Star Tech Journal

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Nintendo R-Type Audio ProbleID
Scott E. Serpa
Arcade Services, Inc.
Albany, Oregon
PROBLEM
Recently we had an R-Type experience an audio
problem. No audio at lower volume and full
volume would produce only distortion.
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SYMPTOMS
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A quick check with a signal tracer showed good
audio coming out of the game PCB, leaving the
amplifier in the monitor as suspect.
The voltage on the collectors of transistors Q302
and Q304 and the base of Q303 and Q304 were
over double their specific voltage.
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All the transistors tested good but this high
voltage reading indicated they were not con-
ducting.
SOLUTION
The culprit turned out to be resistor R305 a 2 70K
resistor located in between the heat sinks of
Q303 and Q304.
This resistor was open but not discolored in any
way.
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