Panasonic Quasar PV-D300, Service Manual

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2 PREVENTION OF
ELECTRO STATIC
DISCHARGE (ESD) TO
ELECTROSTATICALLY
SENSITIVE (ES) DEVICES
Some semiconductor (solid state) devices can be damaged
easily by static electricity. Such components commonly are
called Electrostatically Sensitive (ES) Devices. Examples of
typical ES devices are integrated circuits and some field-effect
transistors
and semiconductor "chip" components. The
following techniques should be used to help reduce the
incidence of component damage caused by electro static
discharge (ESD).
1. Immediately before handling any semiconductor
component or semiconductor-equipped assembly, drain off
any ESD on your body by touching a known earth ground.
Alternatively, obtain and wear a commercially available
discharging ESD wrist strap, which should be removed for
potential shock reasons prior to applying power to the unit
under test.
2. After removing an electrical assembly equipped with ES
devices, place the assembly on a conductive surface such
as aluminum foil, to prevent electrostatic charge buildup or
exposure of the assembly.
3. Use only a grounded-tip soldering iron to solder or unsolder
ES devices.
4. Use only an antistatic solder removal device. Some solder
removal devices not classified as "antistatic (ESD
protected)" can generate electrical charge sufficient to
damage ES devices.
5. Do not use freon-propelled chemicals. These can generate
electrical charges sufficient to damage ES devices.
6. Do not remove a replacement ES device from its protective
package until immediately before you are ready to install it.
(Most replacement ES devices are packaged with leads
electrically shorted together by conductive foam, aluminum
foil or comparable conductive material).
7. Immediately before removing the protective material from
the leads of a replacement ES device, touch the protective
material to the chassis or circuit assembly into which the
device will be installed.
CAUTION :
Be sure no power is applied to the chassis or circuit, and
observe all other safety precautions.
8. Minimize bodily motions when handling unpackaged
replacement ES devices. (Otherwise harmless motion such
as the brushing together of your clothes fabric or the lifting
of your foot from a carpeted floor can generate static
electricity (ESD) sufficient to damage an ES device).
3 X-RADIATION (Model: B,
C, D, E, F)
WARNING :
1. The potential source of X-Radiation in EVF sets is the High
Voltage section and the picture tube.
2. When using a picture tube test jig for service, ensure that jig
is capable of handling 10 kV without causing X-Radiation.
NOTE :
It is important to use an accurate periodically calibrated
high voltage meter.
3. Measure the High Voltage. The meter (electrostatic type)
reading should indicate 2.2 kV±0.1 kV. If the meter
indication is out of tolerance, immediate service and
correction is required to prevent the possibility of premature
component failure. To prevent an X-Radiation possibility, it
is essential to use the specified picture tube.
4
PV-D300 / VM-D100 / PV-L550 / PV-L600 / PV-L650 / VM-L450