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KE-MX42K1 (K)     3

After correcting the original service problem, perform the
following safety checks before releasing the set to the customer:
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. Check that all control knobs, shields, covers, ground straps,

and mounting hardware have been replaced. Be absolutely cer-
tain that you have replaced all the insulators.

4. 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.

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

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

6. Check the line cords for cracks and abrasion. Recommend the

replacement of any such line cord to the customer.

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

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

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” 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 VOMs that are suitable. Nearly all battery
operated digital multimeters that have a 2 V AC range are suit-
able.  (See Fig. A)

Fig. A. Using an AC voltmeter to check AC leakage.

Ω

µF

!

KE-MX42K1 (K)     4

1-1.

REAR COVER REMOVAL .............................. 1-1

1-2.

UD BOARD REMOVAL .................................. 1-2

1-3.

A1 AND J2 BOARDS REMOVAL ................... 1-2

1-4.

DE2, DIC2, J1 AND MS2A BOARDS

REMOVAL ........................................................ 1-3

1-5.

F AND K BOARDS REMOVAL ...................... 1-3

1-6.

H2 BOARD REMOVAL ................................... 1-4

1-7.

HM AND H1 BOARDS REMOVAL ................ 1-4

1-8.

SPEAKER BOX REMOVAL ............................ 1-5

1-9.

SWITCHING REGULATOR REMOVAL ....... 1-5

1-10. SHIELD ASSY REMOVAL .............................. 1-6

1-11. PLASMA DISPLAY PANEL REMOVAL ....... 1-6

1-12. H3 AND H4 BOARDS REMOVAL ................. 1-7

2-1.

White Balance Adjustment ................................ 2-1

3-1.

BLOCK DIAGRAMS ........................................ 3-1

(1)

AE BOARD ................................................... 3-1

(2)

DE2(1/2) AND J2 BOARDS ......................... 3-2

(3)

DE2(2/2) BOARD ......................................... 3-3

(4)

J1 BOARD ..................................................... 3-4

(5)

DIC2 BLOCK ................................................ 3-5

(6)

H1, H2, H3, H4 AND K BOARDS ............... 3-6

(7)

HM AND UD BOARDS ............................... 3-7

3-2.

FRAME DIAGRAMS ........................................ 3-8

3-3.

CIRCUIT BOARDS LOCATION ..................... 3-9

3-4.

SCHEMATIC  DIAGRAMS  AND

PRINTED  WIRING  BOARDS ........................ 3-9

(1)

Schematic Diagrams of A1 Board ................. 3-10

(2)

Schematic Diagrams of DE2 Board .............. 3-14

(3)

Schematic Diagrams of DIC2 Board ............. 3-20

(4)

Schematic Diagram of H1 and H2 Boards .... 3-26

(5)

Schematic Diagram of H3 and H4 Boards .... 3-27

(6)

Schematic Diagram of HM and J2 Boards .... 3-28

(7)

Schematic Diagram of J1 Board .................... 3-29

(8)

Schematic Diagram of K Board .................... 3-30

(9)

Schematic Diagram of UD Board .................. 3-31

3-5.

SEMICONDUCTORS ....................................... 3-32

4-1.

COVER AND STAND ...................................... 4-2

4-2.

SPEAKER .......................................................... 4-3

4-3.

CHASSIA-1 ........................................................ 4-4

4-4.

CHASSIA-2 ........................................................ 4-5

4-5.

PACKING MATERIALS .................................. 4-6

KE-MX42K1 (K)

1-1

5

 Six screws

    (+BVTP 4x16)

5

 Four screws

    (+BVTP 4x16)

5

 Four screws

    (+BVTP 4x16)

6

 Six screws

    (+PSW 3x6)

6

 Two screws

    (+PSW 3x6)

2

 Stand Assy

4

 Speaker cover (R) Assy

7

 Six screws

    (+PSW 4x10)

1

 Two screws

    (+PSW 5x25) (Stand)

1

 Two screws

    (+PSW 5x25) (Stand)

3

 Speaker cover (L) Assy

8

 Three screws

    (+PSW 5x10)

8

 Three screws

    (+PSW 5x10)

6

 Four screws

    (+PSW 3x6)

6

 Four screws

    (+PSW 3x6)

9

 Rear cover

KE-MX42K1 (K)

1-2

3

 A Shield (Top) Assy

7

 PWB U bracket Assy

2

 Two screws

    (+PSW 3x6)

1

 Two revet nylon

4

 Screw

    (+PSW 4x8)

8

 Four screws

    (+PSW 3x6)

9

 UD board

6

 Four screws

    (+BVTP 3x12)

5

 Two screws

    (HEX)

2

 DM Block Assy

1

 Four screws

    (+PSW 3x6)

3

 Four screws

    (+PSW 3x6)

4

 A1 board

5

 Two screws

    (+PSW 3x6)

6

 J2 board