Dicas Reparação

Modelo - Chassis

Pesquisa: Enviar Dica Resolvida
Resultados 77937
Pedir dica reparação
PICTURE DISTORTION Vertical flutter at top one-half inch of picture, increasingvertical size control would eliminate this and fill out picture, butretrace lines would appear. Vertical output waveform at Pin 3 of IC502was of sufficient amplitude, but had horizontal signal
CHANNELS NO LOCK No reception for 30 minutes when set is started from a coldstart. Then channel change was very slow. Channel did not changeinstantly but slowly over a period of 5 to 10 seconds.
PICTURE DISTORTION Piecrusting in picture.
NO PICTURE No picture, distorted sound. Found VHF to be very snowy.
REMOTE ONLY WITHIN 10 INCHES, REPLACED Q2 "N" BOARD Remote had to be within 10 inches of TV unit to activatevarious modes. Found Q-2 amp on N board with base emitter leakage.
INTERMITTENT RETRACE LINES IN PICTURE, REPLACED R722 After the unit was energized, fine retrace lines wouldappear after 5 seconds and there was no control of brightness. G2voltage would not go low enough and G1 voltage was 125V DC instead of 30VDC. Wrong value resistor had been inserted in board (R722) i
INCORRECT TUNING OPERATION, REPLACED R078 In program mode, pressing tune-up button would cause a changein address position only and could not program any channels. Also, nochannels could be put into or removed from memory.
DEAD DC block assy failure (distorted waveform) DC fuses open.
DEAD, REPLACED MICA SPACER UNDER VERT OUTPUT TRANSISTOR 2.5 amp fuse on B+ line would blow every 7 to 10 days.Replacement of the fuse restored operation and hours of testing providedno clue to problem causing fuse to open. By by-passing the relay witha jumper and using a variac, increasing AC input to 130V A
SNOW PICTURE, REPLACED BT981 PRESCALER Unit goes to snow. Substituting tuner didn't cure problem.Voltages around front end seems to be at spec. Tried prescaler andthat solves the problem.
POOR REMOTE OPERATION, REPLACED Q1 Remote would operate intermittently and is usable up to6 feet from cabinet. Q1 on head amp board noisy - collector voltage onQ017 on MD board was varying between 4 and 8 volts.
SNOW PICTURE, REPLACE C209 Snowy picture on all channels. Uncontrollable RF, AGC:measuring DC potential at Pin 5 of IC201 (CX555) netted approx. 2.5VDCwith no change upon varying RF AGC potentiometers. Measuring C209 outof circuit yielded approx. 20 microamperes leakage.
INCORRECT TUNING OPERATION, REPLACED ZENER D008, Q006, Q008 Unable to tune any VHF/UHF stations.
POOR REMOTE OPERATION, REPLACED C4 The range of the remote control was no more than about8 feet. There was excessive noise seen at output of N board, remoteamplifier.
DEAD Came dead with shorted horizontal output and fuse. Replaceparts, plug to variac and slowly raised line voltage. Current wasexcessive showing short on the circuit, but doesn't show on the ohmmeter.Found bad flyback.

Assistência TécnicaAs dicas apresentadas destinam-se a técnicos de eletrónica, a tentativa de reparação ou assistência sem ter conhecimentos de eletricidade e eletrónica, podem provocar danos mais graves aos equipamentos e, devido a tensões muito elevadas em alguns circuitos, graves danos fisicos que podem constituir um risco em determinadas reparações.

Não arrisque reparar equipamentos com tensões elevadas se não tiver conhecimentos técnicos para o fazer em segurança.

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