Samsung HLS4266W Picture freeze on CH 28

[rc6]

Re:

"Samsung HL-S4266W Picture freeze-up

by hainestkd » Fri Jan 01, 2010 7:12 pm



I was watching this TV and everything was fine until I changed channels. When I did change channels the picture locked up. I could not even change channels or turn the set off. After about 5 min. the set turned itself off and came back on with a picture for a couple of seconds than froze up again.



Next I unplugged the TV set and plugged it back in. It came on with picture and froze up again.

I noticed that a green light appeared on the front panel on/off manual switch that said "Lamp"



Do you think the lamp is bad or is it the color wheel? And how do you see the color wheel. Seems it is located in a pretty tight spot. Thanks in advance for the help or suggestions.”



________________________________________________________



My problem is similar to the above quoted entry of 2010.

My Samsung DLP locks up (but not every time) when I change the channel to 28-1 thru 28-4 (Los Angeles area). In the past, I have had success with using a power strip to cycle power and then rapidly pressing the down-channel button (or up-channel button if on 28-4) on the side of the TV. This would change the channel out of 28 and the TV would be unlocked and act normal. This action has worked for several years but I would like to solve/fix this problem (since this "fix" is presently not working now). Searching the web revealed Hainestkd (above) with a similar problem on the same TV model.



A main question would be:

Is there data information in each digital channel’s signal that the TV needs or uses to set up proper operation of the TV?

This only happens on channel 28, so is CH 28 data sometimes in error?

This would explain other channels working OK.

Otherwise, how is only CH 28 locking up the TV?



Trying “Mute (Menu), 1, 8, 2, Power” only turned the TV on. But this might not be a valid test because the screen stays dark and so cannot see any “results.”



Thanks,

rc6

[grayfox]

Hello!



I think the quoted problem might have been slightly different..



I think there is a problem with your DMD board, but I have no idea why it would freeze on that particular channel!



Now that "fix" work around sounds like a solid way to make the TV usable when it can be a number of reasons if a certain frequency cannot be displayed and maybe cause it to not respond..



Now it may be, in my opinion, that the "fix" might still be applicable and maybe the blank screen is only attributed to a new lamp...



When was the last time you replaced the lamp on this TV?



Hope I can help!

[rc6]

Hi Grayfox,



My similarities with “hainestkd’s” quoted problem just regards the first paragraph and two more sentences.



I suspect the problem would be with the DMD board also since it has to do with a particular channel frequency.



It would be nice to know if the TV could be manually “rebooted” to get itself out of being locked (like the reset button on a computer). If so, I could possibly solder in a couple of wires with a push button.



Is there any way to get a schematic of the DMD board? Or general explanation of operation? Is there any tech pub on this board? These would really help in understanding the circuit operation.



So asking again: Does the DLP TV require or need “data” from the digital broadcast signal?



Further problem operation description:

When the TV locks up, the screen sometimes (at the beginning) has a “freeze frame” of picture. After a short bit, it will go dark and recycle itself about every 50 seconds and give the “turn-on jingle.” At that point the TV flashes a quick, whitish “signal/picture” an inch or two at the top of the screen. It is at this time that rapid down (or up) channel button presses seem to work. There seems to be a short window of time that the DMD board is trying to “reset” or get new data. If the button pressing is at the proper moment, then the TV accepts the channel “data” and changes channel. If not, then it remains locked.

The TV only tries this “reset” for 3 or 4 times, then the TV turns off. At this time the remote will turn it back on but no further commands will operate since it is locked.

Or as said previously, cycle power with a power strip.



Present situation:

Tried the CH button pressing yesterday and it worked. Back with a working TV. Yaaaahhhhhh!!!!



So then I tried “Mute, 1, 8, 2, Power” and it came on with a menu defaulted to OPTIONS.

Entered (right arrow) that and then scrolled down to LAMP LIFE and noted 4,215 hours. I had changed the bulb out months ago. That is still “young” considering it is 2 bulbs. Next selected LAMP CLEAR, and now it is a zero hours.



What happens with a menu “Factory Reset” if pressed?



So for now the TV is working OK, just don’t go near CH 28.



Thanks for giving it a shot,

rc6

[grayfox]

Hello, ok I am sure someone on the board can get you the schematics...



As for your question, this would depend if you are using analog or digital inputs on your TV. The DMD will receive signal and required display arrangements either way, but they differ from an analog input (like a coaxial cable) because it had to be digitized in the DV board, while a digital input (say HDMI) will send the signal directly to the dmd board and might be susceptible to "interference" that might cause a glitch like the one you describe.. I do not see why not it is meant to process data into image, I just cant explain it!

[rc6]

Hi Grayfox,



My TV has an analog input (coax from a roof antenna). It has a very good HD picture with usually 8-bars of signal strength.



Since the analog signal needs to be digitized on the DV board, I would like to get that schematic also, if possible as well as the DMD board.



Will these schematics be in pdf form “attached” to this forum?



If so, great,

rc6

[grayfox]

Hello,



It has been a while but let me search my posts, a fellow board member shared a link to a site that is an online archive with free pdf downloads of all major DLP manufactures from Sony, Samsung, Mitsubishi etc. I will repost it here once I find it...



I have downloaded from the site before no pop ups or malware, its a safe tool to have handy I just lost it!