IMPORTANTSERVICE SAFETYINFORMATION
Operating the receiver outside of its cabinet or with its back removed involves ashock hazard. Work on these
models should onlybe performed bythose who are thoroughlyfamiliar with precautions necessarywhen working on
high voltage equipment.
Exercise care whenservicing this chassis with power applied. ManyBplus and high voltage RFterminals are
exposed which, if carelesslycontacted, can cause serious shock or result in damage to the chassis. Maintain
interconnecting ground lead connections between chassis, escutcheon, picture tube dag andtuner whenoperating
chassis.
These receivers havea polarized”AC line cord. The AC plug is designedto fit into standard AC outlets in one
direction only.The wide blade connects to the ground side”and the narrow blade connects to the hot side”of theAC
line. This assures that the TVreceiver is properlygrounded to the house wiring. Ifan extension cord must be used,make
sure it is of the polarized”type.
Since the chassis of this receiveis connectedto one sideof the AC supplyduring operation, service should not be
attempted byanyone not familiar with the precautions necessarywhen working on these types of equipment.
When it is necessaryto make measurements or tests with AC power applied to the receiver chassis, an Isolation
Transformer must be used as asafetyprecaution and to prevent possible damage to transistors. The Isolation
Transformer should be connected between the TVline cord plug and the AC power outlet.
Certain Highvoltage (HV) maybe cause X-rayradiation. Receivers should not be operated with HVlevels
exceeding thespecified rating for their chassis type. Higher voltage mayalso increase the possibilityof failure in the HV
supply.
Itis important to maintain specified values of all components in the horizontal and highvoltage circuits and
anywhere else in the receivethat could cause arise in highvoltage, or operating supplyvoltages. No changes should be
made the original design of the receiver.
Components shown in theshadedareas onthe schematic diagramand/or identified byin the replacement parts list
should be replaced onlywith exact factoryrecommended replacement parts. The use of unauthorized substitute parts
man creats maycreate shock, fire, X-rayradiation, or other hazards.
Todetermine the presence of high voltage, use anaccurate high impedance HVmeter connected between the
second anode leadand he CRTdag grounding device. When servicing the High Voltage Systemremovestatic charges
fromit byconnecting a10KOhmresistor in series Wan insulated wire(such as test probe) between thepicture tube dag
and 2nd anode lead(HaveAC line corddisconnected fromAC supply).
The picture tubeuse in this receiver employintegral implosion protection. Replace with atubeof the sametype
number for continued safety.Do not lift picture tube bythe neck. Handle the picture tube onlywhen wearing
shatterproof goggles and after discharging the high voltage completely,Keep others without shatter proof goggles away.
Before returning thereceiver to the user, performthe following safetychecks:
1. Inspect all lead dress to make certain that leads are not pinched or that hardware is not lodgedbetween the
chassis and other metal parts in the receiver.
2. Replace all protectivedevices such as non-metallic control knobs, insulating fishpapers, cabinet backs,
adjustment and compartment covers of shiedls, isolation resistor-capacitor networks, mechanical insulators etc.
3. Tobesure that not shock hazard exists, acheck for the presence of leakagecurrent shouldbe made at each
exposed metal part having areturn path to the chassis (antenna, cabinet metal, screw heads knobsand/or shafts,
escutcheon, etc.) in the following manner.
Plugthe AC line corddirectlyinto a120V,AC receptacle. (Do not usean Isolation Transformer during these
checks.) All checks must be repeated with the AC line cord plug connectionreversed. (Ifnecessary,anonpolarized
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