Samsung DTB-H260F HDTV Tuner

[oyabak]

Re: Samsung DTB-H260F HDTV Tuner

it's alive!!! thanks to this thread!!!

[sjlorenz49]

Re: Samsung DTB-H260F HDTV Tuner

I also had a similar issues this past week, although I did not see my blue light come on for a fraction of a second. I ordered the capacitors online and they came today. I had not done any soldering for over 20 years. But I followed the thread (pictures were great) and put in the new 1000uf 10v capacitor. It took me less than 10 minutes and I took my time doing it. It returned to life like the others.

Many thanks to this forum! It is a wealth of information.

[justneed2no]

Re: Samsung DTB-H260F HDTV Tuner

Thanks bluto for starting this string !! Came back home from the holiday to find my "Blue Light" going out. Went online and googled "Samsung DTB H260F", opened the sucker to find, no swollen 1000mf, no Samxon (brown not green caps). Decieded to try and replace the caps anyway. Ordered the caps from Digi-Key,$4.00 and 30 minutes later It's up and running. One more to add to the list THANKS AGAIN!!

[arupert]

Re: Samsung DTB-H260F HDTV Tuner

Just wanted to report another DTB-H260F fixed thanks to this forum. Mine had the 8 seconds then power LED off problem. I could not see any bulging caps, but I replaced the two 1000 uf caps as described in this thread and now its working again. We use the DTB as a second turner for recording. I almost threw it out - so glad I found this forum when I was looking for a schematic.

I had a similar problem a couple of years ago with a Samsung 214T LED flat panel display - after replacing bad capacitors, it has worked perfectly ever since.

Many thanks!

[bluto]

Re: Samsung DTB-H260F HDTV Tuner

I'm thrilled to see that folks are still finding this thread and fixing their boxes over three years on. Happy New Year!

[teamfx]

Re: Samsung DTB-H260F HDTV Tuner

Hi guys, I replaced all capacitors mentioned here, however, the problem with my unit has not resolved. The unit turns itself on automatically. Also, I figured that the problem is with the big green board and not the brown one where I replaced capacitors. There is no visible anomaly on the green board. Does anyone know how to fix it please!

I'm pretty sure my DTB is suffering the same issue. Though, I found something unique in my troubleshooting so far... I've had the Samsung for 6 years now and the brown board still appears to be operating normally; the LED light remains lit after 8 seconds and there's no sign of any physical damage. I did notice the dead air on my monitor screen that shows no picture nor sound.

It attempts to power on, but remains pitch black with occasional scrambled artifacts before going dark again. The power board seems to be unaffected from this abnormality. I wonder if that could be another side effect of overheating... I hope it's not permanent.

[ben7]

Re: Samsung DTB-H260F HDTV Tuner

I'm pretty sure my DTB is suffering the same issue. Though, I found something unique in my troubleshooting so far... I've had the Samsung for 6 years now and the brown board still appears to be operating normally; the LED light remains lit after 8 seconds and there's no sign of any physical damage. I did notice the dead air on my monitor screen that shows no picture nor sound.

It attempts to power on, but remains pitch black with occasional scrambled artifacts before going dark again. The power board seems to be unaffected from this abnormality. I wonder if that could be another side effect of overheating... I hope it's not permanent.

Could be a failed voltage regulator, or a failed solder joint or two on the mainboard

[teamfx]

Re: Samsung DTB-H260F HDTV Tuner

Hmm... That's a possibility. Any idea where the voltage regulator might be located exactly? Here's a picture of the patient, just in case. Sorry for the quality, but yeah.

[ausheaven]

Re: Samsung DTB-H260F HDTV Tuner

Is it time for the world to Start boycotting Samsung products.
Bad caps bad caps, problem problem everywheres for their products.
Monitor, TV, HD Set-top, the list goes on.
Don't trust them with their 3 year replacement warranty, because the moment it is out of warranty, guarantee that it will breakdown and you have no recourse because they knowingly uses inferior components and they get way with it.
Look around your neighbourhood the next time there is verge collection and count the number of Samsung branded products being disposed off.

Best of luck to all the unfortunate people.

[salongaopm]

Re: Samsung DTB-H260F HDTV Tuner

my dtb-h260f is not responding to remote control. i am using a new remote control. the tv is showing "scrambled or weak signal " message using hdmi. nothing when using analog rca cables. still not working even after i replaced the following caps:
82mfd 450v (1)
1000 mfd 10v (2) (kmf)
470 mfd 10v (2) (samxon brand)
47 mfd 16v (1)
all the caps doesn't have any sign that they are bad.
any help will be greatly appreciated.

thanks!

[bop12]

Re: Samsung DTB-H260F HDTV Tuner

Didn't work on my LN32A550. Samsung sent the repair guy and he replaced the board. No GO. Looked at it after he left and all Caps seem OK on the power board. Set when plugged in flashes the led as it is turning on. Sometimes the back-light comes on. Sometimes the LED stops flashing and I get a green raster like pattern then goes back to no back-light and the flashing LED. Pushing buttons, CHN, Vol, Source doesn't seem to help. Thought it could be a cracked board or bad solder joint pulled the boards and inspected them under magnification, nothing.
Couldn't find any of the caps looking bad. I tried freeze spray with no success. Once after 10 minutes of this nonsense it actual showed a normal screen, but that went away in about a minute. It is back to having a mind of its own.

