Parker TS2192, Руководство по обслуживанию

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1. Safety instruction
Before servicing and aligning this equipment, please read the following “X-RAY RADIATION
PRECAUTION” , “SAFETY PRECAUTION” and “PRODUCT SAFETY NOTICE” .
1.1 X-ray radiation protection
1.1.1 Too high voltage will produce radiation harmful to human health. To avoid such risk, the high
voltage should be regulated within the limited value. The normal value of the high voltage of this
receiver is 26.5kV at 0.9mA.
Under any circumstances, the high voltage should not exceed 30kV. When the TV set needs to be
fixed, please follow the inspection procedures of high voltage in item 4.6.1 under this
instruction ”Inspection of high voltage”. It is suggested that the value of high voltage be recorded
as part of maintenance work. It is most essential at the same time to use precise and dependable
high voltage meter.
1.1.2 This set is equipped with X-ray over radiation (FS) protection circuit to prevent over radiation of
X-ray in the case of abnormal increase of B+ voltage in the set or the reverse capacitor is open
circuit. Whenever fixing the set, FS circuit must be checked according to the inspection
procedures as in item 4.6.2 of this instruction, ”X-ray radiation protection test” to make sure the
circuit functions well.
1.1.3 The only source of TV set producing X-ray is CRT. To avoid X-ray radiation during the whole
process, the exact same type of CRT designated in the detail list must be replaced, when there is
a need to change CRT.
1.1.4 Some parts in this receiver have special safety-related characteristics for X-RAY RADIATION
protection. Please read the “Points of attention for products safety” before changing the
components, for the sake of safety.
1.2 Safety measures
1.2.1 When the TV set is working, the high voltage will be as high as approximately 30kV. When
adjusting the set after removing the cover or opening the back cabinet there will be risk of electric
shock, so
a) Before detaching the anode cap, please discharge it several times by grounding the anode of
CRT to earth many times to avoid electric shock.
b) Before moving the CRT, its anode must be thoroughly discharged. The CRT is a high vacuum
part. Once broken, its fragments will fly out violently. Therefore it must be very careful in
dismantling and loading it.
1.2.2 There are a lot of electronic and mechanical components in PCB that have safety related
Note: This service manual is only for professional service personnel’s reference. Before
servicing the unit, please read the following items carefully.