NEC DTE-29U1TH, Service Manual

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Service Manual CP-785F
2 - Safety instruction
WARNING : Only competent service personnel may carry out work involving the testing or repair
of this equipment.
X-RAY RADIATION PRECAUTION
1. Excessive high voltage can produce potentially hazardous X-RAY RADIATION. To avoid
such hazards, the high voltage must not exceed the specified limit. The nominal value of the
high voltage of this receiver is 28~30 KV at max beam current. The high voltage must not
under any circumstances, exceed 32 KV. Each time a receiver requires servicing, the high
voltage should be checked. It is important to use an accurate and reliable high voltage meter.
2.The only 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 parts list.
SAFETY PRECAUTION
1. Potentials of high voltage are present when this receiver is operating. Operation of the
receiver outside the cabinet or with the back board removed involves a shock hazard from the
receiver.
1) Servicing should not be attempted by anyone who is not thoroughly familiar with the
precautions necessary when working on high voltage equipment.
2) Discharge the high potential of the picture tube before handling the tube. The picture tube is
highly evacuated and if broken, glass fragments will be violently expelled.
2. If any Fuse in this TV receiver is blown, replace it with the FUSE specified in the
Replacement Parts List.
3. When replacing a high wattage resistor (oxide metal film resistor) in circuit board, keep the
resistor 10 mm away from circuit board.
4. Keep wires away from high voltage or high temperature components.
5. This receiver must operate under AC 240 volts, 5O Hz. NEVER connect to DC supply or any
other power or frequency.
PRODUCT SAFETY NOTICE
Many electrical and mechanical parts in this equipment 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 higher voltage, wattage, etc. Replacement parts which have
these special safety characteristics are identified in this manual and its supplements, electrical
components having such features are identified by designated symbol on the parts list. Before
replacing any of these components, read the parts list in this manual carefully. The use of
substitutes replacement parts which do not have the same safety characteristics as specified in
the parts list may create X-ray Radiation.