Jvc LAX 1 B Service Manual

Page 1

Sammie

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Specifications .....
Opevation of Au'omaiic Mecnanism

2-H} Change cycie mechanism ,,,,,,,,,,,,,,,,,,
Tonearm lift and return mechanism
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7(3) Leadrout Adjustment ,,
544; Speed Adjustmam
6 Schematic Diagram

Parts List ..

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Page 2

L~AX1/L-AX1 B J

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 per
formed by qualified personnel only.

2. Alterations of the design or circuitry of the product

should not be made. Any design alterations or additions
will void the manufacturer's warranty and will further
relieve the manufacturer of responsibility for personal in
jury or property damage resulting therefrom.

3. Many electrical and mechanical parts in the product

have special safety«related characteristics, These
characteristics are often not evident from visual Inspec~
tion 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 r'ECOIr ,
mended replacement part shown in the parts list in Serv
vice manual may create shock, fire, or other hazards.

4, 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 elec-
tric 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.

5. Leakage current check

(Safety for electrical shock hazardl
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 f2 10 W resistor paralleled by a 015 F AC7
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
(HAVING 1000 fl/V.
OR MORE SENSITIVITY]

0.15 pF ACATYPE I
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1500 9 10 W PLACE THIS PROBE

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ON EACH EXPOSED

GOOD EARTH GROUND

METAL PART.
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

line voltage in your area, If it doesnt, be sure to adjust the voltage selector swrtch to the
proper setting before operating this equment, The voltage selector swttch lS located under»

neath the platter.

CAUTION: Before selecting the "Voltage selector SWltch" to proper voltage, disconnect the

power plug,

VOLTS

1-l (No. 2820i

Page 9

L~AX1lL-AX1B

PARTS LIST

Contents

Main parts Location ..................................................... 2-2
Exploded View and Part Numbers , 2-3
Mechanism Base Ass'y . 2-3
. Tonearm Ass'y .............. . 2-3
' Mechanism Ass'y ..................... . 2-4
Printed Circuit Board Ass'y and Pans List .. , 2-6
' ENL-035fl Power Supply P.C. Board Ass'y . 2-6
Packing Materials and Pan List . .. 75'
Accessories List .....................

(Nov 2820) 2 i