Jvc RVB 90 GY Service Manual

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HV-BQOGY
RV-BSOAG

-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 manufacturers
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. Fleplacement 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 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 pans 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.

0 Plug the AC line cord directly into the AC outlet. Using a Leakage Current Tested, measure
the leakage current from each exposed metal parts of the cabinet,particularly any exposed
metal part having areturn 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 1.5005? 10W resistor paralleled by
a 0.15uF AC-type capacitor between an exposed

metal part and a known good earth ground. E 83225?ng
Measure the AC voltage across the resistor with the ohms/volts,

AC voltmeter. or more sensitivity)
Move the resistor connection to eachexposed metal

part, particularly any exposed metal part having a 015;: AC TYPE

return path to the chassis, and meausre the AC __. Place this
voltage across the resistor. Now, reverse the plug in : l L, probe on

the AC outlet and repeat each measurement. voltage 4 V each exposed
measured Any must not exceed 0.75 V AC (r.m.s.). 150052 10W metal part.

This corresponds to 0.5 mA AC (r.m.s.).
Good earth ground

t-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.lt is essential that safety critical components are replaced by approved pans.

5.lf mains voltage selector is provided, check setting for local voltage.

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.

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RV-BSOGY
RV-BQOAG

3. Functions
Pin NO- Symbol |/0 Functions and operations
1 PD l APC amp input terminal
2 LD 0 APC amp output terminal
3 LD ON . | AFC ON/OFF control terminal
4 LDP -- Connect to ground
5 VCC -~ Power supply
6 RF- l inverse input pin for RF amp
7 RF OUT 0 FiFamp output
8 RF IN I RF input
9 CAGC l/O Connecting pin of AGC loop filter
10 ARF 0 RF output
11 CtENV I/O A capacitor is connected to this terminal to detect the envelope of RF signal
12 C.EA IIO A capacitor is connected to this terminal to detect the envelope of RF signal
13 CS BDO l/O A capacitor is connected to detect the lower envelope of RF signal
14 BD0 0 BBC output pin
15 CS BRT V0 A capacitor is connected to detect the lower envelope of RF signal
16 OFI'R O Of-track status signal output
17 INFtFDET 0 RF detection signal output
18 GND -- Ground
19 ENV O Envelope output
20 VFtEF 0 Reference voltage output
21 LB OFF -- Connect to ground
22 VDET O Vibration detection signal output
23 TE BPF I Input pin of tracking error through BPF
24 CROSS 0 Tracking error cross output
25 TE OUT 0 Tracking error signal output
26 TE- l Inverse input pin for tracking error amp
27 FE OUT 0 Output pin of focus error
28 FE- | inverse input pin for focus error amp
29 FBAL l Focus balance control
30 TBAL 1 Tracking balance control
31 PDFR I/O F lvV amp gain control
32 PDER I/O E l-V amp gain control
33 PDF l I-V amp input
34 PDE I l-V amp input
85 PD SD | l-V amp input
36 PD AC l |~V amp input

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RV-BQOGY
RV-BQOAG

lElectrical Characteristics of Tuner

Items Measurement Standard Adjusting
conditions Measurement method values posmons
Adjustment 0 - Band selection to : AM 1.Fieceive 522kHz(preset memory P1)from SSG Maximum
AM RF - Input position: through the standard loop antenna. output
tracking Standard loop antenna 2.Fleceive 1.629kHz(preset memory P2)irom SSG
throught the standard loop antena.Adjust L4 so that
the output at this time becomes maximum output L4
3.In case the voltage at the test point TP9 exceeds
5.0V,adjust L4 so that the voltage become 5.0V
:0,1V. In case the voltage is 5.0V or less,be sure
not to perform any adjustment.
4.Fleceive 603kHz(preset memory P3)trom SSG
through the standard loop, antena. Adjust L3 so L3
that the output at this time become maximumum.
5Fleceive 1,404kHz (preset memory P4)from SSG
through the standard loop antena. Adjust T02 so
that output at this becomes maximum.
6.Flepeat Steps (9 and (53 so that the output T02
becomes maximum.
Frequency Range
Effggncy Frequency Area Eraelggueency Frequency Area
MW/AM 522 ~ 1629 kHz B/E/EN/EE FM 65 ~ 74 MHz EE
MW/AM 530 ~ 1710 kHz J/C LW 144 ~ 288 MHz B/E/EN
MW/AM 531 ~ 1602 kHz A/U/UT/UP/US/UB/UX SW 2.3 ~ 21. 85 MHz A/U/UT/UP/US/UB/UX
FM 87.5 ~ 108 MHz B/E/EN SW 5.75~l7. 95 MHz A/U/UT/UP/US/UB/UX
The Marks for Designated Areas
J ..... the USA A .. . Australia C ..... Canada B ..... the UK
E Continental Europe EN Scandinavia EE Eastern Europe U Universal
UT Taiwan UP ..... Korea US ..... Singapore UB Hong Kong

UX Saudi Arabia

Please receive and check the broadcasting station near each frequency

when

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there is no SSG.