Mechanical Adjustments; Electrical Adjustments; Tape Deck Section - Sony XR-1800R Service Manual

SECTION 3

MECHANICAL ADJUSTMENTS

1. Clean the following parts with a denatured-alcohol-moistened
swab:
playback head pinch roller
rubber belt capstan
idler
2. Demagnetize the playback head with a head demagnetizer.
3. Do not use a magnetized screwdriver for the adjustments.
4. The adjustments should be performed with the power supply
voltage (14.4 V) unless otherwise noted.
• Torque Measurement
Mode Torque Meter
Forward CQ-102C
Forward
CQ-102C
Back Tension
Reverse CQ-102RC
Reverse
CQ-102RC
Back Tension
FF, REW CQ-201B
• Tape Tension Measurement
Mode Tension Meter
Forward CQ-403A
Reverse CQ-403R

TAPE DECK SECTION

1. The adjustments should be performed in the order given in
2. The adjustments should be performed for both L-CH and
Test Tape
P-4-A063
WS-48A
Meter Reading
25 – 55 g•cm
PB Head Azimuth Adjustment
(0.35 – 0.76 oz•inch)
Procedure:
1.5 – 4 g•cm
1. Put the set into the FWD PB mode.
(0.02 – 0.06 oz•inch)
25 – 55 g•cm
(0.35 – 0.76 oz•inch)
1.5 – 4 g•cm
(0.02 – 0.06 oz•inch)
50 – 150 g•cm
(0.69 – 2.08 oz•inch)
2. Turn the screw and check the output peak value. Adjust the
Meter Reading
more than 60 g
(more than 2.12 oz)
3. Check the phase in the FWD PB mode.
– 12 –
SECTION 4

ELECTRICAL ADJUSTMENTS

this service manual.
R-CH.
Type Signal
6.3 kHz, –10 dB
3 kHz, 0 dB
test tape
P-4-A063
(6.3 kHz, –10 dB)
4 Ω
set
speaker out terminal
screw so that the peak value in channels L and R coincides
within 2 dB.
within
L-CH
2 dB
peak
output
level
R-CH
peak
screw
position
L-CH
peak
test tape
P-4-A063
(6.3 kHz, –10 dB)
4 Ω
L-CH
set
4 Ω
R-CH
speaker out terminal
Screen pattern
45 °
90 ° 135 ° 180 °
in phase
good
0 dB= 0.775 V
Used for
head azimuth adjustment
tape speed adjustment
level
meter
+
–
within
2 dB
angle
R-CH
peak
oscilloscope
V H
+ +
– –
wrong