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5.
W hen rep la cing a M AIN PC B in th e cabinet,
a lw ays be certa in th a t all p ro tective are
installed properly such as co ntrol knobs,
a djustm e nt covers o r shields, barriers, isolation
re sisto r netw orks etc.
6.
W hen servicing is required, o b se rve the original
lead d ressing. Extra precaution should be given
to a ssu re co rre ct lead d re ssin g in th e high
voltage area.
7.
Keep w ire s a w a y from high vo lta g e o r high
te m p era ture com ponents.
8.
B efore retu rning th e set to th e custom er,
alw ays perform an A C leakage cu rre n t check
on th e e xposed m e ta llic parts o f th e cabinet,
such as antennas, te rm ina ls, screw heads, metal
o verla y, co n tro l sh afts, etc., to be su re th e set
is safe to o p e ra te w ith o u t d a n g e r o f ele ctrica l
shock. Plug th e A C line cord d ire c tly to the
A C o u tle t (do not use a line isola tion
tra n s fo rm e r durin g th is check). U se an AC
v o ltm e te r having 5K ohm s v o lt se nsitivity o r
m ore in the fo llo w in g m anner.
C on ne ct a 1.5K o hm 10 w a tt re sisto r paralleled
by a 0 .15 pF A C typ e ca pa citor, b etw e en a
good earth ground (w a te r pipe, co n d u cto r etc.,)
and th e e xpo sed m e ta llic parts, o ne at a tim e.
M easure th e A C vo lta g e a cross the combination
o f
th e 1.5K o hm re s is to r and 0 .1 5 uF
capacitor. R e ve rse
o utle t and repeat th e A C vo lta g e m easurem ents
fo r each exposed m e ta llic part.
T he m easured vo lta g e m ust not exceed 0.3V
RMS.
T his co rre sp o n d s to 0 .5 m A A C . A n y value
excee ding th is lim it co n stitu te s a potential
sh o ck hazard and m ust be corrected
im m ediately.
T he resistance m easurem ent should be done
betw een a ccessible exposed m etal parts and
p ow er cord plug prongs w ith th e p o w e r sw itch
"O N ". T he re sista n ce should be m ore
6M ohm s.
A C V O L T M E T E R
Good earth ground
s u c h as th e w a te r
1500 ohmi, lOwatt
- p ip e ,
c o n d u c to r,
etc.
A C L eakage C u rren t C heck
th e A C plug at th e AC
than
Place this probe
on each exposed
m etallic part
P R O D U C T S A F E T Y N O T I C E
M any e le ctrica l and m ech an ical parts in th is
apparatus have special safety-related
characteristics.
T hese characte ristics are o ffe r passed
unnoticed by visua l spection and the protection
a fforded by th em ca nn ot n ece ssarily be obtained
by using rep la ce m e nt co m p on en ts rates fo r a
higher voltage, w attage, etc.
T he rep la ce m e nt parts w hich have these
sp ecial sa fety ch a ra cte ristics are identified by A
m arks on th e s c h e m a tic d ia g ra m and on th e parts
list.
B efore replacing any o f th e se com ponents,
read th e parts list in th is m anual ca re fully. The
use o f
s u b s titu te re p la c e m e n t parts w h ich do not
have th e sam e sa fety ch a ra cte ristics as specified
in th e parts list m ay c re a te shock, fire , o r o th e r
hazards.
9.
M ust be su re th a t th e g ro u n d w ire o f th e AC
inlet is co nn ecte d w ith th e gro un d o f th e
apparatus properly.
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