JVC CA-C55BK - Cassette Deck Adjustment Procedures; Measuring Instruments and Torque Checks; Head Azimuth and Torque Adjustments

DX-C55BK
Adjustment Procedures (Cassette Deck)
1. Measuring instruments
Audio frequency signal generator ( Odbs output at the 600 ohm output terminal from 50Hz to 20KHz)
Electronic voltmeter
Frequency counter
Wow & Flutter meter
Distortion Meter with band pass filter
Attenuator (600 ohm impedance)
A resistor with 6000
Standard Tape
Ww
SA
Head
azimuth
i Wow
&
flutter
2-12 (No.20474)
[aera
2. Adjustment and repairing
Deck A
ic
2.
3.
Connect an electronic voltmeter to the DOLBY
TP(figure 3) to playback VTT-703L.
Adjust screw © so that the indication of the
voltmeter becomes maximum when PLAY (P) is
pressed.
Adjust screw © so that the indication of the
voltmeter becomes maximum when PLAY () is
pressed.
Deck B
4.
Ds
6.
1.
2.
Adjust screw © so that the indication of the
voltmeter becomes maximum when PLAY (P)
is pressed.
Adjust screw © so that the indication of the
voltmeter becomes maximum when PLAY (<<)
is pressed.
After making the adjustment,apply screw Sock to
prevent screws © ,®,©@and © coming loose .
Connect the wow & flutter meter to the
DOLBY TP(figure 3) and play back VTT-712.
Its reading should be within 0.2% (WTD).
® ®
Deck A
the mechanism
Figure 1
Maximum
Playback 1. Measure the torque in the playback mode by 26 ~ 62 [When the standard torque cannot be obtained,
torque the torqu meter. g-cm replace the FR arm assembly or motor.
Fast forward |1. Measure the torque in the fast forward mode | 80~170 |When the standard torque cannot be
torque by the torqu meter. g-cm obtained,replace the FR arm assembly or motor.
Rewind 1. Measure the torque in the rewind mode by 80~ 170 |When the standard torque cannot be
torque the torqu meter. g-cm obtained, replace the FR arm assembly or motor.
As a complaint may occur if the wow & flutter |
fluctuates by 0.1% even though it is allowed
in the standard, repairing is required.
1. Refer to figure 1.
2. When the specified characteristic cannot be
. When there is the difference of more than
OdBs = 0.775V
obtained because of head wear, excessive
magnetization, etc., replace the head
assembly and adjust the head azimuth.
Also, perform the electric adjustment.
3~ 4 dB between left and right output
levels, replace the head assembly to avoid
complaints.
Deck B