Apr 172016
 

Game showed a static white screen at boot.

Checked the clock and it was fine, then I checked if the 68000 was reset correctly and found out that it didn’t get any reset signal.

Tracing back I came to a capacitor which had a leg unsoldered.

ThunderHoop

 

After fixing it, the game booted correctly

TH

 

I started a game but I soon noticed that it the pcb played sometimes random or wrong music/sfx.

The game has no FM chip, so the OKIM6265 is responsible for music and sfx and there is only one soundrom.

Checking the circuit in detail I noticed one jumper for selecting 8Mbit rom was broken in half.

After resoldering a new one, the music and sfx was restored correctly.

Thunderhoop2