Panasonic DMR-EH80VEG, Service Manual

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1 INTRODUCTION
This service manual contains technical information which will
allow service personnel to understand and service these
models.
Please place orders using the parts list and not the drawing
reference numbers.
1. This service manual does not contain the following
information, because of the impossibility of servicing at
component level.
·
Schematic Diagram, Block Diagram and P.C.B. layout
of Digital P.C.B.
· Parts List for individual parts of Digital P.C.B.
· Exploded View and Parts List for individual parts of RAM
drive.
2. The following categories are recycling module part. Please
send them to Central Repair Center.
· Digital P.C.B.:
DMR-EH80VEB: RFKBEH80VEB
DMR-EH80VEG: VEP79108E
· RAM Drive: VXY1872
3. If the circuit is changed or modified, this information will be
followed by supplement service manual to be filed with
original service manual.
4. Adjustment procedures, Disassembly Procedures and
Assembly Procedures for VCR Mechanism Chassis are
separate volume from this service manual. Please refer to
the service manual for R4 Mechanism Chassis for EURO
model (MAD0403002C2).
2 SAFETY PRECAUTIONS
2.1. GENERAL GUIDELINES
1. Be careful during removing metal parts, sharp edges.
2. When servicing, observe the original lead dress. If a short
circuit is found, replace all parts which have been
overheated or damaged by the short circuit.
3. After servicing, see to it that all the protective devices such
as insulation barriers, insulation papers shields are properly
installed.
4. After servicing, make the following leakage current checks
to prevent the customer from being exposed to shock
hazards.
2.1.1. LEAKAGE CURRENT COLD
CHECK
1. Unplug the AC cord and connect a jumper between the two
prongs on the plug.
2. Measure the resistance value, with an ohmmeter, between
the jumpered AC plug and each exposed metallic cabinet
part on the equipment such as screw heads, connectors,
control shafts, etc. When the exposed metallic part has a
return path to the chassis, the reading should be between
1M
Ω
and 5.2M
Ω
.
When the exposed metal does not have a return path to
the chassis, the reading must be infinity.
Figure 1
2.1.2. LEAKAGE CURRENT HOT CHECK
1. Plug the AC cord directly into the AC outlet. Do not use an
isolation transformer for this check.
2. Connect a 1.5k
Ω
, 10 watts resistor, in parallel with a 0.15µF
capacitors, between each exposed metallic part on the set
and a good earth ground such as a water pipe, as shown in
Figure 1.
3. Use an AC voltmeter, with 1000 ohms/volt or more
sensitivity, to measure the potential across the resistor.
4. Check each exposed metallic part, and measure the
voltage at each point.
5. Reverse the AC plug in the AC outlet and repeat each of the
above measurements.
6. The potential at any point should not exceed 0.75 volts
RMS. A leakage current tester (Simpson Model 229 or
equivalent) may be used to make the hot checks, leakage
current must not exceed 1/2 milliampere. In case a
measurement is outside of the limits specified, there is a
possibility of a shock hazard, and the equipment should be
repaired and rechecked before it is returned to the
customer.
5
DMR-EH80VEG / DMR-EH80VEB