JVC CA-PCX290, Руководство по обслуживанию

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8
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Cassette Amplifier Section
Item Measuring Condition Check and adjustment procedure Standard value Adjusting part
Head azimuth
adjustment
•
Test tape:
MTT113CN (8 kHz)
•
Signal output
terminal:
PHONES
(with 32 ohm load)
1. Play back the test MTT113CN (8 kHz).
2. Adjust the head azimuth adjusting screw so that
the phase difference between the R and L
channels is minimized at an output level that is
within ±2 dB of the maximum output level . After
this adjustment, lock the head azimuth adjusting
screw with screw sealant to cover more than a
half of the screw head.
3. When the head azimuth is maladjusted, correct it
with the head azimuth adjusting screw.
•
Output level:
•
Within ±2 dB of
maximum output
level
•
Phase difference
L and R
channels:
Minimum
Head azimuth
adjusting
screw (To be
used only
after head
replacement)
See Fig 3-1
PB frequency
response check
•
Test tape:
MTT257C
•
Signal output
terminal:
PHONES
(with 32 ohm load)
Play back the test tape MTT257C while con-firming
that deviation between the 1 kHz signal and 8 kHz
signal should be 0 (+3~-6) dB.
Deviation between
1 kHz and 8 kHz:
0 (+3~-6) dB
Bias frequency
check
•
Tape: Normal
•
Signal output
terminal: Cassette
REC./PLAY HEAD
Set the TUNER or CD function and with TAPE to
record. check to see if the frequency at the
measuring point R201 or R202 is 82 kHz ±1 kHz. if
not adjust L203 until the frequency counter
indicates 82 kHz ± 1 kHz.
L203,
R201/R202
See Fig 3-2
REC and PB
frequency
response
adjustment
•
Test tape: MTT-501
•
Signal input FM22.5
DEV 60dB
µ
with
Emphasis
•
signal output
terminal: PHONES
(with 32 ohm load)
At TUNER, set the BAND to the FM position, and
record the reference 1 kHz signal and 8 kHz signal
alternately repeatedly. While playing back the
recorded signal differ from that of the 1 kHz signal
by within 0 (+3~-6) dB.
Level difference
between REC and
PB:Within 0 (+3~-6)
dB.
PC - X290