Jvc RX 517 VTN Service Manual

Page 1

JVD

RX-516VBK

RX-517VTN A .....

Area Suffix

C ..... Canada
J ...... the U.S.A.
UT . . . Taiwan

Other Area

Contents

Safety Precautions ........................ 1-2
Instruction Book .......................... 1-3
Description of Major [Cs ................. 1-17
Internal Connection of Display ........... 1-22
Disasssembly Procedures ................. 1-23

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bmnr v I." In

I! Remote //II

Control Coupons!"
Adjustment Procedures ................... 1-24
Block Diagrams ......................... 1-26
Schematic Diagram ................. Insertion
Printed Circuit Boards ............... Insertion

Parts List

No. 20495
Jan. 1995

RX-516VBK
RX-517VTN

Page 2

RX-516VBK
RX-517VTN

Safety Precautions

l. The 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 (A) on the Parts
List in the Service Manual, The use of a substitute repalcement 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,
contorl 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 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.).

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 1.50052 10 W
resistor paralleled by a 0.15 pF AC-type capacitor between an exposed metal part and a
known good earth ground.
Ac VOLTMETER

Measure the AC voltage across the resistor .
with the AC voltmeter. E gang/gag
Move the resistor connection to each exposed o C 0' "09 SEMilVitY-l
metal part, particularly any exposed metal part
having a return path to the chassis, and 0.15pF Ac TYPE
meausre the AC voltage across the resistor. [-
Now, reverse the plug in the AC outlet and [:I '3: this
repeat each measurement. Any voltage - vvr ngzheefgosed
measured must not exceed 0.75VAC (r.m.s.). 150°91°W metal part.
This corresponds to 0.5 mA AC (r.m.s.). Good eanh ground

--Warmng

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.

. Repairs must be made in accordance with the relevant safety standards.
. It is essential that safety critical components are replaced by approved parts.
5. If mains voltage selector is provided, check setting for local voltage.

Aw

1-2 (No. 20495)

Page 18

RX- 5 1 (NB K
RX- 5 1 7VTN

I M50198P(|C602) : Digital Delay IC

1. Explanation of the operation

Audio signal is input to LPFI to reduce the high frequency components. The output from LPFl is coded to 1 bit signal by ADM
modulator and comparator with inside .

This digital signal is input to main control logic.

And this signal obtain various efl'ect,and is written in SRAM .

At the same time main control logic read the data from SRAM ,and input it to ADM demodulator .

The ADM demodulator converts lbit signal to analog signal.

The analog signal is inputto LPF2 to reduce the suprius components,and output to Pin 13.

LPFI Reject the high frequency components which is contained the input signal and unnecessary.
LPFZ Reject the suprius components which is generated by the ADM demodulation by using with comparator,
0P1,CCl For ADM modulator.
0P2,CCZ For ADM demodulator.
2. Terminal Layout 3,pin function
ovvuo E E A-VCC :1}: Symbol Function n; Symbol Function
X'" E E "N 1 ovoo Power Supply 13 LP our Output of LPF
xii: E g :2; 2 x IN Oscillation Terminal 14 LP IN Input of LPF
DE E 3 mm 3 X OUT Oscillation Terminal 15 OF OUT Integrator output
DEB E El REF 4 DEL1 Delay time control 16 OF IN Integrator input
DEM E E on 5 DELZ Delay time control 17 0C2 Current control
ll-COM/EASY E El Ga 6 DELa Delay time control 18 0C1 Current control
MUTE E E 0" 'N 7 DELA Delay time control 19 REF 1/2 Vcc
M023: E g :12 8 pCOM/ EASY Connected to GND 20 OP IN Integrator input
A-GND E E 0! 9 MUTE Connected to GND 21 OF OUT Integrator output
10 M.TIME Connected to GND 22 LP OUT Output of LPF
11 D-GND Analog GND 23 LP IN Input of LPF
12 A-GND Digital GND 24 A-VCC Power supply

4. Block Diagram

Iz_4l Eil Izzl ITII [2-0] II'EI Ifil ITa'l
.- - -.
I r ---------
I
I I
I I
I :
b : - o 4' :
I + 7 I
LP E on E LPFZ
} DICI PREDICT i
l « CIRCUIT CIRCUIT .
I I
L--__'_ _____ .l L _____ '_ _____
ADM MODULATOR ADM MODULATOR
Power . . A 8Kbit
on MaIn Control Loglc SRAM
Reset I 4
. Mutiny Time
Delay TIme Control Contra
|_l BI Iii LI LSJ Iii LZJ LI Ll Ml |_l Ill

1-18 (No. 20495)

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