JVC QL-A2 Service Manual

8. Cartridge Replacement
. Unscrew the connector nut to remove the headshell.
2. Remove the two long screws on the headshell which
hold the cartridge.
3. Connect the lead wires of the headshell to the new
cartridge, being careful to match the polarities correctly.
Polarity and wire colors are as follows:
White (+) ....L Red (+)...... R
Blue (-) ..... LE Green(-) .... RE
4. Attach the cartridge to the headshell squarely, and
gently tighten the screws.
5. Set the cueing lever to “DOWN”, and then bring the
stylus tip to the overhang indicator by sliding the
cartridge back and forth.
After the adjustment, fix it firmly.
6. After attaching the cartridge, slide the headshell into
the tonearm with the connector pin fitting in the groove.
Tighten the connector nut.
_
9,
Adjustment
Procedures
7.
Be
sure
to
adjust
the
tracking
force
and
lead-in
position
after replacing the cartridge.
Screw
Plastic
washer ?
4 A Headshell
R “—
Cartridge pin—___ {4
Cartridge
body
~~
!
ue
Stylus
_ Groove
Connector pin
Headshell
Connector nut
Fig. 12
Fig. 13
Servomotor Control Section
9-(1)
Power
Supply
Voltage
Check
1.
Disconnect
the
motor
socket
from
the
circuit
board.
Turn
the
power
switch
on.
(Confirm
that
the
rated
voltage
is
applied
to
the
unit.)
Confirm
that
22
+0.5
V
DC
is
present
at
TP-5.
If
the
voltage
is
deviate
from
that
range,
adjust
with
the
semi-fixed
resistor
VR803
(1
k{2).
2.
Confirm
that
the
voltage
difference
at
TP-5
is
less
than
-1V
when
the
platter
is
stalled
with
hand.
9-(2) Lock Adjustment
1) With dual beam oscilloscope
1. Connect the motor socket to the circuit board. Connect
the dual beam oscilloscope to TP-3, TP-4. Obtain a
turntable speed of 45 rpm by setting the speed select
switch
to
45
and
turn
the
power
switch
on,
then
adjust
the
semi-fixed
resistor
VR802
(100
k{Q2)
until
the
follow-
ing waveforms are obtained.
14.8 ms (20ms)
ee
Fig. 14
Adjust to get a difference of within + 1 msec from TP4.
2. Obtain a turntable speed of 33-1/3 rpm by setting the
speed select switch to 33-1/3, then adjust the semi-
fixed resistor VR801 (47kQ) until the difference
between TP-3 and TP-4 is within + 1 msec.
2) With single beam oscilloscope
Connect
the
single
beam
oscilloscope
to
TP-3,
TP-4
as
shown
in
Fig.
15
below.
Adjust
until
the
waveforms
shown
in
Fig.
16
are
obtained.
The
allowable
deviation
for
adjustment
should
be
within
1
msec.
as
shown
in
Fig.
16,
Fig.
17.
Connection
diagram
Ma imMn TPS
TP-3
Precaution
if the measurement As
of TP-3 is required,
connect the output
of test equipment to
TP-3 through 10 kQ
resistor.
Single beam oscilloscope
Within 1 msec
Fig. 15
Fig. 16
Ov
Within 1 msec
=e
Fig. 17
Ov
QL-A2
No, 244
F
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4

JVC QL-A2 Specifications

General

Brand	JVC
Model	QL-A2
Category	Turntable
Language	English