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Hello erl, hi.... the hissing noise is usually caused by high voltage arching, but this is suppose to be soft. if the hissing is unusually loud, the high voltage transformer clip cap may be loose, this may cause the horizontal line you see on the screen. take precaution when dealing with this.... here are steps that may help..
1. unplug the unit. allow around 5 minutes for all voltages inside the unit drops to a safe level. 2. open the back cover. place the monitor face down on a table with a dry clean rug or towel. 3. locate the picture tube. on the top side you will see a wire with a cap at the end. 4. use or wear a cloth glove and feel if the cap is loose. re clip the cap and make sure it is secured. 5. replace the back cover.
If the horizontal transistor getting shorted, this could happen. Check the transistor 2 SD1398. If found faulty replace it. But replace black colored doides in the circuit as a whole. Leaky diodes can not be determined easily with the multi meter. Especialy the small high voltage diode near the small transformer connected to the 2 SD1368 transistor.
TV is in high voltage shutdown protection mode. Check to see if Horizontal output transistor is shorted or open. If not then resolder all solder joints on HV transformer. If this does not fix it then you will need to do voltage checks off of H.O.T. and then possibly a bad HV transformer.
This usually is indicative of the EXTREMELY HIGH VOLTAGE anode connection somewhere between the flyback transformer and one or more of the crt picture tubes or the splitter. Being that this circuit has a running voltage potential of over 30,000 volts if you are not familiar with these YOU CAN BE KILLED messing with it!!! What happens is that there is a breakdown of insulation over time usually from dirt or other environmental contamination. Usually a good cleaning and replacing the HV anode wire that has failed. (hint) it will be the one that the "ticking noise" is coming from. The ticking noise is actually the high voltage arcing to the chassis/ground.
THAT MAKES SENSE, CHECK FOR HIGH VOLTAGE- YOU CAN SIMPLY HOLD A NY SMALL NEON BULB[LIKE THOSE USED IN PILOT AMPS] NEAR THE ANODE LEAD OR FLYBACK TRANSFORMER IF IT'S ACCESSABLE, AND IT SHOULD GLOW. THE NEXT STEP IS TO CHECK THE FILAMENT CIRCUIT FOR THE PROJECTION TUBES- OFTEN IN MODERN SETS, THE FILAMENT [HEATER]VOLTAGE IS OBTAINED WITH A COUPLE WINDINGS AROUND THHE FLYBACK. IF YOU HAVE HIGH VOLTAGEE, AND NO FILAMENT, A 'HACK' THAT WORKS IS TO USE A SMALL POWER TRANSFORMER [MOST FILAMENTS [HEATERS] ARE 6.3 VOLTS, BUT DOUBLE CHECK THAT- IF YOU HAPPEN TO HAVE ONE OF THE LESS COMMON LOW VOLTAGE HEATERS, AND YOU OVER-VOLTAGE IT, YOU'VE JUST DESTROYED A VERY EXPENSIVE TUBE.THE 2SD921 IS IN AL LIKEYHOOD THE HORIZONTAL OUTPUT, WHICH DRIVES THE HIGH VOLTAGE CIRCUIT. IF YOU HAVE A SCOPE, CHECK FOR APPROX 15KHZ SIGNAL AT THE EMMITTER OR BASE- BUT BE CAREFUL ABOUT THE GROUND LEAD- USE A 3 PRONG ADAPTER, AND DEFEAT THE EARTH GROUND OF THE SCOPE, OR YOU COULD DAMAGE THE TV'S POWER SUPPLY
This trouble symptom picture wide or"blooming", the picture becomes dim even with the brightness control full on,and there is an abnormal enlargement of picture or raster.Usually,the enlargement is uniform,but there may be some defocusing.In some circuits,the brightness control operatesin reverse(rotating the control for an increase in brightness produces a decrease) after reaching a critical point on the control. If the picture wide is not accompanied by insufficient width(a symptom of horizontal output failure) the probable cause is a high volatge circuit ony,particularly the HV rectifier and HV winding.Any circuit problem that reduces but does not completely eliminate the high-voltage output to the picture tube second anode can cause overscan. The most likely defects are leaking high-voltage capacitors,defective high voltge tube rectifiers,leaking high voltage leads,defects in high voltage circuit protective resistance,and shorted turns in high voltage winding of the flyback transformer.
You have a shutdown circuit. The shutdown circuit is working as it should by not allowing the TV to come on if it has a HV (high voltage) problem. This could be caused by a shorted HV Transistor in the Horizontal section or a defective IHVT (Integrated High Voltage Transformer). In any case you will have to get a qualified TV repair person to troubleshoot and repair this problem.
there is loose contact on the high voltage section in your tv.what you are going to do is open it,and reheat with soldering iron and a piece of soldering lead the video chroma section and the high voltage section,near the flyback
This looks like a problem with the High Voltage or switching power supply section of the TV set. What you need to do is to measure the voltage from the HV transformer to the Anodes of the CRTs with a high voltage probe, and check the voltage output of the switching power supply. What may have happened is a component may have shorted out causing an over-current condition with is triggering the shutdown circuit (These are the relays you are hearing). I would check the Horizontal Output transistor, and the components in that section of the TV.
In addition check the voltage test points on the HV / Horizontal and switching power supply board. This will determine if the section is working or not (most likely not). Make sure you have a schematic, and multimeter and a high voltage probe.
I hope this helps, Thank you, Shuttle83