Question about Samsung PCH521R 52" Rear Projection Television

Open Question

HT problem, horiz. transistor with high current

I replace most of the components at the horizontal output, when I put out the LC circuit at collector of the output transistor, the high current disapear, but have small HT, if I put out the C asociates at colletor the HT are increased, but not good.
The Fly-back was replaced, the transistor was replaced, etc,etc,...
I have this projector working without all this components, but have problems in the left side of the screen, distorsions.

Erif Balut

Posted by on

4 Suggested Answers

  • 2296 Answers

SOURCE: Horz. Output Transformer for a GE Mod#46GW945

Check this guys: //http://www.electronica-usa.com/
This guys may carry that part: //http://www.globalsemi.com/search.aspx

Posted on Jan 24, 2008

  • 27 Answers

SOURCE: Horizontal Output transistor

IGBTs do not work well at high frequencies. They are not very linear, either. Even if it works, you'll likely wind up with a compressed and distorted picture.

Just put in an equivalent output transistor and call it a day.

Peace.

Marco

Posted on Feb 04, 2009

  • 4234 Answers

SOURCE: Replacing horizontal output transistor

Many times, the only problem is hte transistor itself. There is really no way to determine whether or not additiona parts are required until the known defective one is replaced. If there are other symptoms once the transistor is replaced, post them here and we'll guide you to the defective parts.

Dan

Posted on Feb 09, 2009

Slinteriors
  • 8617 Answers

SOURCE: Flashing power light

Check for these power supplies on the Sub deflection board first on the right side of the board there are two Connectors one is a 12 Pin connector CN803 From the top of the connector the wires should read;
30V
Gnd
Gnd
-30V
8.5 V
8.5 V
Gnd
Gnd
-8.5 V
Gnd
Gnd
13.5V
Next is the connector below that one which is a 10 pin connector CN802 they should read
11.7V
11.7V
N.C
Gnd
CTL
Gnd
34V
34V
Gnd
Gnd
Next is a 14 pin connector on the top left side of the board CN801 those should read
34V
34V
Gnd
Gnd
-8.5V
Gnd
8,5V
8.5V
Gnd
13.5
NC
12.5
12.5
Check those supplies and see if they are correct or if any are missing

Posted on Mar 09, 2009

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

A sansui tv switches on and off by itself. What could 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/
Desolder out the horizontal output transistor, and now power on the set. If the set now powers ON, replace the horizontal output transistor. It is faulty. [Collector to emitter or collector to base leak]

Jun 26, 2015 | Sansui Televison & Video

1 Answer

Onida igo 20 '' ctv t v 110 voltage one second


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/
Check the horizontal output transistor for collector to emitter leak.

Sep 18, 2014 | Televison & Video

1 Answer

No power sharp 21v-w70m


Short circuited component at its main board. 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 absent check the feeder resistor; if any. If you wish to get some details; check the site linked here. Viewing it in "Mosaic" will make surf easy. Surf the site with patience. Pull up older posts.
http://electronicshelponline.blogspot.com/
Give a special attention to its horizontal output transistor. Replace it, and check. Check this device for collector to base, or collector to emitter leak. Even a slightest leak, will cause sivere problem.

Apr 16, 2014 | Televison & Video

1 Answer

I have a dead tv make konka model kp2905qyt


Check the frequency of oscillation at the base of horizontal output transistor. It should be around 15.6KHz. If there is no frequency, the horizontal osciallator jungle IC should be suspected.

Nov 29, 2012 | Televison & Video

1 Answer

TruFlat Tv turns on then off


Hello
Check the supply rail to LOT. If LOT [Line Output Transformer] is fauty, it will take tremendous current from the SMPS power supply output, and the overload sensor circuit will be energiised and the supply to the whole system will sut OFF. That is happening eith your TV now. Just desolder out the horizontal output transistor, the transistor that drives the LOT, and switch the set ON, and see whether it stays on or not. If stays on, check the collector to emitor resistoance of the horizontal output transistor. If there is any short with it, replace it and switch ON the set for a short time, say 5 seconds or so, and check whther the replaced transistor gets overheated. If it overheats, make sure that the LOT said above has damaged, and must be replaced with same type and number. If the fault is with the horizontal out put transistor, the set will work normally after replacing it.
The components can be bought from local electronic spare part shops at your town. OK.

Oct 24, 2011 | RCA TruFlat 27F520T 27" TV

1 Answer

Audio and picture go dead red light blinks 7 times


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)

Jan 24, 2011 | Sony FD Trinitron KD-36XS955 36" TV

1 Answer

What is the problem if only retrace line appears on screen and without picture output? what circuit has a problem if b+ voltage increases up to 150vdc and it kills the horizontal output transistor...


1. Check the opto coupler in the SMPS circuit. Replace it with
new one. DO NOT SWITCH ON TV WITHOUT OPTO COUPLER.
This is feed back, to the switching transistor to control the oscillator.
2. Horizontal out put transistor going defective.

This is due the failure of diode near the EHT coil primary and
the transistor. The reverse leakage of the high voltage diode can not be
checked by the meter. Hence replace all the black coloured diodes
in the horizontal deflection circuit diodes with identical part no.
Horizontal out put TR will get over heated and will rupture. When you
replace with new transistor switch on TV and switch off immediately.
The heat sink should not get heated or warm up. This is the only way
you can protect the transistor when you replace other components one
by one.

After checking all the small components, finally EHT coil.



p

Aug 19, 2010 | Televison & Video

3 Answers

Pictures shrinks.. Panasonic TC-20LM Television


Shrinking picture is a voltage regulation problem in the switch mode power supply, Possibly a cap used in the feedback circuit. Or an over current condition on the B+. This is a very tech intense repair because there is no magic bullet. If it is shrinking on bright scenes then you can bet it is a regulation problem, bright scenes draw more current from the power supply causing this effect. I would not suspect the horiz output because the regulation for this circuit usually comes from the main switch mode power supply. One diagnostic is to monitor the B+ going to the horizontal output and see if it fluctuates. If so you can bet it is a cap or optical coupler in the switch mode circuit.

Oct 10, 2009 | Panasonic Televison & Video

1 Answer

Rear projection mitsubishi vs5042 no high voltage


Are you talking about the LV power supply or the HV power supply? The terminology your using is related to the horiz drive circuit. Have you checked the B+ off the regulator which should be about 120v or, it will on the pc bd for the correct voltage. Do you have sound? If you do then you will have to use use your scope to see if you have proper drive at the base of the Horizontal Output Transistor. Then we can go from there. Oh, by the way I can tell by the voltage readings you stated both of those transistors of turned off.

Feb 21, 2009 | Mitsubishi Televison & Video

1 Answer

Horz. Output Transformer for a GE Mod#46GW945


Check this guys: //http://www.electronica-usa.com/
This guys may carry that part: //http://www.globalsemi.com/search.aspx

Jan 24, 2008 | GE 46GW945 46" Rear Projection Television

Not finding what you are looking for?
Samsung PCH521R 52" Rear Projection Television Logo

Related Topics:

23 people viewed this question

Ask a Question

Usually answered in minutes!

Top Samsung Televison & Video Experts

The Knight
The Knight

Level 3 Expert

72256 Answers

Henry  Thomas
Henry Thomas

Level 3 Expert

1074 Answers

Jerry Greenberg
Jerry Greenberg

Level 3 Expert

1667 Answers

Are you a Samsung Televison and Video Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...