Panasonic HCD-D670AV Service Manual page 12

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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 1 dB of peak.
L-CH
peak
output
within
level
1dB
R-CH
peak
screw
position
3. Mode : Playback (FWD)
test tape
P-4-A100
(10kHz, –10dB)
TE
L 13942296513
set
Waveform of oscilloscope
45 °
in phase
good
4. Repeat steps 1 to 3 in playback (REV) mode.
5. After the adjustments, apply suitable locking compound to the
parts adjusted.
Adjustment Location : Record/Playback Head (Deck A and B)
www
FWD side
.
Adjustment screw
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within 1dB
screw
L-CH
R-CH
position
peak
peak
main board
CN403
Pin 3
oscilloscope
Pin 2
L
R
Pin 1
90 ° 135 °
180 °
wrong
x ao
y
REV side
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8
Tape Speed Adjustment DECK A
NOTE : Start the tape speed adjustment as bellow after setting the
test mode.The tape speed can be changed with the HIGH
SPEED DUBBING button during the test mode.
Method :
1. Turn the power switch on.
2. Press the DISPLAY/DEMO button, MENU 1 button and TUNER/
BAND button simulateously.
Procedure :
Mode : Playback (FWD)
test tape
WS-48B
(3kHz, 0dB)
set
1. Insert tha WS-48B into the deck A to playback.
2. Press the HIGH SPEED DUBBING button. Then at HIGH
SPEED mode.
3. Adjust RV652 on the MD board so that the frequency counter
reading becomes 6,000 ± 30 Hz.
Q Q
3 6 7 1 3
4. Press the HIGH SPEED DUBBING button again to be set the
NORMAL SPEED mode.
5. Set to the playback mode.
6. Adjust RV651 on the MD board so that the frequency counter
reading becomes 3,000 ± 15 Hz.
Frequency difference between deck A and deck B the beginning of
the tape should be within ± 1.5%.
Adjustment Location : MD board
Playback Level Adjustment DECK A
Procedure :
Mode : Playback (FWD)
test tape
P-4-L300
(315Hz, 0dB)
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 the following
adjustment level.
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Adjustment level :
CN403 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 : MD board
— 12 —
2 9 9 4 2 8
frequency counter
main board
CN403 (Pin 3 : L-CH)
(Pin 1 : R-CH)
1 5 0 5 8 2 9 9 4
DECK B
level meter
main board
CN403 (Pin 3 : L-CH)
(Pin 1 : R-CH)
m
co
9 9
2 8 9 9