JVC QL-5 User manual

JVC
MODEL
QL'5
aie DIRECT DRIVE
TURNTABL
No. 2428
NOV. 1977

Contents
1. Specifications ....
2. Service Precautions . é
3. Features ........ z
: : 3
4. “How to Operate” (Names & Functions) 3
5. Block Diagrams
BAT)
Servomiotor
Control
Syste
aee:ciciwreiasis
Hops
auseaw
nae
Maisie
waresinseedyae
alt
4
5-(2)
1802
Integrated
Circuits
and
Waveforms
..........-200
cs
eeee cece
eens
5
6. Troubleshooting
6-(1)
Platter does not rotate
6
6-(2)
Platter
rotates
at
a
high
speed
.......
--
6
6-(3) Rotation is not locked to the crystal oscillator frequency .............00-0 000 7
7. Parts Replacement
TU):
:
Stylus
Rap
lacehieNnt
«aa
setviecestwoeanciidvisn
vk
ids
thea
mews
SOLAR
¥
8
FA)
Cartridge
Replacdenent’S<.075,5.5:5-a0«,aysip-ee
65
Sate,
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s
8
8. Adjustment Procedures
Servomotor Control Section
8-(1)
Power
Supply
Voltage
Check
2
9
8-(2) Lock Adjustment F og:
8-(3)
Brake
Mechanism
Adjustment
.............00-
00
ccc
eee
ceecceecceuceas
10
Tonearm
Section
8:(4))
Tonsatin:
Height
Adpistnetitecc.
via
catia
Loa
5G
Pisww
US
Fa
Sk
NOES
ad
Mees
8-(5) Arm Lifter Height Adjustment..............
8-(6)
Overhang
Adjustment
8-(7)
Headshell
Angle Adjustment
8-8)
Tracking
Force Adjustment
a
8-(9)
Anti-skating
Adjustment
.................
8-(10)
Arm-rest
Height Ajustment
9. Lubrication
cccncawes
cis ve esevee
10. Exploded
Views and Parts List
10-(1)
Servomotor
Control
and
Cabinet
Ass'y
............
10-(2)
Parts
List
with
Specified
Numbers
for
Designated
Areas
.
IONS),
TONDSNTAR’Y
o.2.5:5.
sraieiciain
srecarcaie
aaavare
wie
eitelab
alieaels
du
reus
ate
ECW
os
DEB
11. Printed
Circuit
Board Ass’y and Parts List
11-(1)
TXX-101
Servomotor
Control
P.C.
Board
Ass’y..
2.0...
eee
ee
eee
eee
11-(2) TSC-80F
(GBS) Power Supply
P.C. Board Ass’y . .
12.
Schematic
Diagram
....
2.2...
2000
eee
e
cece
eeeeee
13.
Packing
Materials
and
Part
Numbers
.
14. Accessories
List . .
CHECKING
YOUR
LINE
VOLTAGE
(For
U.S.
Military
Market
and
Other
Countries)
Before
inserting
the
power
plug,
please
check
this
setting
to
see
that
it
corresponds
with
the
line
voltage
in
your
area.
If
it
doesn’t,
be
sure
to
adjust
the
voltage
selector
switch
to
the
proper
setting
before
operating
this
equipment.
The
voltage
selector
switch
is
located
either
on
the
set’s
on
the
chassis.
Simply
insert
a
screw
driver
into
the
voltage
selector
switch
and
turn
it
in
either
direction
while
pressing
slightly
and
in
such
a
way
that
the
desired
voltage
marked
on
the
switch
is
positioned
underneath
the
arrow
marked
on
the
rear
panel
or
the
chassis.
The
voltage
selector
switch
accom-
modates up to three turns in either direction.
OL-5
No.
2428
—1—

