Sony HCD-GTK1i, Service Manual

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HCD-GTK1i/GTK2i
3
NOTES ON CHIP COMPONENT REPLACEMENT
• Never reuse a disconnected chip component.
• Notice that the minus side of a 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.
SAFETY CHECK-OUT (US MODEL)
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 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 0.75 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)
1.5 k Ω 0.15 μ F
AC
voltmeter
(0.75 V)
To Exposed Metal
Parts on Set
Earth Ground
Fig. A. Using an AC voltmeter to check AC leakage.
1. SERVICING NOTES
................................................ 4
2. DISASSEMBLY
2-1. Top Panel Block and Back Panel .................................... 6
2-2. Power SW Board, Trans Board and DC Fan................... 6
2-3. Main
Board ..................................................................... 7
2-4. VOL Board, LCD Board and IPOD Board ..................... 7
2-5. Front Panel ...................................................................... 8
2-6. Loudspeaker .................................................................... 8
3. TEST MODE
............................................................ 9
4. ELECTRICAL ADJUSTMENTS
........................ 11
5. DIAGRAMS
5-1. Block Diagram –Display and Power Section– ............... 13
5-2. Block Diagram –Main Section– ..................................... 14
5-3. Printed Wiring Boards –VOL, LCD and IPOD Board– . 16
5-4. Schematic Diagram –VOL and LCD Board– ................. 17
5-5. Schematic Diagram –IPOD Board– ................................ 18
5-6. Printed Wiring Boards –MAIN, SPK LED LEFT and SPK
LED RIGHT Board– ....................................................... 19
5-7. Schematic Diagram –MAIN Board (1/3)– ...................... 20
5-8. Schematic Diagram –MAIN (2/3), SPK LED LEFT and
SPK LED RIGHT Board– .............................................. 21
5-9. Schematic Diagram –MAIN Board (3/3)– ...................... 22
5-10. Printed Wiring Boards –TRANS and
POWER SW Board– ....................................................... 23
5-11. Schematic Diagram –TRANS and
POWER SW Board– ....................................................... 24
6. EXPLODED VIEWS
6-1. Back Panel Section ......................................................... 29
6-2. Top Panel Section ........................................................... 30
6-3. Front Panel Section ......................................................... 31
7. ELECTRICAL PARTS LIST
.............................. 32
TABLE OF CONTENTS