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 its horizontal output stage circuit for any short. Check the horizontal output transistor, for collector to emitter, of collector to base, leak. Replace it with a new one and check whether the newly replaced transistor gets too hot. If so, suspect the FBT. To get some details, http://electronicshelponline.blogspot.com/ Pull up older posts.
Six blinks denotes the absense of horizontal sweep. Check the horizontal output transistor, whcih can be located very near to the LOT [Line Output Transformer]; for short. If it is shorted, LOT must be suspected. Replace the line output transistor with a new one, and switch ON the tv for a short period of time, say 6 seconds or so, and check the heat of the replaced transistor. If it overheats within this time, be sure that LOT is damaged; shorted inside; and should be replaced with same type and number. If a digital multimeter which can measure frequency is available, take the frequency at the collector of the horizontal driver transistor. It should come around 15525Hz. If not replace the jungle IC. 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.
ur tv has problemwith horizontal output stage. check the horizontal output transistor. if it found short replace the same and switch on the tv. if the same fault occur again, then the lot (line output transformer) may be faulty. also check for any dry soldering in the power supply stage and horizontal output sage.
ALL the next is with the tv unplugged (NO NO power)
resold the jungle (video processor) all around
following the horizontal drive pulse path and arriving to the horizontal area just after the horizontal transformer and in the base of the horizontal DRIVER there is a electrolytic capacitor (if this chassis uses this one,) Change it (maybe is dry)
solder all components i just told you in the last step. horizontal driver, transformer, etc
if a transistor is blowing with no reason (there is a reason: the collector receives 130 volts but cannot hold it forever, It has to be in some place. if the switching pulse doesn't arrive to it the transistor throws this 130 volts and burning itself. i hope it is help full.
It sounds like the high voltage circuit got damp and arced. This arc caused the horizontal output transistor to short.
You might try replacing the output transistor if you're experienced in this type of repair. If not then you need to take it to a repair shop.
The "whistle " you're hearing is the power supply indicating that it has a short on its load. When the power supply has an over load (short) its frequency drops down when your ear can hear it oscillating. This type of power supply is a switching power supply normally operating a several thousand hz(cycles) which is out of range of human hearing.
TDA 8362B IC which have vertical freq.output is at pin no.43. (vert.osc)
for fixing this problem minimise brightness to avoid crt burn.
proceed as follows
1 if you are getting sawtooth at output of ic tda 8362 pin 43 then check
1 supply at vertical output ic from eht.
2 yoke connector loose .
3 check vertical output ic parts.
4 finally vertical ic.
please check for normal output from power supply even though fault gets rectified just for protection.
most high pitch noise comes from the anode conection on the picture tube thats connected to the flyback anode cap thats mean there is a high voltage leak,to stop the noise you can discharge the high voltage take off the cap and clean with alcohol.if the noise continue.you will have to put some red or clear silicone both the cap and tube stick together leave to dry for about 2 to 4 hrs.this will eliminate the leaking.good luck.