1. Specifications
Motor section
Motor
Drive system
Speeds
Wow and flutter
Rumble
Speed
detection
Starting
torque
Speed
deviation
Load
characteristics
Drift
per
hour
Power
characteristics
Temperature
characteristics
Platter
Quick
stop
time
Tonearm
section
Type
Effective length
Tracking error
Overhang
Tracking force range
Weight range (including headshell)
Height range
Mechanisms equipped
: 12-pole, 24-slot, DC type FG servomotor
: Direct drive
: 33-1/3 and 45 rpm
: Less than 0.025 % (WRMS)
: More than 63 dB (IEC-B)
More than 73 dB (DIN-B)
: Integrated frequency generator
: More than 0.8 kg-cm
: Within 0.004 %
: 0 % (with 100 g total tracking force)
: 0.0001 %/H
10% (+ 10 %)
: 0.00005 %/°C
: 31.2 cm diameter
: Within 1.6 seconds
: T.H, (Tracing-Hold system, static balance), New Gimbal
Support
2245 mm
:+1°48" -1°31'
215mm
:0—34g (0.25 grams division, direct reading)
: 14.5 — 22 g (Headshell 10 g)
: 39 — 51 mm (present to 43 mm)
: Oil-damped arm elevator
Anti-skating system
Headshell mounting angle fine adjustment possible
Cartridge section (not provided on units for U.S.A., Canada and the U.K.)
Type
Stylus
Optimum tracking force
Output
Frequency response
Separation
Load Resistance
Compliance
General
Dimensions
Weight
Power
Specifications
: Moving Magnet (Cartridge body: MD-1025)
:0.3
x
0.7
mil.
diamond
(DT-Z1TE)
:2 grams
:3
mV
(1
kHz)
: 10 to 25 000 Hz
: More than 25 dB (1 kHz)
(with test record TRS-1)
: 47 k ohms
:10 x 10° cm/dyne (Dynamic)
30 x 10° cm/dyne (Static)
: 16.5 (H) x 48.1 (W) x 40.3 (D) cm (with cover closed)
(6-1/2” x 18-15/16" x 15-7/8")
(Since the dimensions show only the design
measurements, consideration is required when
installing the unit in a limited space such as a rack.)
2
10.5
kg
(23.1
Ibs)
(without corrugated cardboard case)
Countries
U.S.A. & CANADA
CONTINENTAL EUROPE
U.K. & AUSTRALIA
U.S. MILITARY MARKET
OTHER AREAS
Line Voltage & Frequency Power Consumption
AC 120 V, 60 Hz 12 watts
AC 220 V, 50 Hz 12 watts
AC 240 V,50 Hz 12 watts
AC 110, 120, 220, 240 V |
Selectable, 50/60 Hz | twats
|
AC 110, 120, 220, 240 V
Selectable, 50/60 Hz Tewari
QL-5
No. 2428

