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Eric
Eric, Technician
Category: TV
Satisfied Customers: 1090
Experience:  TV Repairman for over 30 years, still working in the field
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I have a Samsung SP54T9 HEX Rear Projection TV. I had issues

Customer Question

Hi, I have a Samsung SP54T9 HEX Rear Projection TV. I had issues with convergence, i replaced the STK392-010 ICs and couple of burned 3.9 Ohms resistor. After powering on the STK's were overheating and the TV shutdown itself.The front red light blinks continuously.
Submitted: 1 year ago.
Category: TV
Customer: replied 1 year ago.
1. I replaced the STK392-010 ICs.
2. Replaced 3.9 Ohms resistors (RZ144, 145)
3. Replaced HOTCurrent Situation:
When i power on, it gives a whisking noise, as if it is going to start and a gun get low power light inside. The red led blinks continuously
Expert:  Dimmu TV replied 1 year ago.
Hello my name is***** look forward to assisting and am very sorry to hear that you are having this problem. I want to warn you that it is possible you will need to replace a part in order to fix this. There are a few different things that can cause this and a couple different parts so we would need to troubleshoot to find out for sure. The red light should blink in a pattern but it may be a long one. It will have short breaks in between, what is that pattern?
.
Customer: replied 1 year ago.
Hi Fred,It blinks continuously, means on and off continuously. Also when i power on, it sound as if it is going to start, the tube makes a slight hissing noise and just stays stays like a 0 watt lamp. I can change parts, no issues.
Customer: replied 1 year ago.
Picture of Power Deflection Board
Expert:  Dimmu TV replied 1 year ago.
It may be me but that looks extremely dirty, have you cleaned it already? Using compressed air even canned air duster would work. Dust can cause these components to heat up very quickly. Dust can also cause the hissing you are hearing.
.
Customer: replied 1 year ago.
I cleaned it using high pressure blower. This picture was taken after I removed the back cover. The hissing is not continuous, what i mean is when you turn on a CRT TV it will give a initial one time hissing noise of powering the tube.
Customer: replied 1 year ago.
after that noise, the base of the tube will glow like a 0 watt bulb / like a value transistor.
Expert:  Dimmu TV replied 1 year ago.
Ok I thought you meant the hissing stayed on. Have you checked the caps yet? There is a large connector on top of the back of the CRT usually with a thick Red wire attached that could cause this. It should be the anode cap. Here is a picture of one:
http://www.electronicrepairguide.com/images/fitintotube.jpg
.
Customer: replied 1 year ago.
Its a CRT projection TV, it has voltage divider which connects to the flyback transformer.
Expert:  Dimmu TV replied 1 year ago.
You should still have a anode cap for the tube. I apologize but I need to opt out and open this to all experts.
.
Customer: replied 1 year ago.
Ok. No Problem. I will post more picture to provide exact visuals.
Customer: replied 1 year ago.
After I power on, its gives a whisks sound and all the tube stays with a mild light. Refer the attached picture.
Customer: replied 1 year ago.
More pictures of the tube
Customer: replied 1 year ago.
Hi, any updates or ways to fix ? :-)
Customer: replied 1 year ago.
Hi... I am waiting to get an answer or suggestions for past 1 week, Can a technician be assigned for my question and issue ?
Expert:  Eric replied 1 year ago.

Hi my name is***** tech for 30 years

Expert:  Eric replied 1 year ago.

