Dragon 32 - Service Information (RWEW/RA/0082a)

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DRAGON DATA LIMITED.

SERVICE INFORMATION

SOUND AND COLOUR FAULTS

A. No Picture or Sound

1. Check transformer.

2. Check power supply circuit board.

(a) Check PL10

(b) Test voltages

(c) Check diodes.

3. Check RESET button operation.

4. Check IC15 properly seated.

5. Replace IC15.

B. No Sound

1. Check TV channel timing.

2. Retune modulator.

3. Change IC20.

C. Faulty Colour

1. Adjust RV1 (and RV2 if fitted).

2. Alter value of C7.

3. To obtain full green screen or to cure 'rainbow effect', fit a 2-22 pf capacitor trimmer instead of C7.

4. If colour fault on 22" or 27" SONY sets, then fit 15K resistor across Pin 4 of IC9 to Pin 4 of IC10.

5. Change IC9.

6. Change IC16.

7. Change IC12.

D. Garbage on Screen

1. If RESET switch cures fault, then change IC17.

2. Change IC15.

3. Change IC17.

4. Change IC18.


RWEW/RA/0082a

18.4.83