JVC CA-MXKB22, Руководство по обслуживанию

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(No.MB306)1-29
4.3 Cassette amp section
4.4 Tuner section (B/EV version)
Item Measuring condition Check and adjustment procedure Standard value Adjusting part
Head azimuth
adjustment
Tape speed and
wow/flutter check
and adjustment
2940 to 3090 Hz
within 0.35%
(unweighted)
Motor semifixed
resistor
Tape speed
Check only
1. Playback the test tape VT712 by the end
portion.
2. Connect a frequency counter and check that
it reads between 2940 and 3090 Hz. If not,
adjust the frequency with the motor
semifixed resistor.
3. Check that the wow/flutter is within 0.35%
(unweigthed). Test tap : VT712
Signal output terminal :
SPK out
(with 6 ohm load)
Rec anf PB
frequency
response
adjustment Level difference for
1 kHz signal :
within (0+3dB-6dB) Record the reference CD 1 kHz signal and 10
kHz signal alternately repeatedly. While playing
back the recorded signal of the 1 kHz signal
doffer from that of the 10 kHz signal by within
(0+3dB-6dB). Test tape : Brank tape
Signal input :
CD 1 kHz -20 dBs
Signal output terminal :
SPK out
(with 6 ohm load)
Bias frequency
chek Level difference for
1 kHz signal :
within (0+3dB-6dB) Set the Tuner or CD function and with TAPE
to record check to see if the frequency at the
measuring point REC-IF is 85 kHz if not adjust
T100 until the frequency counter indicates
85 kHz+1kHz-1kHz. Test tape : B
Signal output terminal :
Cassette REC/Play
head
Output level :
Within (2 dB of
Maximum output
level.
*Phase difference
R and L channels :
Minimum Head azimuth
adjusting screw
(To be use only
after head
replacement) Test tape : VT703L
Signal output terminal :
SPK out
(with 6 ohm load) 1. Playback the test tape VT703L.
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 (20dB 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 maladjusting
correct it with the head azimuth adjusting
screw.
Item Measuring condition Check and adjustment procedure Standard value Adjusting part
AM IF adjustment
AM tracking
adjustment IFT605
IFT601
IFT606
VC606
L604
L605
VC604
1. Set the TUNER at 522 kHz adjust IFT605
until the test point TP4 voltage at 1.3V+/-.1V.
2. Set the TUNER at 1629 kHz, check the test
point TP4 voltage at 7.0 to 8.0 V.
3. Set the TUNER and S/G at 600 kHz, adjust
ITT606 for maximum output.
4. Set the TUNER and S/G at 1500 kHz, adjust
the VC606 for maximum output.
5. Repeat the avobe step 3 and 4. Signal input :
Loop antenna
signal output :
H.phone out
(with 32 ohm load)
Signal input :
Analog antenna
FM ANT
Fm GND
signal output :
H.phone out
(with 32 ohm load) FM tracking
Signal input :
Loop antenna
Signal output :
IC602 pin 16 1. Set the intermediate frequency sweep
generator to AM 450 kHz.
2. Adjust IFT601 for maximum and center
output
1. Set the TUNER at 87.5MHz adjust L604 until
the point TP5 voltage at 1.5V+/-0.1V.
2. Set the TUNER at 108MHz, check the point
TP5 voltage at 7.2-8.0V.
3. Set the TUNER and S/G at 90.1MHz, adjust
L605 for amximum output.
4. Set the TUNER and S/G at 106.1MHz, adjust
the VC604 for maximum output.