Mechanical Adjustments; Electrical Adjustments; Tape Deck Section - Sony CFD-CD777SMK2 Service Manual

SECTION 4

MECHANICAL ADJUSTMENTS

PRECAUTION
1. Clean the following parts with a denatured-alcohol-moistened
swab:
record/playback head
pinch roller
rubber belts
idlers
2. Demagnetize the record/playback head with a head demagne-
tizer. (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 unless otherwise noted.
6. Power supply voltage: 12V dc.
Torque Measurement
Mode Torque Meter
Playback CQ-102C
Back tension CQ-102C
Rewind
CQ-201B
Fast foward
Tape Tension Measurement
Tension Meter
CQ-403A
playback head
erase head
capstan
DECK-A DECK-B
Meter Reading
30 – 60 g•cm
(0.42 – 0.83 oz•inch)
1.8 – 7 g•cm
(0.025 – 0.097 oz•inch)
55 – 120 g•cm
(0.77 – 1.66 oz•inch)
DECK-A DECK-B
Meter Reading
more than 60 g (2.12 oz)
SECTION 5

ELECTRICAL ADJUSTMENTS

TAPE DECK SECTION

1. The adjustments should be perfomed in the order given in the
service manual. (As a general rule. Playback circuit adjust-
ment should be completed before performing recording cir-
cuit adjustment)
2. The adjustments should be performed for both L-ch and R-ch
unless otherwise indicated.
• Switch and control position
FUNCTION switch .......................... TAPE CD/RADIO OFF
MEGA BASS control ..............................................minimum
VOLUME control ................................................... maximum
BALANCE control .................................... mechanical center
Standard Output Level
SP Out
Load impedance 4 Ω
Output level 0.775 V (0 dB)
Test Tape
Type Signal
WS-48B 3 kHz, 0 dB
P-4-A063 6.3 kHz, –10 dB
Record/Playback Head Azimuth Adjustment
Procedure:
1. Mode: FWD/REV playback (DECK A)
FWD playback (DECK B)
test tape
P-4-A063
(6.3 kHz, –10 dB)
set
2. Turn the adjustment screw for the maximum output levels. If
these levels do not match, turn the adjustment screw until both
of output levels match together within 1 dB.
L-CH
peak
output
level
R-CH
peak
Screw
position
CFD-CD777SMK2
0 dB=0.775 V
Phones
32 Ω
0.25 V (–10 dB)
Used for
Tape speed adjustment
Head azimuth adjustment
DECK-A
DECK-B
level meter
32 Ω
+
–
PHONES jack (J301)
within
1 dB
within
1 dB
Screw
L-CH R-CH
angle
peak peak
11