Sharp CX48K4, Service Manual

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CX48K4
SPECIFICATIONS
Convergence ................................................................................. Self Converging System
Focus ........................................................................... Electrstatic Focus High Bi-Potential
Sweep Deflection ................................................................................................... Magnetic
Intermediate Frequencies
Picture IF Carrier ............................................................................................... 38.9 MHz
Sound IF Carrier Frequency
5.5 MHz .......................................................................................................... 33.4 MHz
Colour Sub-Carrier Frequency ....................................................................... 34.47 MHz
Power Input .................................................................................... AC220 - 240V, 50/60 Hz
Power Consumption ..................................................................................................... 82 W
Audio Power Output Rating ......................................................................... 5.0 W (at Max.)
Speaker
Size .............................................................................................. 5
×
9 cm Elliptic (2 pcs)
Voice Coil Impedance ......................................................................... 16 ohms at 400 Hz
Aerial Input Impedance
VHF/UHF ....................................................................................... 75 ohm Unbalanced
Receiving Channels (PAL-B/G)
»
VHF ........................................................................................... AU0 thru AU12 ch
»
UHF ........................................................................................ AU28 thru AU69 ch
Receiving Frequency
»
VHF-Channels .................................................................... 44.25 thru 463.25 MHz
»
UHF-Channels ................................................................. 471.25 thru 863.25 MHz
Dimensions .............................................................................................. Width: 594.0 mm
Height: 465.0 mm
Depth: 484.0 mm
Weight (Approx.): 18.5 kg
Cabinet Material ................................................................................................. All Plastics
Specifications are subject to change without prior notice.
IMPORTANT SERVICE NOTES
Maintenance and repair of this receiver should be done 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 10k ohm Resistor in series with an insulated wire (such as a
test probe) between picture tube dag and 2nd anode 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 28.0 kV (at beam 0 mA) for the set.
2. To keep the set in a normal operation, be sure to make it function on 24.5 kV
±1.5 kV (at beam 1,100 mA) 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 a 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 and/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 dress 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 and etc.