Sony HCD-DX60AV, Service Manual

Page: 18 / 76

18
HCD-DX60AV/RG70AV
SECTION 4
ELECTRICAL ADJUSTMENTS
2. Turn the adjustment screw and check output peaks. If the peaks
do not match for L-CH and R-CH, turn the adjustment screw
so that outputs match within 1dB of peak.
3. Mode: Playback
4. Repeat step 1 to 3 in playback (REV) mode.
5. After the adjustments, apply suitable locking compound to the
parts adjusted.
Adjustment Location: Playback Head (Deck A).
Record/Playback/Erase Head (Deck B).
Screw
position
L-CH
peak
within
1dB
Output
level
L-CH
peak
R-CH
peak
within
1dB
Screw
position
R-CH
peak
set
test tape
P-4-A100
(10 kHz, –10 dB)
L-CH
R-CH
waveform of oscilloscope
in phase 45
°
90
°
135
°
180
°
good wrong
PANEL board
PHONES jack (JACK701)
oscilloscope
V
H
+ +
–
–
32
Ω
32
Ω
0 dB=0.775 V
DECK SECTION
1. Demagnetize the record/playback head with a head
demagnetizer.
2. Do not use a magnetized screwdriver for the adjustments.
3. After the adjustments, apply suitable locking compound to the
parts adjust.
4. The adjustments should be performed with the rated power
supply voltage unless otherwise noted.
5. The adjustments should be performed in the order given in this
service manual. (As a general rule, playback circuit adjustment
should be completed before performing recording circuit
adjustment.)
6. The adjustments should be performed for both L-CH and R-
CH.
• Test Tape
Record/Playback Head Azimuth Adjustment
Note: Perform this adjustments for both decks
Procedure:
1. Mode: Playback
DECK A DECK B
set
test tape
P-4-A100
(10 kHz, –10 dB)
level meter
PANEL board
PHONES jack (JACK701)
32
Ω
+
–
Tape Signal Used for
P-4-A100 10 kHz, –10 dB Azimuth Adjustment
WS-48B 3 kHz, 0 dB Tape Speed Adjustment
forward
reverse