Jvc PCX 104 BK Service Manual

Page 1

PC~X104BK C J

JVD
SERVICE MANUAL

PC-X104BK C/J

Contents

I Safety precautions ..............................
I Safely precaution about PC-X104 ..
I Instructions ..................
IE Location of main parts.
El Removal of main parts
E] Main adjustment ..
El Traublashooting ..
El VWreing Connections
[E] Block diagram
I Integrated circuit.
I Signal diagram...
Ii] Standard schematic diagram
I Tuner circuit ........................
I Cassette amplifier circuit
I CD amplifier cirwit .............

613%"?

DIGITAL AUDIO

I Power amplifier circuit
I S/etam control circuit
Location of P. C. board and parts List
I Main board.
I Tuner board
I CD amplifier board .....
Exploded view of enclosure assembly
I Speaker section .....
I Enclosure section M
I Enclosure section M2
Exploded view of mechanism assembly
I Cassette mechanism .

I CD mechmism ..
[E] Packing ......................

No. 10021

February 1997

Page 2

P 1043K 0/.)
I Safety Precautions

i. The design 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 pans
must beidentical to those used in the original circuits. Service 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 manufactures warranty and will further relieve the manufacture of responsibile
for personal injury or property damage resulting therefrom.

3. Many electrical and mechanical parts in the product have special safety 7 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 shadinglfiffl) and ( A)
on the schematic diagram and parts list in the service manual. The use of a substitute replacement which does not have the same
safety characteristics as the recommended replacement part shown in the parts list of seNioe 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, mpving parts and or sharp edges for the prevention of electric shock and fire hazard. When sennce is
required. the original lead routing and dress should be observed. and it should be confirmed that they have been returned to
normal. after reassembling.

5. Leakage current 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

AC VOLTMETER
transformerduring this check. m (Having 1000 ohms/volt,
- Plug the Ac line cord directly into the AC outlet. using aLeakage of mo" "hymn

current tester. measure the leakage current from each exposed 3-3-
0.15 uF AC TYPE

metal part of the cabinet, particulary any exposed metal pan

having a return path to the chassis. to a known good earth ground. pm; all; probe
on each exposed
Any leakage current must not exposeed 0.5mA AC(r.m.s.) 1500 n w W maul mm

' Alternate check method
Plug the AC line cord directly into the Ac outlet. Use an Ac 6° "h ""d

voltmeter having 1.000 ohms per volt or more sensitivity in the following manner. Connect a 1.500 ohms 10W resistor paralleled
by a 0.15 [1 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 each exposed metal part. particularly any exposed
metal part having a return path to the chassis. and measure the AC voltage across the resistor. Now. reverse the plug in the AC
outlet and repeat each measurement. Any voltage measured must not exceed 0.75V AC(r.m.s.).This corresponds to 0.5mA
AC(r.m.s.).

The lightning flash with arrowhead synbol, within an
equilateral triangle. is intended io alert the user to the
presence of uninsulaied 'dangorous voltage within the
products most-'9 that my be of sufficient nugnitude
to constitute a risk of electric shout to persons.

CAUTION. TO REDUCE THE RISK OF ELECTRIC SHOCK. _ _ > _ _ _
00 NOT REMOVE coven ion SACK). The exclamation W"! mum an Numeral W is
NO USER-SERVICEABLE PARTS INSIDE. WW to alert the user to the preserm oi IW
REFER SERVICING TO QUALIFIED SERVICE PERSONNEL. Wall"? and Wm (semang) Instructions In
the literature accompanying the appliance.

A CAUTION

Burrs formed during molding may be left over on some parts of the chassis. Therefore, pay attention to
such burrs In the case of preforming repair of this system.