Marantz SD4000 - LED Peak Level Meter Adjustment; Recording Bias Current Adjustment

6.5
LED
PEAK
LEVEL
METER
ADJUSTMENT
SET UP
1.
Power
voltage:-
50
or
60
Hz
AC
voltage
rated
for
the
unit
to
be
used
in
a
market
country.
.
TAPE
SELECTOR
switch
position:-
NORMAL.
.
Input
terminal
:-
J601,
J621.
. Test tape used:- MTT-150
. Tape Speed:- 1-7/8 ips (4.75 cm/sec).
PROCEDURES
. Supply DC 3 V between J601 and J621.
. Depress the PLAY button.
. Adjust R602 and R622 for OVU LED meter read-
ing.
. Remove DC 3 V from J601 and J621.
. Play the test tape MTT-150 back.
.
Adjust
R610
and
R630
for
+2
dB
LED
meter
read-
ing.
POWER
SUPPLY
14
6.6 RECORDING BIAS CURRENT ADJUSTMENT
SET UP
1. Power voltage:- 50 or 60 Hz AC voltage rated for
the unit to be used in a market country.
2. TAPE SELECTOR switch:- METAL.
3. Load:- Measuring instrument input impedance.
PROCEDURES
Set up the tape deck in the recording mode of opera-
; tion. Connect the VTVM to R906 (Lch) and R907
| (Reh). Adjust the variable resistor R912 and R913 _
for 2mV VTVM read.
NOTE: Proceed both for the right and left channels
in the same manner.