2. Service Precautions
1.
Be
sure
to
place
the
unit
on
a
level
surface
when
adjust-
ing motor rotation.
.
In
servicing,
do
not
use
parts
other
than
those
specified.
. Be careful
not to damage
the motor shaft when repairing
the motor unit.
4.
When
the
heatsink
(including
X820)
is
removed
from
the motor board to permit
repair of the citcuit board,
the transistor
temperature
may increase
due to the lack
ON
3. Features
@ Quartz-locked speed control system
@
FG
servomotor
assures
optimal
torque
(starting
torque
0.8 kg-cm).
© Heavy aluminum die-cast platter of 2 kg cover included
Inertia mass 280 kg-cm?.
of heat radiation, Attach an aluminum plate (approx.
100 (W) x 100 (D) x 1 (H) mm to the motor board).
If noise is produced when the knobs are turned or re-
placed, apply white grease or a small amount of silicon
(50 000 unit, a quarter of a drop) on the knob shafts
and the moving parts of the spring.
Note: Resin of the knob may be damaged if lubricating
oils other than those specified are used.
Cartridge it elliptical stylus employed. (Z-1TE)
Quick stop mecanism equipped.
Highly sensitive, New Gimbal Suppot Tonearm with an
effective length of 245 mm employed.
4.
“How
to
Operate”
(Names
and
Functions)
POWER switch
Turn
the
power
switch
ON.
Stroboscope
lamp
lights.
Speed select/STOP knob
Turn the knob to align the index line on the knob
with “33” or “45”, depending on the rpm of the
record you wish to play.
33-1/3 rpm record (LP) . .. "33"
45 rpm record (EP) .... ae “45%
The
platter
stops
within
one
revolution
when
the
index
line
is
aligned
with
the
“STOP”
position
centered between the “33” and “45” positions.
Anti-skating knob
The
anti-skating
mechanism
counteracts
the
centripetal
force
which
pulls
the
stylus
towards
the
center
of the
record
while
the
record
is
playing;
thereby
reducing
the pressure
on the inner
walls
of the record
groove.
Arm lifter lever
Raise
the
lever
to
lift
the
tonearm, and lower it for
the tonearm to descend
gently.
Stroboscope pattern
A single stroboscope pattern is equipped on the
rim
of
the
platter.
When
the
turntable
rotates
at
either
33-1/3
or
45
rpm,
the
pattern
will
appear
Stationary to indicate that the turntable speed
is correct.
No. 2428

5.
Block
Diagrams
5-(1)
Servomotor
Control
System
Platter
Waveform
shaper
50 Hz (at 33-1/3 rpm)
67.5
Hz
(at
45
rpm)
Frequency
generator
Quick-stop
brake solenoid
Power switch
Inez
Power Ise
supply
1235]
G59-504
MHz
circuit
ese
Quartz
crystal
lou
Speed select
ignal
Ac
Speed select/
ON-OFF switch
45 STOP 33
< =
Fig. 2
QL-5
ayy es No. 2428

5-(2)
1C802
Integrated
Circuits
and
Waveforms
Vss
Po
P:
Pz P3
P4
P5 P6
P7
20127
TOP
VIEW
voo[
|o
vss
Qin
PO
Voo
it
5
@
ouT
Pt
Qin
@
v3
10
STAGE
PROGRAM
COUNTER
AN
FG
IN
P2
Qour®
1
Fvs
o
2
P3
TIMING
2
s
GENERATOR
RPG
Fvc
Pas!
P4
&
a
Ld
sT
Fv
a
a
PS
>
a
Fon
SAMPLE
-HOLD
PDS
ko
P6
Le
PDB
P7
|
POC
ST
PD
20/27
~O-©)—
FVs
FVc
DATE
CODE
Fig.
3
Block
Diagram
Fig.
4
Pins
Location
na
0
19
From
oe
oo
Mo
oo
Mo
Bo
|
SM64ISA-4
°
Lo
‘i
7
7
aev
nav
20ms
ADB
Fig.
5
Waveforms
(Pin
1
through
Pin
11)
F/V
section
P/D
section
1
Waveform
at
pin
4,
=
Waveform
at
pin
8,
|
5v
i}
V2
'
ac
1
ft
Waveform
at
pin
5,
f
Waveform
at
pin
11.
epliie
i
|
lv
i
H
Approx.
1.7
Vat
33-13.
1
|
Be
sure
to
obtain
I
the
waveform
H
|
at
pin
13
through
1
Waveform
at pin 7.
R845,
otherwise
l
i
Vi-Vess
the
IC
may
be
{
=
damaged.
Deviation
at
lock
adjustment
|
Approx.
2.7
V
at
33-1/3.
(this
should
be
within
+
1
msec.)
Fig. 6 Waveforms (F/V and P/D)}
ols
No. 2428 = =

