CMT-EP505, HCD-EP505 - Sony Audio Service Manual (repair manual). Page 2

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• Never reuse a disconnected chip component.
• Notice that the minus side of a tantalum capacitor may be dam-

aged by heat.

• Keep the temperature of the soldering iron around 270 ˚C dur-

ing 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.

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.

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 0.75 V, 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 2 V AC range are suit-
able.  (See Fig. A)

CAUTION

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

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This appliance is classified as
a CLASS 1 LASER product.
The CLASS 1 LASER
PRODUCT MARKING is
located on the bottom.

Ω

µ

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