Mechanical Adjustment - Sony WM-FX855 Service Manual

SECTION 4
MECHANICAL ADJUSTMENTS
PRECAUTION
1. Clean the following parts with a denatured-alcohol-moistened
swab:
playback head
rubber belts
2. Demagnetize the playback head with a head demagnetizer.
(Do not bring the head demagnetizer close to the erase head.)
3. Do not use a magnetized screwdriver for the adjustments.
4. After the adjustments, apply suitable locking compound to the
parts adjusted.
5. The adjustments should be performed with the rated power
supply voltage (1.3 V) unless otherwise noted.
Torque Measurement:
Mode Torque meter
FWD
CQ-102C
FWD
back tension
REV
CQ-102RC
REV
back tension
FF
CQ-201B
REW
pinch roller
capstan
Meter reading
18 – 30 g•cm
(0.25 – 0.41 oz•inch)
0.7 – 2.0 g•cm
(0.006 – 0.027 oz•inch)
18 – 30 g•cm
(0.25 – 0.41 oz•inch)
0.7 – 2.0 g•cm
(0.006 – 0.027 oz•inch)
more than 35g•cm
(more than 0.49 oz•inch)
SECTION 5
ELECTRICAL ADJUSTMENTS
1. Specified voltage
2. Switch position
a NR switch
DIR MODE switch : a
TAPE SECTION
Test tape
Type
WS-48A
Tape Speed Adjustment
Procedure:
Test tape
WS-48A
(3 kHz, 0 dB)
set
1. Playback WS-48A (tape center part) in the FWD state and ad-
just RV601 so that the frequency counter reading becomes 3,015
± 10 Hz.
2. Playback WS-48A (tape center) in the REV state.
Check that the frequency counter reading is within 2.5% of the
reading of step 1.
Adjutment Point:
AUDIO BOARD – Side A –
ND501
– 8 –
PRECAUTION
: 1.3 V (DC)
: OFF
Signal Used for
3 kHz, 0 dB Tape Speed Adjustment
frequency counter
32 Ω
+
—
2 REOMTE jack
RV601