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oliverthepig

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Hi all,

I'm attempting a repair on a Sega System 16b Altered Beast PCB. I'm open to any suggestions and repair tips. I think that the board has 2 faults which maybe related. There is a screen of repeating garbage. The game sprites can be seen behind this. I think that the Blue is missing. I have the schematics. There is red data and green data making it though J11(74HC273). There seems to be data going into H9 and H10 (74ls245) H9 outputs seem quite low. This data bus attaches to J9,J10 TMM2115BP-10 SRAM. I have attached photos of the symptoms. Looking forward to some hints.
 

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the first thing i always do - if i know there is no physical damage,
pull and read the roms, then check them with mame.

if they are good,
touch every chip - the thermal finger-test works surprisingly well.
if you dont get burned,
i next check the ram.
 
Hi,

Thanks for the reply, will order a usb eprom programmer and check the roms

Cheers
 
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