SERVICE MANUAL
CORDLESS FM STEREO HEADPHONES
No.70270
Sep. 2002
COPYRIGHT
2002 VICTOR COMPANY OF JAPAN, LTD.
HA-W500RF (EG)/(EK)
HA-W500RF (EG)/(EK)
Specifications
* Design and specifications subject to change without notice.
Transmitter (J22121-001)
Power requirements
: DC 9 V (with the exclusive AC
adaptor J47126-001(EG Model)
/J47127-001(EK Model))
Audio input ter minal
: 3.5 mm dia. stereo mini plug
Input impedance
: 25 k
Reference input level : 300 mV
Dimensions
: 100(W) x 100(D) x 106(H) mm
(3-15/16" x 3-15/16" x 4-3/16")
(Including antenna)
Mass
: 115
(4.1 oz)
(Without connection cor d and AC
adaptor)
Provided Accessories
Instructions
x 1
AC adaptor
x 1
Connection cor d x 1 (3.5 mm dia. stereo mini jack-
RCA pin plug x 2 : 0.1 m (0.3 ft))
Plug adaptor
x 1 (converts 3.5 mm dia. stereo
mini plug to a 6.3 mm dia. standar d
stereo phone plug)
General Specifications
System
: Radio Frequency (UHF stereo)
Modulation
: Frequency modulation
Carrier frequency
: 863-865 MHz
Usable area
(distance to reach)
: Approx. 100m (328 ft) : using
JVC measurements systems
Frequency response : 30 Hz-15,000 Hz
Distortion
: Less than 4 % (at 1 kHz)
Contents
Headphones (HA-W500RF)
Power requirements : Rechargeable
Ni-Cd batter y (1.2 V) x 2
Battery running time : 20 hours
(When charged for 24 hours)
Mass
: 280
(9.9 oz)
(With installed rechargeable
Ni-Cd batter y x 2)
Specifications ------------ Front cover
1. Disassembly ------------------------- 3
2. Schematic Diagram ---------------- 4
3. Measurement Condition --------- 5
4. Print Circuit Board ----------------- 5
5. Wiring Diagram --------------------- 7
6. Block View Inside IC -------------- 7
7. Block Diagram ---------------------- 8
8. Electric Parts List ------------------ 8
9. Exploded view ----------------------- 9
10 .Mechanical Parts List ------------ 9
11. Packing Method ------------------ 10
12. Packing Materials Parts List - 10
13. Accessories List ----------------- 10
HA-W500RF (EG)/(EK)
2 (No.70270)
Safety Precautions
1. This design of this product contains special hardware and many circuits and components specially
for safety purposes.
For continued protection, no changes should be made to the original design
unless authorized in writing by the manufacturer.
Replacement parts must be identical to those
used in the original circuits.
Services should be performed by qualified personnel only.
2. Alterations of the design or circuitry of the product should not be made.
Any design alterations of
the product should not be made.
Any design alterations or additions will
void the manufacturer`s
warranty and will further relieve the manufacture of responsibility for personal injury or property
damage resulting therefrom.
3. Many electrical and mechanical parts in the products have special safety-related characteristics.
These characteristics are often not evident from visual inspection nor can the protection afforded
by them necessarily be obtained by using replacement components rated for higher voltage,
wattage, etc.
Replacement parts which have these special safety characteristics are identified in
the Parts List of Service Manual.
Electrical components having such features are identified by
shading on the schematics and by (
) on the Parts List in the Service Manual.
The use of a
substitute replacement which does not have the same safety characteristics as the recommended
replacement parts shown in the Parts List of Service Manual may create shock, fire, or other
hazards.
4. The leads in the products are routed and dressed with ties, clamps, tubings, barriers and the
like to be separated from live parts, high temperature parts, moving parts and/or sharp edges
for the prevention of electric shock and fire hazard.
When service is required, the original lead
routing and dress should be observed, and it should be confirmed that they have been returned
to normal, after re-assembling.
5. Leakage currnet check (Electrical shock hazard testing)
After re-assembling the product, always perform an isolation check on the exposed metal parts
of the product (antenna terminals, knobs, metal cabinet, screw heads, headphone jack, control
shafts, etc.) to be sure the product is safe to operate without danger of electrical shock.
Do not use a line isolation transformer during this check.
Plug the AC line cord directly into the AC outlet.
Using a "Leakage Current Tester", measure
the leakage
current from each exposed metal parts of the cabinet , particularly any exposed
metal part having a return path to the chassis, to a known good earth ground. Any leakage
current must not exceed 0.5mA AC (r.m.s.)
Alternate check method
Plug the AC line cord directly into the AC outlet.
Use an AC voltmeter having, 1,000 ohms
per volt or more sensitivity in the following manner. Connect a 1,500
10W resistor paralleled by
a 0.15 F AC-type capacitor between an exposed
metal part and a known good earth ground.
Measure the AC voltage across the resistor with the
AC voltmeter.
Move the resistor connection to eachexposed metal
part, particularly any exposed metal part having a
return path to the chassis, and meausre the AC
voltage across the resistor. Now, reverse the plug in
the AC outlet and repeat each measurement. voltage
measured Any must not exceed 0.75 V AC (r.m.s.).
This corresponds to 0.5 mA AC (r.m.s.).
Warning
1. This equipment has been designed and manufactured to meet international safety standards.
2. It is the legal responsibility of the repairer to ensure that these safety standards are maintained.
3. Repairs must be made in accordance with the relevant safety standards.
4. It is essential that safety critical components are replaced by approved parts.
5. If mains voltage selector is provided, check setting for local voltage.
Good earth ground
Place this
probe on
each exposed
metal part.
