Chapter 1 General Adjustments; Safety Instructions - Toshiba 28Z33B Service Manual

CHAPTER 1 GENERAL ADJUSTMENTS
WARNING: BEFORE SERVICING THIS CHASSIS, READ THE "X-RAY RADIATION PRECAUTION", "SAFETY PRE-
CAUTION" AND "PRODUCT SAFETY NOTICE" INSTRUCTIONS BELOW.
1. Excessive high voltage can produce potentially hazard-
ous X-RAY RADIATION. To avoid such hazards, the high
voltage must not be above the specified limit. The nomi-
nal value of the high voltage of this receiver is (A) kV at
zero beam current (minimum brightness) under a (C) V
AC power source. The high voltage must not, under any
circumstances, exceed (B) kV.
Refer to table-1 for high voltage (A), (B) & AC voltage (C).
(See SETTING & ADJUSTING DATA on page 15)
Each time a receiver requires servicing, the high voltage
should be checked following the HIGH VOLTAGE CHECK
procedure in this manual. It is recommended that the
reading of the high voltage be recorded as a part of the
service record. It is important to use an accurate and
reliable high voltage meter.
WARNING : Service should not be attempted by anyone unfamiliar with the necessary precautions on this receiver. The
following are the necessary precautions to be observed before servicing this chassis.
1. An isolation transformer should be connected in the power line between the receiver and the AC line before any service
is performed on the receiver.
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 fragments 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.
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 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 the international hazard symbols on the schematic diagram and the parts list.
Before replacing any of these components, read the parts list in this manual carefully. The use of substitute
replacement parts which do not have the same safety characteristics as specified in the parts list may create shock,
fire, X-ray radiation or other hazards.

SAFETY INSTRUCTIONS

X-RAY RADIATION PRECAUTION
2. The only source of X-RAY RADIATION in this TV
receiver is the picture tube. For continued X-RAY RA-
DIATION protection, the replacement tube must be
exactly the same type tube as specified in the parts
list.
3. Some part in this receiver have special safety-related
characteristics for X-RAY RADIATION protection. For
continued safety, parts replacement should be under-
taken only after referring to the PRODUCT SAFETY
NOTICE below.
SAFETY PRECAUTION
PRODUCT SAFETY NOTICE
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