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4. Completely discharge the high pote ntial voltage of the
picture tube before handli ng. The pi cture tube is a
vacuum and if bro ken, the gl ass will explode.
5. When rep lacing a MAIN PC B in the cabinet, always
be certai n that all protective are installed properly
such as co ntrol knobs, adjustment co vers o r shie lds,
barri ers, iso lation resistor networks etc.
6. When se rvicing is re quired, observe the origin al lead
dressing. Extra precau tion sho uld be gi ven to a ssure
correct lead dressing in the high voltage area.
7. Keep wires away from high voltage or high te mpera
ture compone nts.
8. Befo re returning the set to the customer, al ways
perform an AC leaka ge current check on the exposed
meta llic parts of th e cabine t, such as anten nas,
termin als, screw heads, meta l overlay, control shafts,
etc., to be sure the set i s safe to operate without
danger of electrica l shock. Plu g the AC lin e cord
directly to the AC outlet (do not use a line iso lation
transformer d uring th is check). Use an AC voltmeter
havin g 5K ohms volt sen sitivity or more i n the
following manner.
Conne ct a 1.5 K ohm 10 watt resistor pa ralleled by a
0.15µF AC type capacito r, between a go od earth
ground (water pipe, conductor etc.,) and the exposed
metallic parts, one a t a ti me.
Measure the AC vol tage across the combination of
the 1 .5K ohm resistor and 0.15 uF capacitor. Re verse
the AC p lug at the AC o utlet and repea t the AC
volta ge measurements fo r each exposed metallic
part.
The me asured voltage must not exceed 0.3 V RMS.
This correspo nds to 0.5mA AC. Any val ue exceeding
this limit co nstitute s a poten tial sho ck hazard and
must be corrected immedia tely.
The resista nce me asureme nt shou ld be done
betwe en accessi ble exposed metal parts and power
cord plug prong s with th e power switch "ON". The
resi stance should be mo re tha n 6M o hms.
AC VOLTMETER
Goo d ea rth grou nd
su ch as th e wat er
p ip e ,
c o n du c t or ,
etc.
AC Leak age Curr ent Check
Pl ace this pro be
o n
e a c h
e x -
p os ed
me t al li c
part
- 3 -
PRODUCT SAFETY NOTICE
Many e lectrical an d mechanica l parts in this TV
receiver have special safety-related characteristics.
These characteri stics are offer passed unnoticed by
visual spection and the protecti on afforded by them
cannot necessari ly be obta ined by using replacement
compon ents rates for a hig her voltag e, wattage , etc.
The replacemen t parts w hich have these sp ecial
safety characteristics are identifie d by
the schematic diag ram and on the parts l ist.
Before replacin g any of these compo nents, rea d the
parts list in thi s manua l care fully. The use of
substitute re placemen t parts which do not have the
same safety chara cteristics as speci fied in the p arts
list may cre ate shock, fire, X-RAY RADIATION or
other h azards.
marks on
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