6. Troubleshooting
6-(1) Platter does rotate
C Roration is not locked to the crystal oscillator frequency. )
Are the pulse
Fectanguler
waveforms
of
50
Hz
and
67.5
Hz
available at pin 5 of
1C803?
Is the 9.504 MHz
oscillation voltage present
at pin 3 of 10802?
Yes
Is adjustment
with VR801 or VR802
effective?
Is about normal
rotation obtained with
R818 removed?
Are C805, VR8O1
and
VR802
correctly
employed?
Readjust__ following
justment procedure”.
C809, D801, C810, R815 or
1C802 detective
Replace.
Check 1C802 for defect,
C812 or C813 for discon
nection or pattern-cut.
816, R845 or 1C802
defective. Replace.
6-(2) Platter rotates at a high speed
C Platter rotates at a
igh speed. D)
Does rotation stop.
when pin 1 of IC803
is connected to ground?
Does rotation stop
when +23.0 V is applied
to the base of transistor
X805 or X806?
Yes
Transistor X804, X805 or
X806 is short-circuited be-
tween collector and emitter.
Apply +23.0 V to the base
of transistor X805 or X806
and stop operation of the
drive circuit.
Is FG output
4 mVp-p present
when the platter is rotated
by hand at about
3-1/3 rpm?
Trnasistor X803_ is short-
circuited between collector
and emitter.
Broken connecting wires or
faulty soldering.
Check for broken patterns
or faulty soldering
is 2 Vp-p output
present at pin 7 of
1801 when the platter
is rotated by hand at
about 33-1/3 rpm?,
Is
23.0
V
available
at
pin
8
of
IC801
Is the waveform
present at TP-3 as shown
in wiring diagram 1?
Yes
Check connection or solder
ing of 1C802.
Is FG output as
specified?
Is
2
Vp-p
output present at
7 of 10801?
Check motor or replace
1801
Is the rectangular
waveform of 23 V at
pin 1 of C801 available
when the platter is rotated,
by hand at about
33-1/3 rpm?
1801 defective
Is the rectangular
waveform of 4.5V at
TP-3 available when the
platter is rotated by hand
at about 33-1/3 rmp?
Is about
DC2.7 V available
at pin 7 of 1C802 when
at about 33-1/3 rpm?
the platter rotated by hand,
Is about
0010.9 V
available at pin 1 of
1C803 when the platter
is rotated by hand at
about 33-1/3 rpmz,
Check for defective 1C801 or
incor capacitance of
C808.
Check for broken pattern or
faulty soldering of R808 and
R809.
Check for defective 1C802,
short-circuited
or
open
leads.
1c
Check
for
defective
1C803,
short-circuited or open
leads.
IC
Yes
|
Detective |C801, incorrect
capacitance of C801 or open
R803 may be the cause.
Normal
QL-5
No. 2428

QL-5
No. 2428
Is23-0.5V
available at TP-5 when the.
Platter does not rotate.
Yes
power switch S3 is
turned on?
1s a voltage present at the
collector
of
transistor
X8172,
1s an AC voltage present
between lapping tabs 7 — 8,
Primary fuse or transformer
disconnected. AC cord
soldering defective.
Yes
Transistor X817 — X819 or
diode D811 defective.
Diode 0812 — D815 open or
incorrectly soldered
Hall elements open. Motor No
disconnected inside, dis.
connected resistors,
Yes
Does the platter rotate when
6-(3)
Rotation
is
not
locked
to
the
crystal
oscillator
frequency
R820 is short-circuited?,
Does platter rotate
when pins 6 and 1 of 1C802
are short-circuited?
Does the platter rotate
‘when
pins
1
and
8
of IC
803
are short-circuited?
IC8O3 defective
1C802 defective.
Does platter rotate
Yes
transistor X803 are
short-circuited?
Transistor ¥803 is open be-
tween emitter and collector.
Does platter rotate by hand?
1s output available
St voltage terminals of Hall
elements HG-1 and HG-2?,
Transistors X807 — X814
detective. Lead from circuit
board to motor disconnected.
Check for loose socket,
floating pattern
fective soldering
and de
Yes Check for incorrect ca
pacitance or defective solder
ing of 1C801.
Is the oscillation waveform
available at TP-3?
Is transistor X815,
capacitor C818, resistor
R847 of R848 not
defective?
Yes
Replace
defective
part.
Notes for replacement of transistors X811 — X814
There are 4 ranks K1, K2, L1 and L2 for 2 SD571
transistor h FE. Be sure to use those transistors of the same
ranking when replacing.

