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CAUTION: Do not attempt to modify this product in any way. Unauthorized
modifications will not only void the warranty, but may lead to your being liable
for any resulting property damage or user injury.
Service work should be performed only afer you are thoroughly familiar with all
of the following safety checks and servicing guidelines. To do otherwise, increases the risk of potential hazards and injury to the user.
SAFETY CHECKS
After the orginal service problem has been corrected, a check should be made of
the follwoing:
SUBJECT : FIRE & SHOCK HAZARD
1. Be sure that all components are positioned in such a way as to aboid possibility
of adjacent component shorts. This is especially important on those chassis
which are transported to and from the repair shop.
2. Never release a repair unless all protective devices such as insulators, barriers,
covers, shields, strain reliefs, and other hardware have been reinstalled per
original design.
3. Soldering must be inspected to discover possible cold solder joints, frayed
leads, damaged insulation (including a.c. cord), solder splahes or sharp solder
points. Be certain to remove all loose foreigh particals.
4. Check for physical evidence of damage or deterioration to parts and compo-
nents, and replace if necessary follw original layout, lead length and dress.
5. No leads or components should touch a receiving tube or a resistor rated at 1
watt or more. Lead tension around protruding metal surfaces must be avoided.
6. All critical components such as fuses, flameproof resistors, capacitor, etc. must
be replaced with exact factory types. Do not use replacement components other
than those specified or make unrecommended circuit modifications.
7. after re-assembly of the set always perform an A.C. leakage test on all exposed
metallic parts of the cabinet, (the channel selector knob, antenna terminals,
handle and screws) to be sure the set is safe to operate without danger of electrical shock. Do not use a line isolation transformer during this test. Use an
A.C. voltmeter, having 5000 ohms per volt or more sensitivity, in the following
manner: connect a 1500 ohm 10 watt resistor, paralleled by a 15 mfd. 150V
A.C. type capacitor between a known good earth ground (9water pipe, conduit,
etc.) and the exposed metallic part, one at a time. Measure the A.C. voltage
across the combination of 1500 ohm resistor and 0.15 MFD capacitor. Reverse
the A.C. plug and repeat A.C. voltage measurements for each exposed metallic
part. Voltage measured must not exceed 0.75 volts. R.M.S. This corresponds to
0.5 milliamp A.C Any value exceeding this limit constitutes a potential shock
hazard and must be corrected immediately.
GRAPHCI SYMBOLS:
The lightning flash with arrowhead symbol, within an equilateral triangle, is intended to alert the service personnel to the persence of
uninsulated “dangerous voltage’ that may be of sufficienty magnitude to constitute a risk of electric shock.
The exclamation point within an equilateral triangle is intended to
alert the service personnel to the presence of important safety information in service literature.
Fuse symbol is printed on pcb adjacent to the fuse, with
“RISK OF FIRE REPLACE FUSE AS MARKED”. The
symbol is explained in the service manual with the following wording or equivalent..
“CAUTION: FOR CONTINUED PROTECTION AGAINST FIRE
HAZARD, REPLACE ONLY WIHT SAME TYPE (4A, 12V)” and
“ATTENTION: AFIN D’ASSU UNE PROTECTION PERMANENTE CONTRE LES RISQUES D’INCENDIE, REMPLACER
UNIQUEMENT PAR UN FUSIBLE DE MEME TYPE ET DE “4A,
125V
”.
SUBJECT: X-RADIATION
1. Be sure procedures and instructions to all service personnel cover the subject of
X-rays in current T.V. receivers is the picture tube. However, this tube does not
emit X-rays when the high voltage is at the factory specified level. The proper
value is given in the applicalbe schematic. Operation at higher voltages may
cause a failure of the picture tube or high voltage supply and, under certain circumstances, may produce radiation in excess of desirable levels.
2. Only factory specified C.R.T. anode connectors must be used.
Degaussing shields also serve as X-rays shield in color sets. Always re-install
them.
3. It is essential that the serviceman has available and accurate and reliable high
voltage meter. The calibration of the meter should be checked perio-dically
against a reference standard. Such as the one available at your distributor.
4. When the high voltage circuitry is operating properly there is no possibility of
an X-radiation problem. Every tice a color chassis is serviced, the brightness
should be run up and down while monitoring the high voltage with a meter to
be certain that the high voltage does not exceed the specified value and that it is
regulating correctly. We suggest that you and your service organization review
test procedures so that voltage regulation is always cecked as a standard servicing procedure. And that the high voltage reading be recorded on each customer’s invoice.
5. When troubleshooting and making test measurements in a receiver with a
problem of excessive high voltage, avoid being unnecessarily close to the picture tub eand the high voltage compartment.
Do not operat the chassis longer than is necessary to locate the cause of excessive voltage.
6. Refer to HV, B+and Shutdown adjustment procedures described in the appropriate schematic and diagrams(where used).
SUBJECT: IMPLOSION
1. All direct viewed picture tubes are equipped with an integral implosion protection system, but care should be taken to avoid damage during installation.
Avoid scratching the tube. If scratched, replace it.
2. Use only recommended factory replacement tubes.
SUBJECT: TIPS ON PROPER INSTALLATION
1. Never install any receiver in closed-in recess, cubbyhole or closely fitting shelf
space over, or close to heat duct, or in the path of heated air flow.
2. Avoid conditions of high humidity such as: Outdoor patio installations where
dew is a factor, Near steam radiators where steam leakage is a factor, etc.
3. Avoid placement where draperies may obstruct rear venting. The customer
should also avoid the use of decorative scarves or other coverings which might
obstruct ventilation.
4. Wall and shelf mounted installations using a commercial mounting kit, must
follow the factory approved mounting instructions. A receiver mounted to a
sheif or platform must retain its original feet(or the equivalent thickness in
spacers) to provide adequate are flow across the bolts or screws used for fasteners must not touch and parts or wiring. Perform leakage test on customized
installations.
5. Caution customers against the mounting of a receiver on sloping shelf or a tilted position, unless the receiver is properly secured.
6. A receiver on a roll-about cart should be stable on its mounting to the cart.
Caution the customer on the hazards of trying to roll a cart with small casters
across thresholds or deep pile carpets.
7. Caution customers against the use of a cart or stand which has not been listed
by underwriters laboratories, in. For use with their specific model of telvision
receiver or generically approved for use with T.V.’s of the same or larger
screen size.
PRODUCT SAFETY SERVICING GUIDELINES FOR COLOR TELEVISION RECEIVERS