Improtant Service Notes
PRODUCT SAFETY SERVICING GUIDELINES FOR AUDIO - VIDEO PRODUCTS
CAUTION : Do not attempt to modify this product in any way Unauthorized modifications will GRAPHIC SYMBOLS :
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 afters you are thoroughly familiar with all The lightning flash with arrowhead symbol,
of the following safety checks and servicing guidelines. To do otherwise, increases the risk of within an equilateral triangle, is intended to alert
potential hazards injury to the user. the service personnel to the presence of uninsulated "dangerous
voltage" that may be of sufficienty magnitude to constitute a risk of
SAFETY CHECKS electric shock.
After the original service problem has been corrected, a check should be made of the The exclamation point within an equilateral triangle is intended to alert
following : the service personnel to the presence of important safety information
in service literature.
SUBJECT FIRE & SHOCK HAZARD
Fuse symbol is printed on pcb adjacent to the fuse, with "RISK OF FIRE
1. Be sure that all components are positioned in such a way as to avoid possibility of adjacent REPLACE FUSE AS MARKED". The symbol is explained in the service
component shorts. This is especially important on those chassis which are transported to manual with the following wording or equivalent.
and from the repair shop.
2. Never release a repair unless all protective devices such as Insulators, barriers, covers,"CAUTION : FOR CONTINUED PROTECTION AGAINST FIRE HAZARD, REPLACE ONLY
shields, strein reliefs, and other hardware have been reinstalled per original design.WITH SAME TYPE (6.3A, 250V)" and "ATTENTION : AFIN D'ASSU UNE PROTECTION
3. Soldering must be inspected to discover possible cold solder joints frayed leads, damagedPERMANENTE CONTRE LES RISQUES D'INCENDIE, REMPLACER UNIQUEMENT PAR
insulation (Including A.C. cord), solder splashes or sharp solder points. Be certain toUN FUSIBLE DE MEME TYPE ET DE "6.3A, 250V".
remove all loose foreign particals.
4. Check for physical evidence of damage or deterioration to parts and components, andSUBJECT : X-RADIATION
replace if necessary follow 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.1. Be sure procedures and instructions to all service personnel cover the subject of X-rays in
Lead tension around protruding metalsurfaces must be avoided. current T.V receivers is the picture tube.
6. All critical components such as fuses, flameproof resistors, capacitor, etc must be replaced However, this tube does not emit X-rays when the high voltage is at the factory specified
with exact factory types. Do not use replacement components other than those specified or level. The proper value is given in the applicable schematic.
make unrecommended circuit modifications. Operation at higher voltages may cause a failure of the picture tube or high voltage supply
7. After re-assembly of the set always perform an A.C. leakage test on all exposed metallic and, under certain circumstances, may produce radiation in excess of desirable levels.
parts of the cabinet, (the channel selector knob, antenna terminals, handle and screws) to 2. Only factory specified C.R.T anode connectors must be used.
be sure the set is safe to operate without danger of electrical shock. Do not use a line Degaussing shields also serve as X-ray shield in color sets. Always re-install them.
Isolation transformer during this test. Use an A.C voltmeter, having 5000 ohms per volt or3. It is essential that the serviceman has available an accurate and reliable high voltage meter.
more sensitivity, in the following manner : connect a 1500 ohm 10 watt resistor, paralleled The calibration of the meter should be checked perio - dically against a reference standard.
by a 15 mfd. 150V A.C. type capacitor between a known good earth ground ( 9 water pipe, Such as the one available at your distributor.
conduit, etc ) and the exposed metallic parts, one at a time. Measure the A.C. voltage across4. When the high voltage circuitry is operating properly there is no possibility of an X-radiation
the combination of 1500 ohm resistor and 0.15 MFD capacitor. Reverse the A.C plug and problem. Every time a color chassis is serviced, the brightness should be run up and down
repeat A.C. voltage measurements for each exposed metallic part. Voltage measured must while monitoring the high voltage with a meter to be certain that the high voltage does not
not exceed 0.75 volts R.M.S. This corresponds to 0.5 milliamp A.C. Any value exceeding exceed the specified value and that it is regulating correctly. We suggest that you and your
this limit constitutes a potential shock hazard and must be corrected immediately service organization review test procedures so that voltage regulation is always checked 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 tube and the high
voltage compartment.
Do not operate 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 integeral implosion protection system, 4. Wall and shelf mounted installations using a commercial mounting kit, must follow the
but care should be taken to avoid damage during installation. Avoid scratching the tube. If factoryapproved mounting instructions. A receiver mounted to a shelf or platform must retain
scratched, replace it. its original feet (or the equivalent thickness in spacers) to provide adequate are flow across
2. Use only recommended factory replacement tubes. the bottom, bolts or screws used for fasteners must not touch and parts or wiring. Perform
leakage test on customized installations.
SUBJECT : TIPS ON PROPER INSTALLATION5. Caution customers against the mounting of a receiver on sloping shelf or a tilted position,
unless the receiver is properly secured.
1. Never install any receiver in closed-in recess, cubbyhole or closely fitting shelf space over, or6. A receiver on a roll-about cart should be stable on its mounting to the cart. Caution the
close to heat duct, or in the path of heated air flow. customer on the harzards of trying to roll a cart with small casters across thresholds or deep
2. Avoid conditions of high humidity such as : Outdoor patio installations where dew is a factor. pile carpets.
Near steam radiators where steam leakage is factor, etc.7. Caution customers against the use of a cart or stand which has not been listed by
3. Avoid placement where draperies may obstruct rear venting. The customer should also underwriters laboratories, inc. For use with their specific model of television receiver or
avoid the use of decorative scarves or other coverings which might obstruct ventilation. generically approved for use with T.V.?s of the same or larger screen size.
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ACEC
