SERVICING PRECAUTIONS
CAUTION: Before servicing receivers covered by this service manual and its supplements and addenda, read and follow the SAFETY PRECAUTIONS on page 3 of this publication.
NOTE: If unforeseen circumstances create conflict between the following servicing precautions and any of the safety precautions on page 3 of this publication, always follow the safety precautions. Remember: Safety First.
General Servicing Precautions
1.Always unplug the receiver AC power cord from the AC power source before;
a.Removing or reinstalling any component, circuit board module or any other receiver assembly.
b.Disconnecting or reconnecting any receiver electrical plug or other electrical connection.
c.Connecting a test substitute in parallel with an electrolytic capacitor in the receiver.
CAUTION: A wrong part substitution or incorrect polarity installation of electrolytic capacitors may result in an explosion hazard.
d.Discharging the picture tube anode.
2.Test high voltage only by measuring it with an appropriate high voltage meter or other voltage measuring device (DVM, FETVOM, etc) equipped with
asuitable high voltage probe.
Do not test high voltage by "drawing an arc".
3.Discharge the picture tube anode only by (a) first connecting one end of an insulated clip lead to the degaussing or kine aquadag grounding system shield at the point where the picture tube socket ground lead is connected, and then (b) touch the other end of the insulated clip lead to the picture tube anode button, using an insulating handle to avoid personal contact with high voltage.
4.Do not spray chemicals on or near this receiver or any of its assemblies.
5.Unless specified otherwise in this service manual, clean electrical contacts only by applying the following mixture to the contacts with a pipe cleaner, cotton- tipped stick or comparable
CAUTION: This is a flammable mixture.
Unless specified otherwise in this service manual, lubrication of contacts in not required.
6.Do not defeat any plug/socket B+ voltage interlocks with which receivers covered by this service manual might be equipped.
7.Do not apply AC power to this instrument and/or any of its electrical assemblies unless all
8.Always connect the test receiver ground lead to the receiver chassis ground before connecting the test receiver positive lead.
Always remove the test receiver ground lead last.
9.Use with this receiver only the test fixtures specified in this service manual.
CAUTION: Do not connect the test fixture ground strap to any heat sink in this receiver.
Electrostatically Sensitive (ES) Devices
Some semiconductor
1.Immediately before handling any semiconductor component or
2.After removing an electrical assembly equipped with ES devices, place the assembly on a conductive surface such as aluminum foil, to prevent electrostatic charge buildup or exposure of the assembly.
3.Use only a
4.Use only an
5.Do not use
6.Do not remove a replacement ES device from its protective package until immediately before you are ready to install it. (Most replacement ES devices are packaged with leads electrically shorted together by conductive foam, aluminum foil or comparable conductive material).
7.Immediately before removing the protective material from the leads of a replacement ES device, touch the protective material to the chassis or circuit assembly into which the device will be installed.
CAUTION: Be sure no power is applied to the chassis or circuit, and observe all other safety precautions.
8.Minimize bodily motions when handling unpackaged replacement ES devices. (Otherwise harmless motion such as the brushing together of your clothes fabric or the lifting of your foot from a carpeted floor can generate static electricity sufficient to damage an ES device.)
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