Mechanical Adjustments; Electrical Adjustments - Sony TC-WE625 Service Manual

SECTION 3

MECHANICAL ADJUSTMENTS

PRECAUTION
1. Clean the following parts with a denatured alcohol-moistened
swab :
record/playback/erase head
rubber belts
idlers
2. Demagnetize the record/playback head with a head
demagnetizer.
3. Do not use a magnetized screwdriver for the adjustment.
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.
Torque Measurement
Mode Torque meter
Forward CQ-102C
Forward
back CQ-102C
tension
Reverse CQ-102RC
Reverse
back CQ-102RC
tension
FF/REW CQ-201B
pinch roller
capstan
Meter reading
30 to 65 g • cm
(0.42 to 0.90 oz • inch)
DECK A : 1 to 6 g • cm
(0.014 to 0.083 oz • inch)
DECK B : 2 to 9 g • cm
(0.028 to 0.125 oz • inch)
30 to 65 g • cm
(0.42 to 0.90 oz • inch)
1 to 6 g • cm
(0.014 to 0.083 oz • inch)
70 to 120 g • cm
(0.97 to 1.67 oz • inch)
– 8 –
SECTION 4

ELECTRICAL ADJUSTMENTS

PRECAUTION
1. The adjustment should be performed in the publication.
(Be sure to male playback adjustment at first.)
2. The adjustments and measurement should be performed for both
L-CH and R-CH.
• Switch position
DOLBY NR switch
DIRECTION MODE switch : A
• Standard record position :
Deliver the standard input signal level to input jack and set
the REC LEVEL control to obtain the standard output signal
level as follows.
– Record Mode–
AF OSC
10 k Ω
attenuator
600 Ω
LINE IN
Standard Input Level
Input terminal
source impedance
input signal level
Standard Output Level
Output terminal
load impedance
output signal level
Test Tape
Tape Contents
P-4-A100 10 kHz, –10 dB
WS-48B 3 kHz, 0 dB
P-4-L300 315 Hz, 0 dB
0 dB = 0.775 V
Test Mode
1. Turn ON power switch pressing "REC MUTING" switch of deck
A and B at the same time.
At first, all the fluorescent indicator light up, then the system
returns to normal display. (However, "0. 00" is not displayed on
the counter.)
2. To release the test mode, turn OFF the power switch.
: OFF
level meter
47 k Ω
+
set
–
LINE OUT
LINE IN
10 kΩ
0.5 V (–3.8 dB)
LINE OUT
47 kΩ
0.5 V (–3.8 dB)
Use
Azimuth Adjustment
Tape Speed Adjustment
PB Level Adjustment