Mechanical Adjustment; Electrical Adjustment - Sony WM-FX661 Service Manual

SECTION 4

MECHANICAL ADJUSTMENT

PRECAUTION
1. Clean the following parts with a denatured-alcahol-moistened
sweb :
Playback head
Rubber belt
2. Demagnetize the playback head using a demagnetizer.
3. Do not use a magnetized screwdriver for adjustments.
4. After adjusting, apply screw-locking compound onto the
adjusted parts.
5. Unless specified otherwise, use a specified voltage (1.3V) to
perform the adjustments.
Torqu Measurement
Mode Torqu meter
FWD
FWD CQ-102C
Back Tension
REV
REV CQ-102RC
Back Tension
FF
CQ-201B
REW
Pinch roller
Capstan
Meter reading
20 to 30 g · cm
0.4 to 2.0 g · cm
20 to 30 g · cm
0.4 to 2.0 g · cm
More than 40 g · cm

ELECTRICAL ADJUSTMENT

1. Specified voltage : 1.3V
2. Switch position
DOLBY NR switch
AVLS switch
CASSETTE SECTION
Test Tape
Type Signal
WS-48A 3kHz, 0dB
Tape Speed Adjustmnet
Procedure :
Test tape
WS-48A
(3kHz, 0dB)
1. Playback WS-48A (Tape center part) in the FWD state and
adjust RV601 so that the frequency counter reading becomes
2,970Hz to 3030Hz.
2. Playback WS-48A (Tape center) in the REV state.
Check that frequency counter reading is within 60Hz of the
reading of step1.
Adjustment Point :
[MAIN BOARD] — SIDE A —
— 7 —
SECTION 5
PRECAUTION
: OFF
: OFF
Purpose
Tape Speed Adjustment
Frequency counter
16Ω
+
Set
–
PHONES jack
RV601 : Tape speed