The Hor Output transistor is connected to the Line Output Transformer. This transfromer provides a lot of voltages around your TV set but includes the very high voltage to the Picture tube...
These transformers are specially tuned to resonate at a certain frequency,
The Hor output transistor needs to match this frequency....so if the wiring inside the transformer is shorted by "just a bit" the picture will be visible but the transistor is struggling to match the transformer impedance,from the mismatched tuning...so the transistor draws more current from the power supply.. runs hot then burns out...
Usually manufacturers provide a Trip circuit that detects that an overload on the power supply is occuring and cuts the power to the Line output stage ...this is usually detected by a clicking sound within the power supply its called hiccuping.
If some one has altered the correct setting on the power trip circuit then the next thing that happens is the Transistor goes Blooooey like in your case.....
So to save you a lot of money replacing the output transistor
please replace the output transfromer as well next time...
But please... please... re-check the power supply trip circuit to save you a lot more expense in the future....
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Check the LOT and Horizontal Output Transistor. If horizontal output transistor get shorted [collector to emitter or collector to base], this kind of fault will occur. Here there is nocollector to emitter short as B+ is ok. Check for collector to base leak. It is best to repalce the horizontal transistor with a new one, and switch on the Tv for a short while, say 10 seconds or so, and feel the heat of the replaced transistor. If it gets overheated, of LOT makes a whisiling of hissing sound, LOT is faulty, and shoul be replaced sith same type and number. OK.
6 blinks = No Horizontal (H STOP), no raster, goes to the blinking self diagnosis function immediately. Check C515 & 516 and the jungle IC, IC206 (or similar component references for your model) and replace flyback transformer if required.
Generally, whenever horizontal OCP (over current protection) occurs, the primary cause is usually the flyback transformer (these short circuit/burn out), the horizontal output transistor(s) and the tuning capacitors in the transistor(s) collector circuit must all be replaced together. It is also a good idea to check the ABL (or beam limiter) circuit as components may have been compromised in it due to the failing flyback.
You could take it to a service centre and obtain a quote for estimated repair costs, then you can decide afterwards if it is worth repairing or not. It may not be economical and/or expensive.
A protection circuit has cut in - possibly due to a fault in the line output stage (flyback transformer could be short-circuit and horizontal output transistor could also be shorted).
Assuming the power supply/HT rail is all OK, replace the above parts, touch up any suspect solder joints, check and replace any capacitors (electrolytic and the tuning caps in the collector of the horizontal transistor - always replace these caps (rated at around 2kV - 6kV) whenever you replace the flyback)
I disagree with given info, this tv has no horizontal output transistor because it is dlp tv. 3 red light blink means lamp cover is not placed back properly after lamp replacement/ lamp checking. Make sure lamp cover is fixed back in its place securely and tight.
whenever fuse blows every time it is the indication of short circuit in tv.
so please do not put fuse unless you know the cause of blowing fuse.
these are the reasons of blowing fuse.
1 main filter cap.short.
2 rectifier diode short.
3 swithing transistor short
4 horizontal output transistor short
5 caps & diodes connected to flyback transformer short.
6 print short.
7 at last if every thing ok then flyback transformer defective.
hope this will help.
if you are not a tech person call skilled tech to fix it.
The F27442 uses the CTC203 series chassis and that symptom is very common. If the horizontal output is shorted you MUST resolder the coil in series with the base of that transistor and the pins of the small horizontal drive transformer. When they have been properly resoldered you can put in a new original horizontal output transistor. If the output transistor shorts out again then your flyback (high voltage) transformer is shorted and needs to be replaced.
The horizontal output transitor is always connected to the primary winding of the flyback transformer (via collector) and also to the horizontal deflection coil via an electrolytic capacitor.
The most likely suspect for damaging the transistor is the fylback transformer. In some countries there are electronic stores that test flyback transformer by winding a few turns on the ferrite core and applying a test voltage. This test will only test the secondary.
The primary winding is difficult to test for turn to turn short because the resistance is quite low and you do not know the 'good' resistance.