Trident IS-TVHD30, Руководство по обслуживанию

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beam current should be within 35KV on condition that the main power(B+) voltage is DC140V. And it
should not exceed 36KV in any condition.
1. Be sure procedures and instructions to all service personnel cover the subject of X-rays in current
TV 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 applicable 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-ray shield in color sets. Always re-install them.
3. It is essential that the serviceman has available an accurate and reliable high voltage meter. The
calibration of the meter should be checked periodically 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 time 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 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. Too excessive voltage will cause harmful X-ray.
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.
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 airflow.
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 shelf or platform must retain its original
feet(or the equivalent thickness in spacers) to provide adequate are flow across the bottom, blots 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.