AC VOLTMETER
(Having 1000
ohms/volts,
or more sensitivity)
1500
10W
0.15 F AC TYPE
HA-W500RF (EG)/(EK)
(No.70270) 3
R
L
R
3
1
7
8
6
5
2
12
10
1
4
9
4
11
4
4
14
13
15
R
1.Disassembly
Receiver(Headphones)
Transmitter
In case of some problems arise in this transmitter unit,
have to change the transmitter unit itself, due to avoid
the law of radio regulation.
1.Remove the ear pad 1 from the driver unit ass'y (L) 2 and (R) 3.
2.Remove the screw 4 and pull up the driver unit ass'y (L) 2 and (R) 3.
3.At channel L. Remove the screw 5 and insulation washer 6, and pull up the charge print circuit board 7.
4.Remove the switch knob 8.
5.Remove the screw 9 and remove the battery door 10 from the housing ass'y (L) 12.
6.Remove the battery 11 from the housing ass'y (L) 12.
7.At channel R. Remove the main print circuit board 13 from the housing (R) 14
8.Remove the wire with solder from the charge and main print circuit board 7 13, then remove the headband
ass'y 15.
HA-W500RF (EG)/(EK)
4 (No.70270)
Notes:
1. The thick line (
) is the B (+) power supply.
2. This circuit diagram is the r eference diagram. Cir cuits and constans ar e subject to change without notice for
improvement.
3. Values printed in red show the voltares of each section measur ed by the tester (inter nal resistance 20 kOhms/V),
with the power switch ON.
4. Parts marked with
(in the shaded area
) are safety parts.When replacing these, be sure to use only the
designated parts to ensure safety.
Use of Circuit Diagram
*
N750
Test-1
High RF in
Test-3
Low RF in
Test-8
VCC
Test-7
GND
Test-5
R out
Test-6
L out
VR3 795.1Mhz
VR4 791.5Mhz
OFF
ON
JX1
CHARGE OUTPUT
TERMINAL
Rout
Lout
Test-9
STEREO
2
16
28
11
6
23
3
30
20
5
17
1
21
4
15
29
18
25
IC2
CXA1538M
10
27
26
8
13
9
72
2
Rout
Lout
(C74)
Test-10
VT
TEST-11
REF V
X3
10.7M
C47
100
0p
+
C72
4U7
1k5
R13
D4
4148
C8
100 p
D2B GREEN
C40
1u
R12
330
C49
7p
C41
1u
+
C254U7
+
C43
220 u
C42
0.1u
+
-
IC4B
5
6
7
8
4
C73
0.1u
L3
12nH
R37300
C45
0.1u
+
C27
1U
TC1
1.5-3p
VR4
5k
1k
R25
1k
R26
C48
100
0p
R40
1M
D3 4148
Q6 8550
Q7
3904
R41
75k
Q8
3904
+ C38
100u
27k
R22
27k
R23
C22
12p
C75
0.01u
2k7
R19
VR2
100k
+
-
IC4A
LM393 or
NJM2903M
LM393 or
NJM2903M
3
2
1
8
4
2k7
R20
S1a SW SPDT
R42
50K
S1b
SW SPDT
+
C73
220u
R14
100K
+
C32
220u
VR1b
100k
VR1a
100k
C76
100p
L9
15nH
+
C36
2U2
+
C37
2U2
T2
R31
2K2
+ C44
10u
C77
1p
C78
1p
C83
10p
L1
15nH
C881000p
+
C28
4U7
+
C26
1U
+
C29
33U
+
C31
10U
IC1 7201-15
3
1
2
VI
VO
GND
Q9
5508
R56
0
Q1
5094
R49
27K
+ C32
0.47u
R50
330
R53
27K
C30
0.01U
C81
0.01U
Q11
5508
R54
330
+
C23
10U
C24
0.1U
+
C54
2u2
+
C55
2u2
IC5
78L06
3
1
2
VI
VO
GND
R34
2k2
+
C33
4U7
C10
10p
C59
10u
1K
R24
C61
10u
C60
47u
SPK1
32ohm
SPK2
32ohm
C84
0.01u
R30
1k
C17
3P*
C20
2P(N)
R47 18k
ANT1
1
VR5
5K
R33
2K2
R32
3K3
C39
1000p
IC3
LM4809
2
7
1
3
5
4
6
8
IN1
OUT2
OUT1
BY PASS
MUTE
GND
IN2
VCC
VR3
5k
R35
100k
R36
100k
R38
100k
R434k7
R39
68k
C19
0.001u
R4410k
1k
R27
R4510k
1k
R28
C1
3p*
C3
5p6
L8
0.33uh
C53
56P
X1
C2
3P*
R2
39k
R4
470
100
R29
C5
1u
R1
18k
D1
V809
C46
0.1u
R11
100
T1
C874p
X2
10.7MHz
R15
3k3
R16
3k3
C34
0.015u
C35
0.015u
D2A RED
C51
22P
C52
0.01u
10
R18
C21
12p
100K
R21
R46 82K
X4
863 MHz
L2
15nH
C80
0.01u
BATTERY
2.4V
Test-3
Test-1
Test-8
Test-9
Test-5
Test-6
Test-7
Test-10
Test-11
!
!
!
!
!
2.Schematic diagram
+
-
HA-W500RF (EG)/(EK)
(No.70270) 5
4.Print Circuit Board
Back side
Receiver (Headphones)
CHARGE P. C. BOARD
TOP
3.Measurement Condition
AC IN
Transmitter
Receiver (Headphones)
Distance : 1m (3.28ft)
Reference input signal
:1kHz 300mVp-p sine wave
Hedaphone volume control
: MAX
Surface
shows the B(+) power supply
shows the ground
shows others.