HCD-GPX6/GPX7
SAFETY CHECK-OUTNotes on chip component replacement
After correcting the original service problem, perform the follow-? Never reuse a disconnected chip component.
ing safety check before releasing the set to the customer:? Notice that the minus side of a tantalum capacitor may be dam-
Check the antenna terminals, metal trim, Ometallized� knobs,aged by heat.
screws, and all other exposed metal parts for AC leakage.
Check leakage as described below.Flexible Circuit Board Repairing
? Keep the temperature of the soldering iron around 270 °C dur-
LEAKAGE TESTing repairing.
The AC leakage from any exposed metal part to earth ground and? Do not touch the soldering iron on the same conductor of the
from all exposed metal parts to any exposed metal part having acircuit board (within 3 times).
return to chassis, must not exceed 0.5 mA (500 microamperes.).? Be careful not to apply force on the conductor when soldering
Leakage current can be measured by any one of three methods.or unsoldering.
1. A commercial leakage tester, such as the Simpson 229 or RCA
WT-540A. Follow the manufacturersO instructions to use these
CAUTION
Use of controls or adjustments or performance of proceduresinstruments.
2. A battery-operated AC milliammeter. The Data Precision 245
other than those specified herein may result in hazardous ra-digital multimeter is suitable for this job.
diation exposure.
3. Measuring the voltage drop across a resistor by means of a
VOM or battery-operated AC voltmeter. The Olimit� 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-This appliance is classified as
a CLASS 1 LASER product.amples of a passive VOM that is suitable. Nearly all battery
The CLASS 1 LASER
PRODUCT MARKING isoperated digital multimeters that have a 2 V AC range are suit-
able. (See Fig. A)
located on the rear exterior.
To Exposed Metal
Parts on Set
AC
0.15 ?F1.5 k&voltmeter
(0.75 V)
Earth Ground
Fig. A. Using an AC voltmeter to check AC leakage.
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)
: LEAD FREE MARK
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
SAFETY-RELATED COMPONENT WARNING!!heated tip is applied for too long, so be careful!
COMPONENTS IDENTIFIED BY MARK 0 OR DOTTED? Strong viscosity
Unleaded solder is more viscou-s (sticky, less prone to flow)
LINE WITH MARK 0 ON THE SCHEMATIC DIAGRAMS
AND IN THE PARTS LIST ARE CRITICAL TO SAFEthan ordinary solder so use caution not to let solder bridges oc-
OPERATION. REPLACE THESE COMPONENTS WITHcur such as on IC pins, etc.
SONY PARTS WHOSE PART NUMBERS APPEAR AS? Usable with ordinary solder
SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUB-It is best to use only unleaded solder but unleaded solder may
LISHED BY SONY.also be added to ordinary solder.
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ACEC
SONY
