Jvc R X220L Service Manual

Page 1

SERVICEMANUAL

R-X220/R-X2208
R-X220L/R-X220LB

DEL

R-XZZO
Version
Model
R-XZZOL Feature Color
R-X22O - Silver
R-X220L with LW Silver
R-XZZOB - Black
R-X220LB with LW Black
Contents
Safety Precautions ........................ 1-1 5. Block Diagram .................... ' ..... 1-9
1. Specifications ......................... 1-2 Parts List .............. Separate-volume Insertion
2. Names of Controls and Their Functions ........ 1-3 6. R-X220/R-X220L Schematic Diagram
3. Removal Procedures ..................... 1-5 6-(1) RX220 Tuner Section. ............... 1-10
3-(1) Metal cover section .................. 1-6 6-(2) R-X220L Tuner Section .............. 1-11
3-(2) Front panel section .................. 1-6 6-(3) R-X220/R-X220L Amplifier Section ..... 1-12
3-(3) Chasis base section .................. 1-6 6-(4) Internal Block Diagram of
4. FM/AMlMW/LW) Tuner Alignment Procedures . . . 1~7 Major LSI le .................... 113
N0. 2814

This manual combines two single volumes; Service manual and Parts list.

Feb.1985

Page 2

Safety Precautions

1. The design of this product contains special hardware,

many circuits and components specially for safety pur-
poses.

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. Service should be
performed by qualified personnel only.

. Alterations of the design 'or circuitry of the product
should not be made. Any design alterations or additions
will void the manufacturers warranty and will further
relieve the manufacturer of responsibility for personal
injury or property damage resulting therefrom.

. Many electrical and mechanical parts in the product
have special safety-related characteristics. These charac-
teristics 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 ( A l on the parts list in Service
manual. The use of a substitute replacement which does
not have the same safety characteristics as the recom-
mended replacement part shown in the parts list in
Service manual may create shock, fire, or other hazards. 7
. The leads in the products are routed and dressed with
ties, clamps, tubings, barriers and/or the like to be
separated from live parts, high temperature parts, mov-
ing 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 they should be confirmed
to be returned to normal, after re-assembling.

. To confirm the polarity of the power cord and AC out
let (Canada only).

When replacing the power cord or the AC outlet, make
sure that the power switch or the protection device {the
primary fuse etc.) is NOT connected to the ground
power side of the plug and AC outlet (wider blade of
plug or wider hole of the AC outlet).

6. Leakage current check

(Safety for electrical shock hazard)

After re-assembling the product, always perform an

isolation check on the exposed metal parts of the

Products (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.

0 Plug the AC line cord directly into the AC outlet.
Using a "Leakage Current Tester", measure the
leakage current from each exposed metal part 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
0.5 mA AC (r.m.s.).

0 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
1500 .Q 10 W resistor paralleled by a 0.15 pF 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 0.75 V AC (r.m.s.).
This corresponds to 0.5 mA AC (r.m.s.).

AC VOLTMETER

7 4 (Having 1000 ohms/volt,
or more sensitivity.)

-O O-
0.15pF AC TYPE
._.....I ,-
Place this probe
s MA, 1. > on each exposed
lSOOQ 10W

metal part.

Good Earth Ground

CHECKING YOUR LINE VOLTAGE (Except for U.S.A., Canada, Australia, U.K. and Continental Europe.)
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 on the rear panel.

CAUTION Before selecting the "Voltage selector switch" to proper voltage disconnect the power plug.

1-1 (No. 2814)

Page 7

3-(1)

Metal Cover Section

. Remove the screws securing the metal cover - two

screws from its two sides and three from its rear side.
Extract the metal cover while lifting its rear side.

Front Panel Section

. Demount the metal cover (refer to item 3-(1) above).
. Remove three screws 6, ® and .

Remove five screws 0 through (59 - namely, those
screws that jointly secure the front panel and the
chassis base through the panel bottom side.

Remove screw - the one that secures the front
panel through its lower side.

Fastener

3-(3) Chassis Base Section

1.
2.

Demount the metal cover (refer to item 3-(1) above).

Remove 16 screws ® through ® and 6) through
- those screws that secure the chassis base

through its bottom side.
Remove two screws and . securing the heat
sink.

.Remove two screws ® and ® securing the

tuner PC board.

Extract the plastic rivet securing the amplifier PC
board.

Remove two fasteners ® and securing the
amplifier PC board. (Push in the fasteners while
using radio-repair pliers or a similar tool to grip the
fastener head.)

Open the chassis base while loosening the stopper
engaged with the rear panel.

(No. 2814) 16