Important Service Notes - Sharp 37DT Service Manual

Maintenance and repair of this receiver should be carried out by qualified service personnel only.
SERVICING OF HIGH VOLTAGE SYSTEM AND PICTURE TUBE
When servicing the high voltage system, remove static charge from it by connecting a 10 k ohm resistor in
series with an insulated wire (such as a test probe) between picture tube ground tag and high voltage lead
(AC line cord should be disconnected from AC outlet).
1. Picture tube in this receiver employs integral implosion protection.
2. Replace with tube of the same type number for continued safety.
3. Do not lift picture tube by the neck.
4. Handle the picture tube only when wearing shatterproof goggles and after discharging the high voltage
completely.
X-RAY
This receiver is designed so that any X-Ray radiation is kept to an absolute minimum. Since certain
malfunctions or servicing may produce potentially hazardous radiation with prolonged exposure at close
range, the following precautions should be observed.
1 . When repairing the circuit, be sure not to increase the high voltage to more than
30.0 kV (at beam 1000 uA) for the set.
2. To keep the set in a normal operation, be sure to make it function on 23.5 kV ± 1.5 kV (at beam 800 p.A),
in the case of the set. The set has been factory adjusted to the above mentioned high voltage. If there
is a possibility that the high voltage fluctuates as result of the repairs, never forget to check for such high
voltage after the work.
3. Do not substitute a picture tube with unauthorized types or brands which may cause excess X-Ray
radiation.
BEFORE RETURNING THE RECEIVER
Before returning the receiver to the user, perform the following safety checks.
1 . Inspect all lead insulation to make certain that leads are not pinched or that hardware is not lodged
between the chassis and other metal parts in the receiver.
2. Inspect all protective devices such as non-metallic control knobs, insulating fishpapers, cabinet backs,
adjustment and compartment covers or shields, isolation resistor-capacity networks, mechanical
insulators, etc.
IMPORTAMT SERVICE NOTES
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