akira CT-21AZ9, Service Manual

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Model No: CT-21AZ9A_21AZ9CP_21AZ9CP(SKD)_21AZ9R_21AZ9R(SKD)
Version 1.0
5
CAUTION
Before serving the chassis, read the “X-Ray Radiation Precaution”, “Safety Precaution” and
“Product Safety Notice” on this page.
X-RAY RADIATION PRECAUTION
1. Excessive high voltage can produce potentially hazardous X-Ray Radiation. To avoid such
hazards, the high voltage must not be above the specified limit. The normal value of the high
voltage of this receiver is 24KV at zero beam current (minimum brightness) under 220V AC
power source. The high voltage must not, under any circumstances, exceed 30KV.
2. Each time a receiver requires servicing, the high voltage should be checked following the High
Voltage Check procedure in this manual. It is recommended the reading of the high voltage
should be recorded as a part of the service record. It is important to use an accurate and reliable
high voltage meter.
3. The primary source of X-Ray Radiation in this TV receiver is the picture tube. For continued X-
Ray Radiation protection, the replacement tube must be exactly the same type tube as specified
in the part list.
4. Some parts in this receiver have special safety – related characteristics for X-Ray Radiation
protection. For continued safety, parts replacement should be undertaken only after referring to
the Product Safety Notice.
SAFETY PRECAUTION
Warning: Service should not be attempted by anyone unfamiliar with necessary precaution on this
receiver. The following are the necessary precautions observed before servicing this chassis.
1. Since the power supply circuit of this receiver is directly connected to the AC power line, an
isolation transformer should be used during any dynamic service to avoid possible shock hazard.
2. Always discharge the picture tube anode to the CRT conductive coating before handling the
picture tube. The picture tube is highly evacuated and if broken, glass fragment will be violently
expelled. Use shatter proof goggles and keep picture tube away from the unprotected body while
handling.
3. When replacing a chassis in the cabinet, always be certain that all the protective devices are put
back in place, such as: non-metallic control knobs, insulating covers, shields, isolation resistor-
capacitor network etc.
4. When replacing parts or circuit boards, disconnect the power cord.
5. When replacing a high voltage resistor (Metal oxide film resistor) on circuit board, keep the
resistor 10mm (1/2in.)away from circuit board.
6. Connection wires must be kept away from components with high voltage or high temperature.
7. If any fuse in this TV receiver is blow, replace it with the FUSE specified in the chassis part list.
8. The receiver is designed to operate with 220V(50/60Hz) AC mains.
PRODUCT SAFETY NOTICE
Many electrical and mechanical parts in this chassis have special safety –related characteristics. These
characteristics are often passed unnoticed by a visual inspection and the X-Ray Radiation protection
afforded by them cannot necessarily be obtained by using replacement components rated for high
wattage, etc. Replaced parts which have these special safety characteristics are identified in this manual
and its supplements, electrical components having such features are shaded on the schematic diagram
and the part list.
Before replacing any of these components, read the part list in this manual carefully. The use of
substitute replacement parts, which do not have the same safety characteristics, as specified in the part
list may create shock, fire, and X-Ray Radiation or other hazards.