[CyberKnight]

Re: Samsung DTB-H260F HDTV Tuner

Replaced both of the 1000uF @ 10V Samxon caps and the H260F is working fine again. Thanks for the excellent info and heads-up about these crappy caps. And I agree with bluto that it would have been nice if we could have paid an extra $5 and had good caps from the start!

Best,

[mike flood]

Re: Samsung DTB-H260F HDTV Tuner

The voltage rating of the capacitor is the maximum allowed voltage that the capacitor can tolerate. Think of the voltage as electrical 'pressure'. The higher the voltage, the higher the pressure. So when a 10v capacitor is used, the circuit that it is in should be no more than 10 volts. Substituting a 16v capacitor in will not change the voltage supplied by the circuit. Think of it as if you were substituting in a pipe the same diameter, but could withstand a higher pressure. Using the original amount of pressure in this hypothetical new pipe would make no difference. I hope that makes sense.

Theory (THAT I HEARD) says that a cap rated at a higher voltage than the circuit in which it is used will become maxed at that voltage. This says that if you later try to use the cap at it's rated voltage it will fail. I have not seen a case of this and so cannot say if this theory is fact or BS.
No harm is done to use a high voltage rating cap in a lower voltage operation.

Yes. . .it IS a weird world. Grin.

[bishoptf]

Re: Samsung DTB-H260F HDTV Tuner

I dont have a h260 but I do have a t151, which I assume was an earlier generation tuner. I pulled it out to put it back into service and turned it off and when I tried to turn it back on, the power light flashes for a period of time and just goes back out.

However mine appears to have a bunch more capicators then the h260 does. I went ahead and ordered a bunch of the ones I needed from digikey, used the panasonic FC types.

I plan to post a picture later, but looking at them its not apparent which ones I should start with, although some do appear to be slightly bulging.

Will try to post a picture of the power supply board later. Thanks.

[bishoptf]

Re: Samsung DTB-H260F HDTV Tuner

Here are the pics of the board:









Let me know, I think the large one is bulging and some of the smaller ones appear to be also..

[bishoptf]

Re: Samsung DTB-H260F HDTV Tuner

One more question I have a couple of 2200mf 10v capacitors, samsung I think but what I am scratching my head is that one of them is larger then the other one but the rating from what I can read appear to be the same.

Anyone explain this?

[bishoptf]

Re: Samsung DTB-H260F HDTV Tuner

Well I replaced all of the caps, I missed one appears that there is a 50v one that I need to replace along with a 60V one also but no joy, still exhibits the same sympton. Flashing power led and a tick tick tick with the light. If I remove the 22mf 50v cap the flashing goes away so maybe its that cap or close to it.

Anyone have any other suggestions on what to look at to replace?

[bluto]

Re: Samsung DTB-H260F HDTV Tuner

The ticking indicates that something in shorted and the power supply is shutting down automatically (protection mode). I don't know how to tell you to troubleshoot it other than to see if you can figure out if it is the power supply that is shorted or if it is the actual tuner mainboard that is shorted. You would have to figure out which pins on the big white connect make the power supply turn on and trick in into doing so.

The other approach that I would take is to scrutinize the regulators (attached to the heatsinks) and the diodes to look for any signs of distress. Beyond that you would probably have to remove those components individually and test to see if they are shorted out.

But that's just my non-expert approach. Someone else might have a better idea.

[bishoptf]

Re: Samsung DTB-H260F HDTV Tuner

The ticking indicates that something in shorted and the power supply is shutting down automatically (protection mode). I don't know how to tell you to troubleshoot it other than to see if you can figure out if it is the power supply that is shorted or if it is the actual tuner mainboard that is shorted. You would have to figure out which pins on the big white connect make the power supply turn on and trick in into doing so.

The other approach that I would take is to scrutinize the regulators (attached to the heatsinks) and the diodes to look for any signs of distress. Beyond that you would probably have to remove those components individually and test to see if they are shorted out.

But that's just my non-expert approach. Someone else might have a better idea.

Thanks, i think I have figured it out, wish that I would have found a thread earlier but the ticking sound stopped when I removed the 5v cap, didn't have one to replace it with. That one is up close to one of the heatsinks and it appears that its an IC that is bad, part number KA1M0565R, fairchild Power switch.

I found a thread that talked about these going bad. It appears to be out of production and I couldn't order from digikey or mouser but found them on ebay so I ordered one up. It was ind of a pain to remove although I am a noob at doing these so not sure what the best removeal method.

I probably didn't need to replace all my caps but oh well. Here is the datasheet for the part - http://pdf.datasheetcatalog.com/data.../KA1M0565R.pdf

Not sure what I could have substituted in the place for this, let me know what you think.

[bishoptf]

Re: Samsung DTB-H260F HDTV Tuner

Question, hopefully bluto or someone can chime in. I ordered a part last night although it appears that I should be ordereing the formed part and the one I ordered was not. I assume I can try to bend the leads carefully and get it to work, is that possible and does anyone have any tips for doing such.

This looks like tha part number I am after - KA1M0565R-YDTU

Looks like I can get them on ebay from china, but not sure i trust them.

Thanks.