7. Parts Replacement
7-(1) Stylus Replacement
Replacement of the stylus can be easily made by simply
inserting the stylus plug (A) into the jack (B) of the
cartridge.
Service life of the stylus employed for this unit is generally
as follows, varying, depending on the record conditions:
(dirty record groove etc.).
Stereo LP record (30 cm)
Approx, 300 — 500 hours
Styli are disposable items.
Therefore, it is recommended to buy a supply of styli
when you buying the unit. When purchasing them, specify
the DT-Z1TE (JVC, standard). Styli approximating
DT-Z1TE
are
available
on
the
market.
Usage
of
such
styli
may result in a noisy and distorted sound reproduction. Be
careful to avoid their usage.
Note: Cartridge is not provided on units for the US.A.,
Canada and the United Kingdom.
7-(2) Cartridge Replacement
Removal
and
mounting
of
the
headshell
(Fig.
8)
Turn
the
connector
nut
in
the
direction
of
“A”
to
remove
the
headshell
from
the
tonearm.
Turn
it
in
the
direction
of
“B"
for
mounting
the
headshell.
Cartridge replacement (Fig. 9)
1. Remove the 2 screws securing the cartridge on the
headshell.
2.
Reinstall
a
cartridge
onto
the
headshell.
3.
The
four
cartridge
lead
wires
are
colour-coded
as
follows:
Connect
them correctly.
White (+) .
Blue (-)..
Red (+) .
Green (—) .
4. Mount the cartridge properly onto the headshell and
leave the set screws slightly loosened, then, after
completing the “‘Overhang adjustment”, tighten them
firmly.
5. After each cartridge replacement, be sure to perform
tracking force and overhang adjustments.
Note: If a heavy cartridge or headshell is employed, ‘Zero
balance’’ may not be obtained with the specified
counterweight.
In this case, use an optional counterweight.
(SW-71,
for
cartridge
of
14.5
~
22g
including
head-
shell)
(SW-37,
for
cartridge
of
24
~
37
g
including
head-
shell)
Stylus
Tonearm
fw
Connector nut
Headshell
Fig. 8
Cartridge securing ——T
®
=
Headshell
Blue (LE)
White (L)
Green (RE) er
UY
Red
(R)
‘a
Cartridge e Se. Nut
Cover pe
Fig. 9
QL-5
No. 2428

8.
Adjustment
Procedures
Servomotor Control Section
8-(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.) Set the speed select
switch to 33-1/3. Confirm that 23 + 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 speed select/on-off switch is set at
STOP.
8-(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, then adjust the semi-fixed resistor VR801
(100 kQ) until the following waveforms are obtained.
1
14.8ms
(20ms))
co...
! i
1 IL
oo ls
~at—
Adjust to get a difference of within + 1 msec from TP-4,
Fig. 10
2. Obtain a turntable speed fo 33-1/3 rpm by setting the
speed select switch to 33-1/3, then adjust the semi-
fixed resistor VR802 (47k) until the difference
between TP-3 and TP-4 is within + 1 msec.
QL-5
No. 2428
2) With single beam oscilloscope
Connect the single beam oscilloscope to TP-3, TP-4 as
shown in Fig. 11 below. Adjust until the waveforms shown
in Fig. 12 are obtained.
Connection diagram
TP-3)
ma Ma
TR=4
Single beam oscilloscope
Fig. 11
Perfectly locked
|
|
Lock
adjustment
is
improper.
Out of lock in the direction
opposite to the diagrams above,
Out of lock
This
part
appears
to
flow.
Fig. 12