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Colour Television CE25B2-C Service Manual CE25B2-C (W.Europe) CE25B2-C Service Ref. No. PRODUCT CODE: 111327615 ORIGINAL VERSION: Chassis No. EB4-A Note This TV receiver will not work properly in foreign countries where the television transmission system and power source differ from the design specifications.
SAFETY PRECAUTION 1: An isolation transformer should be connected in the 3: When replacing a chassis in the cabinet, always be power line between the receiver and the AC line when certain that all the protective devices are installed a service is performed on the primary of the converter properly, such as, control knobs, adjustment covers or transformer of the set.
CIRCUIT DESCRIPTION 1. POWER SUPPLY control) The chroma signal is divided into R-Y and B-Y The power supply circuit of the EB4-A chassis is chroma signals, demodulated in IC201, and output from composed of a rectifier smoothing circuit, an oscillation pin30 (R-Y) and pin31 (B-Y).
6. HORIZONTAL OUTPUT Pin25: Black A horizontal oscillation signal is output from pin37 of Pin26: IREF IC201 and switches the drive transistor Q431. This Pin27: Odd/Even output switching signal is current amplified by the drive Pin28: GND transformer T431 and drives the output transistor Q432. Pin29: - When Q432 becomes ON, an amplifying current flows Pin30: V-deflection stop output...
SERVICE CONTROL ADJUSTMENT B1 POWER SUPPLY ADJ. AFT ADJ. TU-AGC ADJ. MAIN BOARD HIGH VOLTAGE & H-WIDTH ADJ. FOCUS ADJ. V-CENTRE ADJ. V-SIZE ADJ. H-CENTRE ADJ. GREY SCALE ADJ. SIF BOARD SIF ADJ. CRT BOARD IC3811 IC3801 K38H2 K38H1 AUDIO BOARD IC1251 IC3451 IC3401...
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B1 POWER SUPPLY ADJUSTMENT HIGH VOLTAGE & WIDTH ADJUSTMENT 1. Set VR641 to be mechanically centre before [HIGH VOLTAGE ADJUSTMENT] pressing the mains ON/OFF switch. 1. Tune the receiver to the circular pattern. 2. Tune the receiver to a PAL circular pattern. 2.
CIRCUIT ALIGNMENT 10kΩ 0.002µF 75Ω 1kΩ Output probe Input probe VIF alignment SETTING Adjustment Waveform DC 15.5V C644 + By using T141, adjust "P" to AGC voltage (4.3-4.5V) IC201-pin48 be maximum amplitude. Output probe IC201-pin45 (Side b) Input probe IC201-pin7 Marker frequency 38.9MHz Sweep ATT...
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INITIALISATION (Important Notice) When you replace a memory IC (IC802), it is 2. Select the desired service item by using the Function necessary to initialise the IC as following step. button on the remote control handset. 3. Change the data by using the Level + or - button A.
CHASSIS ELECTRICAL PARTS LIST Product safety should be considered when a component replacement is made in any area of a receiver. Components indicated by a ! mark in this parts list and the circuit diagram show components whose value have special significance to product safety.
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Description Ref. No. Part No. Ref. No. Part No. Description IC1202 409 120 3401 IC LA7221 C141 403 028 4419 CERAMIC 56P J IC201 409 380 8703 IC TDA8361/N5 C142 403 068 0419 CERAMIC 0.1U Z IC271 409 404 0201 IC U3665M C143 403 027 1211 CERAMIC 5P J...
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Ref. No. Part No. Description Part No. Description Ref. No. C514 403 049 4204 ELECT 10U M R1006 401 038 5310 MT-GLAZE 39K JA 1/10W C600 403 076 4000 CERAMIC 4700P K 500V R1007 401 038 3712 MT-GLAZE 33K JA 1/10W R1008 401 027 6628 CARBON 75 JA...
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Description Ref. No. Part No. Ref. No. Part No. Description R1902 401 039 0413 MT-GLAZE 8.2K JA 1/10W R481 401 015 4738 CARBON 180K JA 1/4W R1902A 401 037 5014 MT-GLAZE 0.000 ZA 1/10W R482 401 027 2620 CARBON 5K6 JA 1/6W R1903 401 038 6416 MT-GLAZE...
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Ref. No. Part No. Description Part No. Description Ref. No. R842 401 020 2053 CARBON 4.7K JA 1/4W L1026 645 001 4550 PEAKING COIL 10UHK R843 401 037 5618 MT-GLAZE 10K JA 1/10W L1027 645 001 5656 PEAKING COIL 4.7UH K R844 401 038 5112 MT-GLAZE 3.9K JA 1/10W...
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Ref. No. Part No. Description Part No. Description Ref. No. -19-...
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Description Ref. No. Part No. Ref. No. Part No. Description -20-...
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2SA564(QA,RA), oppure 2SA1015(O,Y) specified on the part service manual and controls adjusted for normal picture. in posizione "OFF". Il voltaggio puo variare CE25B2-C-01 SERVICE REF.NO. sostituti esclusivamente con quelli indi- a meno che sia specificato altrimenti. be used for components replacement Waveforms were taken by using a wide con l'intensita del segnale.
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Main Board /Pannello Principal Circuit side/Lato del Circuito...