IMPORTANT SAFETY PRECAUTIONS
Prior to shipment from the factory, our products are strictly inspected for recognized product safety and electrical
codes of the countries in which they are to be sold. However, in order to maintain such compliance, it is equally
important to implement the following precautions when a set is being serviced.
Safety Precautions for TV CircuitAC line cord directly into a 120 V AC outlet. (Do
not use an isolation transformer during this
1. Before returning an instrument to the
test.) Use a leakage current tester or a
customer, always make a safety check of the metering system that complies with American
entire instrument, including, but not limited to, the
National Standards Institute (ANSI) C101.1
following items:Leakage Current for Appliances and
a. Be sure that no built-in protective devices are Underwriters Laboratories (UL) 1410, (50.7).
defective and have been defeated during With the instrument AC switch first in the on
servicing. (1) Protective shields are provided position and then in the off position, measure
on this chassis to protect both the technician from a known earth ground (metal water pipe,
and the customer. Correctly replace all missing conduit, etc.) to all exposed metal parts of the
protective shields, including any removed for instrument (antennas, handle brackets, metal
servicing convenience. (2) When reinstalling cabinet, screw heads, metallic overlays, control
the chassis and/or other assembly in the shafts, etc.), especially any exposed metal
cabinet, be sure to put back in place all parts that offer an electrical return path to the
protective devices, including but not limited to, chassis. Any current measured must not
nonmetallic control knobs, insulating exceed 0.5 milli-ampere. Reverse the
fishpapers, adjustment and compartment instrument power cord plug in the outlet and
covers/shields, and isolation resistor/capacitor repeat the test.
networks. Do not operate this instrument or
permit it to be operated without all READING SHOULD
protective devices correctly installed and
NOT BE ABOVE 0.5 mA
functioning. Servicers who defeat safety
features or fail to perform safety checks
LEAKAGE
may be liable for any resulting damage.DEVICECURRENT
TESTERBEING
b. Be sure that there are no cabinet openings
through which an adult or child might be able to TESTED_+
insert their fingers and contact a hazardous TEST ALL EXPOSED
voltage. Such openings include, but are not METAL SURFACES
limited to, (1) spacing between the picture tube
and the cabinet mask, (2) excessively wide
cabinet ventilation slots, and (3) an improperly
fitted and/or incorrectly secured cabinet back ALSO TEST WITH
PLUG REVERSED
cover.
USING AC
c. Antenna Cold Check - With the instrument AC EARTH
plug removed from any AC source, connect an ADAPTER PLUG
AS REQUIREDGROUND
electrical jumper across the two AC plug
prongs. Place the instrument AC switch in the
ANY MEASUREMENTS NOT WITHIN THE
on position. Connect one lead of an ohmmeter
to the AC plug prongs tied together and touch LIMITS SPECIFIED HEREIN INDICATE A
POTENTIAL SHOCK HAZARD THAT MUST
the other ohmmeter lead in turn to each tuner
antenna input exposed terminal screw and, if BE ELIMINATED BEFORE RETURNING THE
INSTRUMENT TO THE CUSTOMER OR
applicable, to the coaxial connector. If the
measured resistance is less than 1.0 megohm BEFORE CONNECTING THE ANTENNA OR
ACCESSORIES.
or greater than 5.2 megohm, an abnormality
exists that must be corrected before the e. X-Radiation and High Voltage Limits -
instrument is returned to the customer. Repeat Because the picture tube is the primary
this test with the instrument AC switch in the off potential source of X-radiation in solid-state TV
position.receivers, it is specially constructed to prohibit
X-radiation emissions. For continued X-
d. Leakage Current Hot Check - With the
instrument completely reassembled, plug the radiation protection, the replacement picture
tube must be the same type as the original.
2-1TVN_ISP |
ACEC
