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Output power amplifier board
Adjustments
Ouiescent current
Test condition:
Approx. 10 min. warming up time from cold con-
dition without signal applied.
Connect a VT\M across R203/R204 for left/
right channels respectively, i.e. between the top
terminals of R203 and R205/R204 and R206,
see figure.
Adjust Rl17/R118 (t) for 40 mV reading on the
VTVM.
Peak clipping
Connect an oscilloscope to left/right speaker
output across 8 ohms load.
Apply a I kHz signal and drive the amplifier to
just below clipping point.
Adjust R127/R128 (r ) r" that the Peak Clipping
indicators on the front lights up. Then fine adjust
the potentiometers down until the lights just goes
off.
rd> FRONT
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l-l r-l l-l l-l Measuring p oint, quie s cent current.
