Sony HCD-RV20 - Electrical Adjustments

7
HCD-RV20/RV50/RV60
3. ELECTRICAL ADJUSTMENTS
DECK SECTION 0 dB=0.775 V
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 sup-
ply 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 adjust-
ment.)
6. The adjustments should be performed for both L-CH and R-CH.
7. Switches and controls should be set as follows unless otherwise
specified.
•Test Tape
Record/Playback Head Azimuth Adjustment
DECK A DECK B
Note: Perform this adjustments for both decks
Procedure:
1. Mode: Playback
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. After the adjustments, apply suitable locking compound to the
pats adjusted.
Adjustment Location: Playback Head (Deck A).
Record/Playback/Erase Head (Deck B).
set
main board
IC201
Pin
5 (PB OUT(R))
Pin
wh (PB OUT(L))
main board
IC201
Pin
eh (GND)
+
–
level mete
r
test tape
P-4-A100
(10 kHz, –10 dB)
Screw
position
L-CH
peak
within
1dB
Output
level
L-CH
peak
R-CH
peak
within
1dB
Screw
position
R-CH
peak
MAIN
board
IC201
set
test tape
P-4-A100
(10 kHz, –10 dB)
pin
5
oscilloscop
e
L-CH
R-CH
V
H
waveform of oscilloscope
in phase 45 ° 90 ° 135 ° 180 °
good
wrong
pin eh
pin wh
L
R
Tape Signal Used for
P-4-A100 10 kHz, –10 dB Azimuth Adjustment
WS-48B 3 kHz, 0 dB Tape Speed Adjustment
P-4-L300 315 Hz, 0 dB Level Adjustment
forward
reverse