Marantz 4100 - Channel Separation

9.
10.
1.
a AWN .
Measure
the
total
harmonic
distortion
with
the
analyzer
and
verify
it
is
less
than
0.3%.
NOTE:
Any
parasitic
oscillation
in
the
amplifier
will
be
displayed
on
the
oscilloscope,
when
capacitance
is.switched
into
the load.
Switch the distortion analyzer back to SET LEVEL MANUAL.
(Do not adjust sensitivity of analyzer.)
Change
the
frequency
of
the
audio
oscillator
and
distortion
analyzer
to
1KHz.
Adjust
audio
oscillator
output
as
necessary
to
have
a
full
scale
reading
on
the
O-1
scale
on
the
analyzer.
Measure the distortion, verifying it is no greater than 0.3%.
Repeat steps 7 and 8, changing frequency to 20Hz.
Distortion should be no more than 0.3%.
Check for parasitic oscillations; there should be none.
F. Channel Separation
Set
audio
oscillator
to
20KHz.
Connect
oscillator
to
front
left
channel
AUX
input
only,
with
shorting
plug
(10K
ohm)
in
all
other
channels
AUX
input.
Connect
distortion
analyzer
to
front
left
channel
speaker
output
terminals.
Adjust
oscillator
output
until
distortion
analyzer
indicates
0
dB
(2.8V).
Measure
RF,
LR,
RR
channel
output.
Distortion
analyzer
should
indicate
-30
dB
or
less.
Repeat
step
1
and
2
with
substituted
channel
driving.
If
indication
is
not
less
than
-30
dB,
adjust
input
wires
to
preamp
board
until
reading
is
-30
dB
or
less.
105 TO 125VAC
50/60 Hz
SLO -BLO
VARIAG
AC OUTLETS
WATTMETER
AC WATTMETER
O TO 150 WATTS
AC VOLTMETER
0 TO 150VAC
Figure 1. AC Power Control Box Simplified Schematic