Important Safety Precautions - Sylvania 6319CCB Service Manual

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 Circuit
1. Before returning an instrument to the cus-
tomer,
always make a safety check of the entire
instrument, including, but not limited to, the following
items:
a. Be sure that no built-in protective devices are defec-
tive and have been defeated during servicing. (1)
Protective shields are provided on this chassis to
protect both the technician and the customer. Cor-
rectly replace all missing protective shields, includ-
ing any removed for servicing convenience. (2)
When reinstalling the chassis and/or other assembly
in the cabinet, be sure to put back in place all
protective devices, including but not limited to, non-
metallic control knobs, insulating fishpapers, adjust-
ment and compartment covers/shields, and isola-
tion resistor/capacitor networks.
this instrument or permit it to be operated
without all protective devices correctly in-
stalled and functioning. Servicers who de-
feat safety features or fail to perform safety
checks may be liable for any resulting dam-
age.
Be sure that there are no cabinet openings through
b.
which an adult or child might be able to insert their
fingers and contact a hazardous voltage. Such
openings include, but are not 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 cover.
c. Antenna Cold Check -
plug removed from any AC source, connect an
electrical jumper across the two AC plug prongs.
Place the instrument AC switch in the on position.
Connect one lead of an ohmmeter to the AC plug
prongs tied together and touch the other ohmmeter
lead in turn to each tuner antenna input exposed
terminal screw and, if applicable, to the coaxial
connector. If the measured resistance is less than
1.0 megohm or greater than 5.2 megohm, an abnor-
mality exists that must be corrected before the in-
strument is returned to the customer. Repeat this
test with the instrument AC switch in the off position.
d. Leakage Current Hot Check -
ment completely reassembled, plug the AC line cord
directly into a 120V AC outlet. (Do not use an isola-
tion transformer during this test.) Use a leakage
FNI
Do not operate
With the instrument AC
With the instru-
current tester or a metering system that complies
with American National Standards Institute (ANSI)
C101.1 Leakage Current for Appliances and Under-
writers Laboratories (UL) 1410, (50.7). With the
instrument AC switch first in the on position and then
in the off position, measure from a known earth
ground (metal water pipe, conduit, etc.) to all ex-
posed metal parts of the instrument (antennas, han-
dle brackets, metal cabinet, screw heads, metallic
overlays, control shafts, etc.), especially any ex-
posed metal parts that offer an electrical return path
to the chassis. Any current measured must not
exceed 0.5 milli-ampere. Reverse the instrument
power cord plug in the outlet and repeat the test.
READING SHOULD
NOT BE ABOVE 0.5 mA
DEVICE
BEING
TESTED
ALSO TEST WITH
PLUG REVERSED
USING AC
ADAPTER PLUG
AS REQUIRED
ANY MEASUREMENTS NOT WITHIN THE LIMITS
SPECIFIED HEREIN INDICATE A POTENTIAL
SHOCK HAZARD THAT MUST BE ELIMINATED
BEFORE RETURNING THE INSTRUMENT TO
THE CUSTOMER OR BEFORE CONNECTING
THE ANTENNA OR ACCESSORIES.
e. -Radiation and High Voltage Limits -
X
cause the picture tube is the primary potential
source of X-radiation in solid-state TV receivers, it
is specially constructed to prohibit X-radiation emis-
sions. For continued X-radiation protection, the re-
placement picture tube must be the same type as
the original. Also, because the picture tube shields
and mounting hardware perform an X-radiation pro-
tection function, they must be correctly in place.
High voltage must be measured each time servicing
1-2-1
LEAKAGE
CURRENT
TESTER
+
TEST ALL EXPOSED
METAL SURFACES
EARTH
GROUND
_
Be-
SFTY_2