BGW 8000 - MODULATION - Leds

MODULATION - LED's <Signal Indicators)
The amplifier
output is c('lnnected to J402 through R406 to Q404 and Q40.5. Q404 is
cOMected
as a common emitter stage and Q40.5 is connected as a common base
stage. When the output signal exceeds approximately +0.6 volts (positive output).
Q404
conducts. When the output signal exceeds -0.6 volts (negative output) Q40.5
conducts. When Q404 or Q40.5 conduct the collector current flowing through R408
forward biases and turns on Q406 thus lighting
the yellow modulation LED 0402.
OVERLOAD - LEDts
The red overload LED
040 I works in the same manner as modulation LED's except
that the input signal from J402 is attenuated by R40.5 and R403. This means that
the input signal is approximately 36 volts will cause Q401 and Q402 to conduct.