When you are online post and I should be able to answer within a few minutes

Customer: replied 1 year ago.
Hi Eric,Hi, I have a Samsung SP54T9 HEX Rear Projection TV. I had issues with convergence, i replaced the STK392-010 ICs and couple of burned 3.9 Ohms resistor. After powering on the STK's were overheating and the TV shutdown itself.The front red light blinks continuously.1. I replaced the STK392-010 ICs.
2. Replaced 3.9 Ohms resistors (RZ144, 145)
3. Replaced HOTCurrent Situation:
When i power on, it gives a whisking noise, as if it is going to start and a gun get low power light inside. The red led blinks continuously.
Expert:  Eric replied 1 year ago.
OK we are now on post chat
my experience with these sets is that either the new STK are shorted due to you not using heat sink compound and soldering pins together. (I've done this)
also the resistor values sounds wrong do you have the schematic?
I offered a phone chat if that is easier
Customer: replied 1 year ago.
i did replaced the resistors as per the value in the parts catalog. I checked the shorts between each pins of the STK and found no short, also applied a thin layer a heat sink compound.When i power on one STK heats a lot and other is dead cool. The CRT doesn't light up, but it gets a mild light at its end. I attached the picture of that in my previous chat.
Customer: replied 1 year ago.
By the way, I am from India. Let me know your official number, so i can call you back.
Expert:  Eric replied 1 year ago.
the phone or skype chat is an extra fee, did you want to do that?
Customer: replied 1 year ago.
We can try chat, if not working then will try skype
Expert:  Eric replied 1 year ago.

Common sense on this one is that the TV was working before you replaced the STKs, pull the convergence winding plugs and see if the TV comes on, or open up the supply resistor to the ICs (removing the positive and negative voltages) from the ICs. The tv should come on with bad convergence indicating that the convergence ICs are somehow loading down the set into shutting down, try this and report please

Expert:  Eric replied 1 year ago.

what i mean by pull the windings is unplug the three convergence plugs , not the main yoke plugs

Customer: replied 1 year ago.
I removed all three convergence plugs. Attached the pic of plugs which i removed, marked in red box. Same result, even after removing.
Expert:  Eric replied 1 year ago.

Ok it was something to try, some will power on even with these plugs disconnected.

some won't are the ICs still getting hot?

can you measure voltages?

Customer: replied 1 year ago.
The ICs are not getting hot. Both are cold. Yes, i can measure the voltage.
Expert:  Eric replied 1 year ago.

Ok on the ICs what do you have on pin 11, 12, 13, 14 and 18?

with everything plugged in

oops and pin 17 too

Customer: replied 1 year ago.
Ok, You mean voltage between these pins ? Am i right ?
Expert:  Eric replied 1 year ago.

no ground the black lead, set to DC voltage and measure the pins with the red lead of the voltmeter.

also tell me how many fuses you see , they are usually green shiny and look like resistors surrounding area of the ICs?

Customer: replied 1 year ago.
There are no fuses around the ICs, i can see the green color pico fuses in some other place. One STK is getting hot, and other one is cold. I read the voltage reading in the cold STK IC. the value is below.Pin 11 = 24V
Pin 12= -24V
Pin 13= -24V
Pin 14= 24V
Pin 17= -24V
Pin 18= 24VI am unable to read the voltage of other IC, as it is inside. Marked the cold and hot ICs in the attached picture.
Expert:  Eric replied 1 year ago.

The hot one may be shorted,

one way to tell is swap the ICs and see if it gets hot in the other spot (alot of work)

I can not find a schematic for this model, but even without it. if you are getting those supply voltages

the fuses are probably OK.

Customer: replied 1 year ago.
Ok. Can i replace hot STK with a new one and see if it still gets hot. I have the schematic diag in my other laptop, unfortunately hard disk crashed and recovering my files from it. will try to send the schematic diag pdf tomorrow, if not i will download it from nodevice.com portal.
Expert:  Eric replied 1 year ago.

Ok lets do that I will check in around 11am or so, thx

Customer: replied 1 year ago.
Hi Eric,4I apologize for the delay. I replaced the STK which was turning hot with a new one. I found the same problem again, the new one also turning hot. I am attaching a short video of how it power on. It may be useful to you. By the way, i got the schematic files, there are 7 files, let me know which file you require.
Customer: replied 1 year ago.
Customer: replied 1 year ago.
PCB Diag
Customer: replied 1 year ago.
Hi Eric, any update post viewing the video clip ?
Expert:  Eric replied 1 year ago.

A diagram of the voltages for the power and convergence circuits might help.

I may not check back today, but upload what you have, Thx

Customer: replied 1 year ago.
Hi Eric,Apologize for the delay.I removed both the STK ICs. Now I am able to get a video, but only half screen. Attached is the picture of how it display's the video.
Customer: replied 1 year ago.
Picture
Customer: replied 1 year ago.
Hi Eric, Any luck ?