NAD 2100 - Main Amplifier Adjustment; Important Notes for Adjustment; Center Voltage Check; Idle Current Adjustment

MAIN
AMPLIFIER
ADJUSTMENT
IMPORTANT NOTES:
A.
1)
Before
adjusting,
remove
input
signal
and
load,
and
set
Speaker
impedance
switch
to
8
ohms
(reset
to
4
ohms
when
finished).
2)
These
adjustments
are
always
necessary
after
repair
to
main
amplifier.
3)
After
repair,
it
is
recommended
to
use
current
limiter
(70-100W
lightbulb)
in
mains
line,
for
initial
turn-on.
CENTER VOLTAGE CHECK
1.
Connect
DMM
between
Ground
and
R-471
(L
channel)(R-472,
R
channel)(amplifier
output).
2.
Turn
on,
and
read
voltage.
Specification
OV
+
100mVDC.
IDLE CURRENT ADJUSTMENT
1.
Connect
DMM
across
P-402(+)
and
P-403(-),
and
adjust
R-437
for
reading
of
15mV
+
2.5mVDC.
2.
Repeat,
using
P-404(+)
and
P-405(-),
adjust
R-438.
FINAL ADJUSTMENT
1.
Leave
power
on
minimum
5
minutes.
2.
Repeat
center
voltage
check
and
idle
current
adjustments.