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Sony PVM-20M4U I have this Sony PVM-20M4U pro monitor which blew the horizontal output transistor Q501 (2SD1878). I've replaced it and it seems to be working ok...exept that the transistor is getting almost hot on the heatsink. I've checked the waveforms on the base and collector and they seem to look clost to what the service manual shows. My question is, do these transistor usually run that hot? Or is there supposedly something that's causing it to get that 'warm'? Bob

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These will run a bit hot, but make sure you have enough compound on it. If the old stuff was dry, use a solvent to remove it and replace the compound with plenty of new stuff.
Dan

Posted on Jun 06, 2008

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I ave sony 21 tv tube type power ok but no high voltage going to the tube.but te flyback is good what seems to be the problem?


Check and replace damaged component/s at its horizontal scan output section circuit. Check the LOT (Line Output Transformer) too for damage. Replace the horizontal scan output transistor. Check the input voltage to LOT. If the voltage is absent check the feeder resistor; if any. If you wish to get some details; check the site linked here. Surf the site with patience. Pull up older posts.
http://electronicshelponline.blogspot.com/

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Sony TV bought in 1998 it has no picture


Check and replace damaged part/s in its horizontal output section. Check the horizontal output transistor and transformer.

Jan 24, 2013 | Sony Standard (CRT) Televisions

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Will not come on. light blinks 6 times


Hello
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.

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When i turn on horizontal output tripping. B+ and low voltage ok


Hello
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.

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H out transistor defetive & number missing plz solve


Hello

The horizontal output transistor number for Sony KV-ES34M61

Horizontal output - [Q6807] == 2SC5480-01
Pin output - [Q6808] == 2SC5480-01 Again

Please replace bothe the transistor at the same time. Check horizontal output transformer [LOT of HOT], for any defects.. Ok

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1 Answer

Hi My toshiba CX36H60 has a problem -- no picture but sound is good. what could be the issue and how to rectify it. Please suggest.


As sound output is ok, main board is correct with respect to sound output, video IF and ther stages. The fault lies on the horizontal output section. It may be LOT fault. Check it further for horizontal oscillator stage, and horizontal output stage. Check the collector voltage at the horizontal driver transistor. If you have a frequency meter, check the frequency of that point. It should be somewhere near 15625Hz. If the frequency there is Ok, then proceed to horizontal output stage. Check the horizontal output transistor. If it seems to be faulty, replace it with similar type and number. If the replaced horizontal output transistor heats abnormally within seconds after swich on the set, surely LOT has troubel. Replace it also with same model mumber and type.

Oct 16, 2010 | Toshiba CX36H60 TV

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My 36xbr800 blinks six times then pauses then blinks six times, this is repeated......


Check the voltage input to horizontal output transformer [LOT]. Check the voltage at the collector point of the line drive transistor. If the line drive transformer primary gets open this type of fault mau occur. Also check the frequency ant the collector point of line drive transistor and the base point of line output transistor. It should be aroung 15625 Hz.
Check and replace the horizontal output transistor if needy. Replacing it is better. The horizontal output is not working or a short in secondary power supply of SMPS or lot secondary, is your problem

Oct 14, 2010 | Sony FD Trinitron WEGA KV-36XBR800 36" TV

2 Answers

My sony KV32 FX65B trinitron stopped working.. i took it to a technician and he said i needed to replace the FBT (fly back transformer) along with two transistors. I just replaced them and when i start...


When it is shifted to right vice versa, it indicates a distortion on the horizontal output. Try replacing all the capacitors around the horizontal output area with the same original value. Make sure the horizontal output transistors you replace hasn't started going gone bad already if you know how to check them. Them dimness in the picture is caused by the horizontal output not putting enough high voltage to the CRT. Look for leaking capacitors too. Also replace the resistors around the horizontal output, they may have burnt out or changed in value from overloading cause by the malfunction of the flyback, and the transistor.

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1 Answer

Sony 27s42 broke the horizontal output transistor


Be sure to make sure the connection on the horizontal driver transformer are soldered good. check caps around HOT

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1 Answer

1996 Sony 32" Trinitron - Suddenly lost picture and sound


The most common problem with TV was the failure of the Horizontal Output Transistor, this will also damage 2 transistors in the power supply and a resistor in the power supply also. (From memory): Horizontal Output location # Q501, 2 power supply transistors Locations Q601, Q602, and resistor Location R607. Also solder the Horizontal drive transformer, you can find it by following the circuit board from the base of the Horizontal output. Some models used an IC instead of the 2 transistors in the powersupply, it will have six legs and check like 2 transistors. Good Luck.

Jun 04, 2007 | Sony KV-32S26 32" TV

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