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SAFETY PRECAUTIONS
WARNING
Before servicing this unit, familiarize yourself with the following precautions:
1.Many electrical and mechanical parts in this
chassis have special safety characteristics that
often pass unnoticed and the protection
afforded
by them cannot
necessarily be
obtained by using replacement components
rated for higher voltage,
wattage,
etc.
Replacement parts that have these special
safety characteristics are identified in this
manual
and
its supplements:
electrical
components
having
such
features
are
identified by A\ in 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 that do
not have the same safety characteristics as
specified in the parts list may create shock,
fire, or other hazards.
2.Before returning the set to the customer,
always do an AC leakage current check on the
AC Outlet
At 5000 Q per volt or greater sensitivity,
the reading should not exceed 0.75 V.
Place the probe on each exposed metalic part.
exposed metal parts of the cabinet, such as
terminals, screw heads, and metal overlays, to
be sure the set is safe to operate danger of
electrical shock. Plug the AC line cord directly
into a 120 V AC outlet(USA Version) or 230 V
AC outlet(EU Version). (Do not use a line
isolation transformer during this check.) Be
sure your AC voltmeter has a sensitivity of
5000 Q per volt or greater. Then connect a
1500 Q 10 watt resistor, paralleled by a 0.15 pF
150 V AC capacitor, between a known good
earth ground(such as a water pipe, or conduit)
and the exposed metalic is parts, one at a
time. Measure the AC voltage across the
combination of a 1500 Q resistor and a 0.15 pF
capacitor. Reverse the AC plug at the AC outlet
and repeat AC voltage measurements for each
exposed metalic part. Voltage measured must
not exceed 0.75 V RMS. This corresponds to
0.2 mA AC. Any value exceeding this limit
constitutes a potential shock hazard and must
be corrected immediately.
AC Voltmeter
Good earth ground, such as
a water pipe or.conduct
0.15 uF 150 VAC.
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