DVP-FX810, DVP-FX810BP (serv.man2) - Sony DVD Service Manual (repair manual). Page 2

CAUTION

Use of controls or adjustments or performance of procedures
other than those specified herein may result in hazardous ra-
diation exposure.

0

0

Ω

µ

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 of three 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 this job.

3. Measuring the voltage drop across a resistor by means of a

VOM or battery-operated AC voltmeter.  The “limit” indica-
tion is 0.75V, so analog meters must have an accurate low-
voltage scale.  The Simpson 250 and Sanwa SH-63Trd are ex-
amples of a passive VOM that is suitable.  Nearly all battery
operated digital multimeters that have a 2V AC range are suit-
able.  (See Fig. A)

1. Check the area of your repair for unsoldered or poorly-sol-

dered connections.  Check the entire board surface for solder
splashes and bridges.

2. Check the interboard wiring to ensure that no wires are

“pinched” or contact high-wattage resistors.

3. Look for unauthorized replacement parts, particularly transis-

tors, that were installed during a previous repair.  Point them
out to the customer and recommend their replacement.

4. Look for parts which, though functioning, show obvious signs

of deterioration.  Point them out to the customer and recom-
mend their replacement.

5. Check the line cord for cracks and abrasion. Recommend the

replacement of any such line cord to the customer.

6. Check the B+ voltage to see it is at the values specified.

7. Check the antenna terminals, metal trim, “metallized” knobs,

screws, and all other exposed metal parts for AC leakage.
Check leakage as described below.

After correcting the original service problem, perform the following
safety checks before releasing the set to the customer:

The use of optical instrument with this product will increase eye
hazard.

Boards requiring use of unleaded solder are printed with the lead-
free mark (LF) indicating the solder contains no lead.
(Caution: Some printed circuit boards may not come printed with
the lead free mark due to their particular size.)

Unleaded solder has the following characteristics.
• Unleaded solder melts at a temperature about 40

°

C higher than

ordinary solder.
Ordinary soldering irons can be used but the iron tip has to be
applied to the solder joint for a slightly longer time.
Soldering irons using a temperature regulator should be set to
about 350

°

C.

Caution: The printed pattern (copper foil) may peel away if the
heated tip is applied for too long, so be careful!

• Strong viscosity

Unleaded solder is more viscous (sticky, less prone to flow) than
ordinary solder so use caution not to let solder bridges occur
such as on IC pins, etc.

• Usable with ordinary solder

It is best to use only unleaded solder but unleaded solder may
also be added to ordinary solder.

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