BDP-N460 - Sony DVD Service Manual (repair manual). Page 2

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 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” indication 
is 0.75V, 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 2V AC range are suitable. (See 
Fig. A)

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

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 transistors, 

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 recommend 
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:

Ω

μ

Unleaded solder
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.

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

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

This label is located on the laser
protective housing inside the 
enclosure.