Super Cobra Repair Logs

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Repairer: Paul Swan

BOARD NO: 0067
GAME: Super Cobra
MANUFACTURER: Karateco
DATE: 1981
HARNESS: KONAMI-S

SYMPTOM (19/05/96)



Absolutely dead. No video. No sound.


SOLUTION



Using a logic probe to check on CPU activity indicated that the video Z80 wasn't running. The reset line was inactive but the clock wasn't running. The clock crystal was running OK as were the two drive buffers in IC7A (LS368). The two stage divider chain in IC7B (LS107) was running OK. The divided clock was then fed into pin 12 of IC7A (LS368) to be inverted but the logic probe indicated no output at pin 11. Changing IC7A fixed the game completely.