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SAFTY PRECAUTIONS
WARNING: BEFORE SERVICING THIS CHASSIS, READ THE "X-RAY RADIATION PRECAUTION", "SAFETY PRECAU-
TION" AND "PRODUCT SAFETY NOTICE" INSTRUCTIONS BELOW.
X-RAY RADIATION PRECAUTION
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 nominal
value of the high voltage of this receiver is ® kV at zero
beam current (minimum brightness) under a © V AC power
source. The high voltage must not, under any circum-
stances, exceed ® kV.
ie
Each
er requires servicing, the high voltage
should be checked following the HIGH VOLTAGE CHECK
procedure in this manual, It is recommended that the read-
ing 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.
2. The only source of X-RAY RADIATION in this TV receiver
is the picture tube. For continued X-RAY RADIATION pro-
tection, 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 char-
acteristics for X-RAY RADIATION protection. For contin-
ued safety, parts replacement should be undertaken only
after referring to the PRODUCT SAFETY NOTICE below.
SAFETY PRECAUTION
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.
4. Before returning the set to the customer, always
perform
an AC
leakage
current
check
on
the
exposed
metallic
parts of the cabinet,
such
as
antennas, terminals, screwheads,
metal overlays,
control shafts etc. to be sure the set is safe to
operate without danger of electrical shock.
Plug
the AC line cord directly into a 220V AC outlet {do
not use a line isolation transformer during this
check).
Use an AC voltmeter having 5000 ohms
per volt or more sensitivity in the following manner:
Connect a 1500 ohm 10 watt resistor, paralleled by
a 0.15 mfd, AC type capacitor, between a known
good earth ground (water pipe, conduit, etc.) and
the exposed metallic parts, one at a time.
Measure
the AC voltage across the combination of 1500 ohm
resistor and 0.15 mfd capacitor.
Reverse the AC
plug at the AC outlet and repeat AC voltage
measurements for each exposed metallic part.
Voltage measured must not exceed 0.3 volts. RMS.
This corresponds to» 0.2 .milliamp.;-AC;
.Any: value
exceeding this. limit. constitutes a. potential. shock
hazard and must be corrected immediate!
a
AC VOLTMETER
0.45MFED
Place 'this probe on
Good earth ground
:},6ach exposed
such as a water'
"ES
A
ud
metallic part.
Pipe, conduit, ete.
4599 sans
ts
§
40 watt"
PRODUCT SAFETY NOTICE
Many electrical and mechanical paris 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 char-
acteristics 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.
No.51281
3
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