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§ SAFETY INSTRUCTIONS
§ SAFETY PRECAUTION
WARNING: Service should not be attempted by anyone unfamiliar
with the necessary precaution on this receiver.
The following are the necessary precaution to be observed before
servicing.
1.Always discharge the picture tube anode to the CRT conductive
coating the picture tube. the picture tube is hightly evacuated
and if broken, glass fragments will be violently expelled. Use
shatterproofgoggles and keep picture tube away from the body
while handling.
2.When replacing chassis in the cabinet,always be certain that all
the protective devices are put back in place, such as;
nonmetallic control knobs, insulating covers, shields, isolation
resistor-capacitor network, etc
3.Before retuning 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.
§ PRODUCT SAFETY NOTICE
Many electrical and mechanical parts in this chassis have special
safety-related characteristics. These characterictics 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 volage, wattage,
etc.Replacement parts which have these special safety
characteristics are identified in this manual and its
§ SERVICE NOTES
1.When replacing parts or circuit boards, clamp the lead wires to
terminal before soldering.
2.When replacing a high wattage resistor(metal oxide film
resistor)in the circuit board keep the resistor min 1/2 inch away
from the circuit board.
Plug the AC line cord directly into a AC outlet. Use an AC
voltmeter having 500 ohms per volt or more sensitivily 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 immediately.
AC VOLT METER
Good earth ground,
such as the water
pipe, conduit, etc.
supplements;electrical components having such features are
identified by shading 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 or other hazards.
3.Keep wires away form high voltage or high temperature
components.
3
0.15MFD
Place this probe
1500
OHM
10WATT
on each exposed
metallic part.
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