Sony HCD-RX80 Service Manual page 31

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.
within
L-CH
1dB
peak
output
level
R-CH
peak
Screw
position
L-CH
peak
3. Mode: Playback (FWD)
test tape
P-4-A100
(10 kHz, –10 dB)
pin 1
L-CH
main
L
board
CN207
R
set
R-CH
pin 3
waveform of oscilloscope
in phase 45 °
good
4. Repeat steps 1 to 3 in playback (REV) mode.
5. After the adjustments, apply suitable locking compound to the
pats adjusted.
Adjustment Location: Record/Playback Head (Deck A and B)
and main board.
reverse
forward
within
1dB
Screw
position
R-CH
peak
oscilloscope
pin 2
V H
90 ° 135 ° 180 °
wrong
Tape Speed Adjustment DECK A
Note: Start the Tape Speed adjustment as below after setting to the
test mode.
In the test mode, the tape speed is high during pressing the
HIGH SPEED DUBBING button.
Procedure:
1. Turn the power switch on.
2. Press the SPECTRUM ANALYZER button,
ENTER/NEXT button and EFFECT ON/OFF button simul-
taneously.
To exit from the test mode, press the POWER button.
Mode: Playback (FWD)
test tape
WS-48B
(3 kHz, 0 dB)
set
1. Insert the WS-48B into the deck A and the blank tape into the
deck B.
2. Press the REC button and · button on the deck B. Then
the deck B is at recording mode.
3. Set the deck A to playback mode.
4. Keep pressing the HIGH SPEED DUBBING button in play-
back mode.
Then at HIGH speed mode.
5. Adjust RV652 on the AUDIO board do that frequency counter
reads 6,000 ± 60 Hz.
6. Take off the HIGH SPEED DUBBING button.
Then at NORMAL speed mode.
7. Adjust RV651 on the AUDIO board so that frequency counter
+30
reads 3,000 Hz.
–10
8. Frequency difference between deck A and deck B the beginning
of the tape should be within ± 1.5%.
Adjustment Location: AUDIO board
Playback level Adjustment DECK A
Procedure:
Mode: Playback (FWD)
test tape
P-4-L300
(315 Hz, 0 dB)
set
Deck A is RV311 (L-CH) and RV411 (R-CH), Deck B is RV301 (L-
CH) and RV401 (R-CH) so that adjustment within adjustment level
as follows.
Adjustment Level:
CN207 PB level: 301.5 to 338.3 mV (–8.2 to –7.2 dB) level
difference between the channels: within ±0.5 dB
Adjustment Location: AUDIO and main boards
– 31 –
frequency counter
+
–
main board
CN207 (Pin 1 : L-CH)
(Pin 3 :R-CH)
DECK B
level meter
+
–
main board
CN207 (Pin 1 : L-CH)
(Pin 3 : R-CH)