Panasonic PV-DF2700-K, Service Manual

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There are special components used in this equipment which are important for
safety. These parts are marked by in the Schematic Diagrams, Circuit Board
Layout, Exploded Views and Replacement Parts List. It is essential that these
critical parts should be replaced with manufacturer’s specified parts to prevent X-
RADIATION, shock, fire, or other hazards. Do not modify the original design
without permission of manufacturer.
2. An Isolation Transformer should always be used during the servicing of
Combination VCR whose chassis is not isolated from the AC power line. Use a
transformer of adequate power rating as this protects the technician from
accidents resulting in personal injury from electrical shocks. It will also protect
Combination VCR from being damaged by accidental shorting that may occur
during servicing.
3. When servicing, observe the original lead dress, especially the lead dress in the
high voltage circuits. If a short circuit is found, replace all parts which have been
overheated or damaged by the short circuit.
4. After servicing, see to it that all the protective devices such as insulation
barriers, insulation papers, shield, and isolation R-C combinations are properly
installed.
5. Before turning the receiver on, measure the resistance between B+ line and
chassis ground. Connect (-) side of an ohmmeter to the B+ lines, and (+) side to
chassis ground. Each line should have more resistance than specified, as
follows :
B+ Line
Minimum Resistance
130 V
1 k (Cold chassis ground)
27 V
180 (Cold chassis ground)
17 V
110 (Cold chassis ground)
6. When the TV set is not used for a long period of time, unplug the power cord
from the AC outlet.
7. Potentials, as high as 34.5 kV are present when this TV set is in operation.
Operation of the TV set without the rear cover involves the danger of a shock
hazard from the TV set power supply. Servicing should not be attempted by
anyone who is not thoroughly familiar with the precautions necessary when
working on high voltage equipment. Always discharge the anode of the picture
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