Nad 90 Service Manual
I
I
LU
w
0
w
BIAS
2.
The
proper
adjustment
amplifier
ADJUSTMENT
bias
adjustment
is
necessary
exhibits
overheating
PROCEDURE
is
most
if
any
of
of
the
the
important
transistors
output
to
are
transistors
assure
replaced
correct
under
performance
in
the
normal
power
operating
of
amplifier
condisions.
the
amplifier.
circuitry
or
Bias
the
INDICATOR
-----:--.—..-—-—------.
DC
Voltmeter
REMARK:
3.
ADJUSTMENT
Bias
the
can
point
also
at
AND
ADJUSTMENT
VR6O1a,
be
adjusted
which
CHECK
R624b
the
--
b(1Kohm)
using
by
line
wattmeter
POINTS
a
.-t----------
line
shows
R624a
Adjust
R624a,
wattmeter.
very
slight
for
0.006
b
(0.33
Adjust
increase.
REMARKS
---
—
0.015
with
ohm)
the
VR6O1a
V
across
-
NO
SIGNAL
and
VR6O1b
-
to
H
v
B
V
b
601
60
7.
0027
PRE-AMP
BOARD
(TOP
VIEW)
100
—.
‘00
609).
q,,)
E)
•—
®
Q
t0o
ogo
(D
o
0;
®();;
co)
0
<_
II9)——
I0o_>
n
.9)’
;
4
‘•-
zSo
(IOO
—I
‘—_—
zco_
Go
-
0.
:q
ED
q
-
:
‘z
CL
P06)
SO6)
qLO
z
C-’
4
Loading...