Sony hbd e 770 w service manual

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HBD-E770W

This appliance is classified as
a CLASS 1 LASER product.
This marking is located on the
rear or bottom exterior.

CLASS 1 LASER PRODUCT
LUOKAN 1 LASERLAITE

KLASS 1 LASERAPPARAT

NOTES ON CHIP COMPONENT REPLACEMENT

- Never reuse a disconnected chip component.

- Notice that the minus side ofa tantalum capacitor may be dam-
aged by heat.

FLEXIBLE CIRCUIT BOARD REPAIRING

- Keep the temperature of soldering iron around 270 °C during
repairing.

- Do not touch the soldering iron on the same conductor of the
circuit board (within 3 times).

- Be careful not to apply force on the conductor when soldering
or unsoldering.

CAUTION
Use of controls or adjustments or performance of procedures
other than those specified herein may result in hazardous radia-

tion exposure.

SAFETY-RELATED COMPONENT WARNING!

COMPONENTS IDENTIFIED BY MARK A OR DOTTED LINE
WITH MARK A ON THE SCHEMATIC DIAGRAMS AND IN
THE PARTS LIST ARE CRITICAL TO SAFE OPERATION.
REPLACE THESE COMPONENTS WITH SONY PARTS
WHOSE PART NUMBERS APPEAR AS SHOWN IN THIS
MANUAL OR IN SUPPLEMENTS PUBLISHED BY SONY.

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SAFETY CHECK-OUT

After correcting the original service problem, perform the follow-
ing safety check before releasing the set to the customer:

Check the antenna terminals, metal trim, metallized knobs)
screws. and all other exposed metal parts for AC leakage.

Check leakage as described below.

LEAKAGE TEST

The AC leakage from any exposed metal part to earth ground and

from all exposed metal parts to any exposed metal part having a

return to chassis, must not exceed 0.5 mA (500 microamperes.).

Leakage current can be measured by any one ofthree methods.

1. A commercial leakage tester. such as the Simpson 229 or RCA
WT-540A. Follow the manufacturers instructions to use these
instruments.

2. A battery-operated AC milliammeter. The Data Precision 245
digital multimeter is suitable for thisjob.

3. Measuring the voltage drop across a resistor by means of a
VOM or battery-operated AC voltmeter. The limit" indication
is 0.75 V, so analog meters must have an accurate low-voltage
scale. The Simpson 250 and Sanwa SH-63Trd are examples
of a passive VOM that is suitable. Nearly all battery operated
digital multimeters that have a 2 V AC range are suitable. (See
Fig. A)

To Exposed Metal
Parts on Set
AC
0.15 pF :: g 1.5 kn / voltmeter
(0. 75 V)

_T_ Earth Ground
Fig. A. Using an AC voltmeter to checkAC leakage.