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COLOR TV
SERVICE MANUAL
CHASSIS : CW62B
MODEL: 21FURLX
MODEL: 21FU1RLX-TV
CAUTION
BEFORE SERVICING THE CHASSIS,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
Apr., 2007
P/NO.: MFL31616438 Printed in China
CONTENTS
Contents ....................................................................................................2
Safety Precautions....................................................................................3
Control Descriptions ................................................................................4
Specifications............................................................................................7
Adjustment Instructions...........................................................................8
SVC Remocon .........................................................................................13
Trouble Shooting ....................................................................................14
Printed circuit board...............................................................................17
Block Diagram.........................................................................................19
Exploded View.........................................................................................20
Exploded View Parts List .......................................................................21
Replacement Parts List ..........................................................................22
SVC. Sheet...................................................................................................
-2-
SAFETY PRECAUTIONS
IMPORTANT SAFETY NOTICE
Many electrical and mechanical parts in this chassis have special safety-related characteristics. These parts are identified by in the
Schematic Diagram and Replacement Parts List.
It is essential that these special safety parts should be replaced with the same components as recommended in this manual to prevent
X-RADIATION, Shock, Fire, or other Hazards.
Do not modify the original design without permission of manufacturer.
General Guidance Before returning the receiver to the customer,
always perform an AC leakage current check on the exposed
An isolation Transformer should always be used during the metallic parts of the cabinet, such as antennas, terminals, etc., to
servicing of a receiver whose chassis is not isolated from the AC be sure the set is safe to operate without damage of electrical
power line. Use a transformer of adequate power rating as this shock.
protects the technician from accidents resulting in personal injury
from electrical shocks. Leakage Current Cold Check(Antenna Cold Check)
With the instrument AC plug removed from AC source, connect an
It will also protect the receiver and it's components from being electrical jumper across the two AC plug prongs. Place the AC
damaged by accidental shorts of the circuitry that may be switch in the on position, connect one lead of ohm-meter to the AC
inadvertently introduced during the service operation. plug prongs tied together and touch other ohm-meter lead in turn to
each exposed metallic parts such as antenna terminals, phone
If any fuse (or Fusible Resistor) in this TV receiver is blown, jacks, etc.
replace it with the specified. If the exposed metallic part has a return path to the chassis, the
measured resistance should be between 1M and 5.2M.
When replacing a high wattage resistor (Oxide Metal Film Resistor, When the exposed metal has no return path to the chassis the
over 1W), keep the resistor 10mm away from PCB. reading must be infinite.
An other abnormality exists that must be corrected before the
Keep wires away from high voltage or high temperature parts. receiver is returned to the customer.
Due to high vacuum and large surface area of picture tube, Leakage Current Hot Check (See below Figure)
extreme care should be used in handling the Picture Tube. Do not Plug the AC cord directly into the AC outlet.
lift the Picture tube by it's Neck. Do not use a line Isolation Transformer during this check.
Connect 1.5K/10watt resistor in parallel with a 0.15uF capacitor
X-RAY Radiation between a known good earth ground (Water Pipe, Conduit, etc.)
and the exposed metallic parts.
Warning: Measure the AC voltage across the resistor using AC voltmeter
with 1000 ohms/volt or more sensitivity.
The source of X-RAY RADIATION in this TV receiver is the High Reverse plug the AC cord into the AC outlet and repeat AC voltage
Voltage Section and the Picture Tube. measurements for each exposed metallic part. Any voltage
For continued X-RAY RADIATION protection, the replacement measured must not exceed 0.75 volt RMS which is corresponds to
tube must be the same type tube as specified in the 0.5mA.
Replacement Parts List. In case any measurement is out of the limits specified, there is
possibility of shock hazard and the set must be checked and
repaired before it is returned to the customer.
To determine the presence of high voltage, use an accurate high
impedance HV meter. Leakage Current Hot Check circuit
Adjust brightness, color, contrast controls to minimum. AC Volt-meter
Measure the high voltage.
The meter reading should indicate
23.5