Mulja tv repair portal
Equipment Repairs => CRT TV forum => Topic started by: markc on December 04, 2008,10:17:27
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I still have not resolved the problem with this set, which will not come on, it does try, but reverts back to standby. So far I have replaced both convergence IC's, frame IC & the line output tramsistor which blew for no apparent reason. I have had the PSU running on a dummy load and all voltages are OK. But when switched on the red LED flshes 4 times then stays on permanmently.(Back to standby) There is occasionally a chirp from the PSU as it tries to start. I am considering trying the LOPTX next, but would value any other suggestions as this is getting expensive.
Thanks in advance.
Mark
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Never replaced a LOPTx in a Samsung, always the first I guess.
Check D402, C407 & C408 on screen volts.
Could try disconnecting HT, splitter, 200v from tube etc, see if something is loading down LOPT
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we are samsung dealers and as bc109 points out lopt failure is rare, in hundreds we have replaced one, our uk versions are SP42w4, if the conv ic,s have failed the fuses, soldered in line under the conv ic.s always point you in the right direction, if his is the version, w4, the convergence panel is separate and can be unplugged. these sets have separate eht and line output stages, are you clear on this?
the crt heaters are supplied by the line stage, do they come on briefly, also the rgb output stage ic,s can go s\c, esp after a crt flashover, unplug all three feeds to the crt to prove this area is ok, the socket is right at the front of the set, about 6 pins, this removes the 200v and 12v to the crt panels, and also the crt heaters.
do you hear the eht start up briefly, the line ouput must be established before the eht kicks in, one last point, and im asking bc109 this as well, have you had scan coils s\c?
if you remove them they are heavily corroded, caused by coolant leakage and running down inside the coils
in serious cases this can also fall on the the middle pcb severely corrodong the area towards the front of the set, later models fitted a drip tray to flow away the coolant to an area of the set where no damage is done,(the bottom of the cabinet) brilliant bodge i thought
good luck
tony walker
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Yes I've seen corroded parts all over the place in Samsungs.
I should of asked before, what chassis is this J60A?
In the J54A the ProScan module fails, resulting in various symptoms. No start, starts then back to standby & vertical problems. Not sure about the J60A not starting if no vertical?