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SAFETY PRECAUTIONS
1. Comply with all caution and safety-related notes provided
on the side of the cabinet, inside the cabinet, and on the
chassis,
2. When replacing a chassis in the cabinet, always be certain
that all the protective devices are installed properly, such
as control knobs, adjustment covers, shields and barriers.
3. Before replacing the back cover of the set, thoroughly
inspect the inside of the cabinet to see that no stray parts
or tools have been left inside.
ANTENNA COLD CHECK
Remove AC plug from the 120 VAC outlet and place a
jumper across the two blades. Connect one lead of an ohm-
meter to the jumpered AC plug, and touch the other lead to
each exposed antenna terminal (UHF and VHF antenna ter-
minals). The resistance must measure between 1M ohm and
5.2M ohm. Any resistance value below or above this range
indicates an abnormality which requires corrective action.
LEAKAGE CURRENT CHECK
Plug the AC line cord directly into a 120 VAC outlet. (Do not
use an isolation transformer for this check.) Use an AC volt-
meter, that has 5000 ohms per volt or more sensitivity.
Connect a 1500 ohm 10 watt resistor, paralleled by a 0.15 µF
150 VAC capacitor, between a known good earth ground
(water pipe, conduit, etc.) and all exposed metal parts of the
cabinet (antennas, handle bracket, metal cabinet, screw
heads, metal overlays, control shafts, etc.). Measure the AC
voltage across the 1500 ohm resistor. The AC voltage
should not exceed 750 mV. A reading exceeding 750 mV
indicates that a dangerous potential exists. The fault must
be located and corrected. Repeat the above test with the
receiver power plug reversed.
NEVER RETURN A RECEIVER TO THE CUSTOMER
WITHOUT TAKING THE NECESSARY CORRECTIVE ACTION.
SAFETY INSTRUCTIONS
— 2 —
READING SHOULD NOT EXCEED 750 mV.
(5000 ohms per volt or more sensitivity)
TELEVISION
RECEIVER
AC OUTLET
To be touched to all of exposed metal parts.
Voltmeter Hook-up for Leakage Current Check.
PRODUCT SAFETY NOTICE
When replacing components in a receiver, always keep in
mind the necessary product safety precautions. Pay special
attention to the replacement of components marked with a
star (#) in the parts list and in the schematic diagrams. To
ensure safe product operation, it is necessary to replace
those components with the exact same PARTS.
AC VOLTMETER
Good earth ground
1500 ohm
such as a water pipe,
10 watt
conduit, etc.
0.15 µF 150V AC
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