Service Precautions; Names And Their Functions - JVC QL-Y5SF Service Manual

2. Service Precautions
1;
For repair of the tonearm, only the parts whose names
and numbers are listed on page 17 are replaceable. So be
careful not to remove any other part.
. For repair of any component other than the tonearm,
be sure to perform part replacement in accordance with
the appropriate unit of the block shown in the dis-
assembly diagram.
. When remounting the motor base or tonearm ensure
positive contact with the base of the.tonearm (as shown
in Fig. 14B) and then secure.
. Ensure that the turntable is level when servicing motor
rotation or arm action.
3. Names and Their Functions
(2)
0 °@o
SIZE indicator (30)
SIZE indicator (17)
QUARTZ LOCK indicator
SPEED indicator (33)
SPEED indicator (45)
Fig. 2
. Tonearm
This tonearm is called'an Electro-Dynamic Servo Tone-
arm. All the functions, the tracking force, anti-skaing,
Q-damping, etc. are done electrically.
. SPEED switch
Select the speed depending on record rpm. The platter
rpm is indicated by the SPEED indicators.
. SIZE switch
Select the size depending on record size. Selected size
is indicated by the SIZE indicators.
. START/STOP switch
Press this switch to rotate the platter. When the speed
reaches normal, QUARTZ LOCK indicator (green)
lights. Then the tonearm automatically lifts up and
moves to lead-in.
. READY switch
ON: Depress this switch to power the turntable system
on. SPEED and SIZE indicators light. Stylus
force, anti-skating and Q-damping are automati-
cally applied, as already set.
OFF-ARM BALANCE: Re-depress the switch to cut
the power off. The SPEED, SIZE and QUARTZ
LOCK indicators go out, and the stylus force,
anti-skating and Q-damping become "'zero".
10.
11.
. If power is applied when the motor connector is discon-
nected the drive transistor will be damaged. Therefore,
never disconnect the motor connector if the power is or
will be applied.
. Note that when repairing the printed board, if the heat-
sink is removed, transistor temperature will rise.
. Upon completion of repair or replacement of the tone-
arm, motor or any other component, be sure to perform
Lead-in and Lead-out adjustments.
. Locating the tuner antenna and the turntable output
lead closely may cause noise due to disturbance from the
tuner; therefore, place them as far from one another as
possible.
Note: When you re-depress the READY switch, make
sure the tonearm is clamped on the arm rest,
otherwise you may damage a record or the stylus.
Even when the READY switch is set to OFF,
about 1 watt power is consumed. Accordingly,
disconnect the power cord from wall outlet to
cut the power completely off.
. Q-DAMPING knob
This knob is provided to smoothen stylus tracing hori-
zontally and vertically along with the record disc
grooves and to effectively lower the resonance peak
levels of the tonearm. When Q-DAMPING is in opera-
tion:
1. Trackability and sound quality are improved,
2. Resistance against howling is much increased,
3. S/N ratio and wow-and-flutter are improved, etc.
. ANTI-SKATING TRACKING FORCE knob
This knob is provided to cancell the centripetal force
(sliding of the tonearm to the center of the record)
and to prevent the stylus tip from sliding or exerting
unwanted force to the inner side of the record groove.
These are automatically and electrically set to the
optimum value by selecting the designated stylus force.
. UP/DOWN switch
When this button is pressed the tonearm will lower to
the record surface, then the UP/DOWN indicator goes
out, Pressing this button again will cause the tonearm
to lift up from the record and the UP/DOWN indicator
will come on.
. UP/DOWN indicator
This indicator lights when the tonearm lifts up and
goes out when it is lowered. This does not light during
lead-in, reject or auto-return.
Tonearm transport switch
The tonearm can be moved manually or can be moved
to any position of the record surface by pressing the
following buttons.
<: depressing this button will move the tonearm to
the left, releasing it stops travel.
>: depressing this button moves the tonearm to the
right, releasing it stops travel.
REPEAT switch
Depress this button for repeated play.
The REPEAT indicator lights to show that the REPEAT
setting has been made. Press again to release the
REPEAT function. The indicator will go out.
QL-Y5F
No. 2522