TOSHIBA 20A43
Service Manual

SERVICING NOTICES ON CHECKING
1. KEEP THE NOTICES
As for the places which need special attentions, they are indicated with the labels or seals on the cabinet, chassis and parts. Make sure to keep the indications and notices in the operation manual.

6. AVOID AN X-RAY
Safety is secured against an X-ray by considering about the cathode-ray tube and the high voltage peripheral circuit, etc. Therefore, when repairing the high voltage peripheral circuit, use the designated parts and make sure not modify the circuit. Repairing except indicates causes rising of high voltage, and it emits an X-ray from the cathoderay tube.

2. AVOID AN ELECTRIC SHOCK
There is a high voltage part inside. Avoid an electric shock while the electric current is flowing.

3. USE THE DESIGNATED PARTS
The parts in this equipment have the specific characters of incombustibility and withstand voltage for safety. Therefore, the part which is replaced should be used the part which has the same character. Especially as to the important parts for safety which is indicated in the circuit diagram or the table of parts as a mark, the designated parts must be used.

7. PERFORM A SAFETY CHECK AFTER SERVICING
Confirm that the screws, parts and wiring which were removed in order to service are put in the original positions, or whether there are the portions which are deteriorated around the serviced places serviced or not. Check the insulation between the antenna terminal or external metal and the AC cord plug blades. And be sure the safety of that.
(INSULATION CHECK PROCEDURE)

4. PUT PARTS AND WIRES IN THE ORIGINAL POSITION AFTER ASSEMBLING OR WIRING
There are parts which use the insulation material such as a tube or tape for safety, or which are assembled in the condition that these do not contact with the printed board. The inside wiring is designed not to get closer to the pyrogenic parts and high voltage parts. Therefore, put these parts in the original positions.

1. Unplug the plug from the AC outlet. 2. Remove the antenna terminal on TV and turn on the TV. 3. Insulation resistance between the cord plug terminals and the eternal exposure metal [Note 2] should be more than 1M ohm by using the 500V insulation resistance meter [Note 1]. 4. If the insulation resistance is less than 1M ohm, the inspection repair should be required.
[Note 1]

5. TAKE CARE TO DEAL WITH THE CATHODE-RAY TUBE
In the condition that an explosion-proof cathoderay tube is set in this equipment, safety is secured against implosion. However, when removing it or serving from backward, it is dangerous to give a shock. Take enough care to deal with it.

If you have not the 500V insulation resistance meter, use a Tester.
[Note 2]

External exposure metal: Antenna terminal Earphone jack

HOW TO ORDER PARTS
Please include the following informations when you order parts. (Particularly the VERSION LETTER.) 1. MODEL NUMBER and VERSION LETTER The MODEL NUMBER can be found on the back of each product and the VERSION LETTER can be found at the end of the SERIAL NUMBER. 2. PART NO. and DESCRIPTION You can find it in your SERVICE MANUAL.

IMPORTANT
Inferior silicon grease can damage IC's and transistors. When replacing an IC's or transistors, use only specified silicon grease (YG6260M). Remove all old silicon before applying new silicon.

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