get stuck.

regards Derek

[Strangeways]

Hi Brett,

When the display fills with lines, can you still play the game but just can't see the display? You may have more than one problem, I would measure the voltage on the back of the DMD. The power supply which drives this often require rebuilding or have dry joints on the back. For the memory problem, I would measure the battery voltage across the ram chip pn the main CPU board to ensure it is recieving the correct voltage. I can repair the boards for these games if you get stuck.

regards Derek

I agree - Dry joints and the fuse holders on the power supply board. Check the 5V connector to the DMD board. When the problem re occurs, gently tap the connectors on the DMD board.