Announcement

Collapse
No announcement yet.

User Profile

Collapse

Profile Sidebar

Collapse
Avatar
2many
Member
Last Activity: 10-03-2018, 06:18 PM
Joined: 07-29-2016
Location: NYC
  •  
  • Filter
  • Time
  • Show
  • Source
Clear All
new posts
  • 2many
    replied to Help with Toshiba 50L2300U
    in Troubleshooting TVs and Video Sources
    Re: Help with Toshiba 50L2300U

    Been a while since I started this thread looking for help. My Toshiba is still working well after I fixed it and turned down the brightness.

    As I recall, after removing the screws, the bezel has to be pryed off. It is held on with clips and there are many. Once you get one clip pryed loose, stick a piece of cardboard in there so it cannot pop back in. Look on youtube on how to take apart any LED TV. They all snap together the same way I believe.
    See more | Go to post

    Leave a comment:

  • 2many
    replied to Hannspree T280H RGBW screens and no response from remote when hot
    in Troubleshooting TVs and Video Sources
    Re: Hannspree T280H RGBW screens and no response from remote when hot

    It's hard to access the main and PS board since they are both mounted in a metal enclosure. Cutting away the top and bottom of the enclosure to get more air flow was not enough to stop it from cutting out when it gets hot (less than 30 min). When running without the metal enclosure, it does not cut out. The enclosure is needed to mount the boards, can't just toss it. I ended up cutting 2 big openings on the back of the enclosure with tin snips. The masking tape covers up the sharp edges which was too much work...
    See more | Go to post

    Leave a comment:

  • 2many
    started a topic Hannspree T280H RGBW screens and no response from remote when hot
    in Troubleshooting TVs and Video Sources

    Hannspree T280H RGBW screens and no response from remote when hot

    I was lucky and just fixed my 50" Toshiba with just an ohmmeter, no schematics. I replaced 2 Schottky diodes and 1 Mosfet that was shorted on the PS board and that fixed it. I don't think I'll be as lucky on this Hannspree T290H. When the set is on for approx 1/2 hour or more, the set cuts out. How long it takes is dependent on how hot the weather is, hotter the day faster the problem occurs. In the winter months, it does not occur.

    The problem is as the set gets to a certain temperature, video and sound stops, the screen would cycle between red, blue, green, white at approx...
    See more | Go to post
    Last edited by 2many; 08-08-2016, 07:42 AM.
  • 2many
    replied to Good video on LED TV disassembly?
    in Troubleshooting TVs and Video Sources
    Re: Good video on LED TV disassembly?



    That's a good one on LED replacemnt, I am looking for one one showing technique and special tools used taking the bezel and back cover off....
    See more | Go to post

    Leave a comment:

  • 2many
    started a topic Good video on LED TV disassembly?
    in Troubleshooting TVs and Video Sources

    Good video on LED TV disassembly?

    Is there a good youtube video showing how to disassemble a LED TV? The ones I've found make it look too easy and does not show the hard part, which is not taking the screws out but unsnapping the bezel and the back cover after the screws are removed. The 50" Toshiba I fixed recently has these interlocking snaps which have opposing snaps and you have to twist the bezel one way to disengage one snap then twist the other way to disengage the other snap. Is there a tool that helps or is it all by fingers? The ones in the corner are especially difficult to undo and that is where a tool is really...
    See more | Go to post
    Last edited by 2many; 08-02-2016, 11:56 AM.
  • 2many
    replied to Help with Toshiba 50L2300U
    in Troubleshooting TVs and Video Sources
    Re: Help with Toshiba 50L2300U

    Can someone help me find a schematic to the PS
    board below? Even though the set is fixed and working, I'd like to know what those parts that blew do and what the circuit looks like.

    The 2 stickers are

    B178-B01 C52 REV.C 20 00014 19296 02366

    03-PK101W01001-VDAFL-C50-5100-100...
    See more | Go to post
    Last edited by 2many; 08-02-2016, 11:47 AM.

    Leave a comment:

  • 2many
    replied to Help with Toshiba 50L2300U
    in Troubleshooting TVs and Video Sources
    Re: Help with Toshiba 50L2300U



    I couldn't find the original Mosfet P0920ATF on Ebay and had to substitute a TO-220 Mosfet with a higher rating that was available on Ebay. I have never seen an isolated tab form factor like that before. What is it called? Where is the best place to buy these parts?

    P0920ATF is 200 V 9 A, the replacement is an IRF640 200 V 18 A. I don't think I can find a Nylon screw tomorrow easily and want to put the set back together. I am goind to use a zip tie, let it run a bit and if it does not get too warm, just leave it at that....
    See more | Go to post
    Last edited by 2many; 07-30-2016, 08:00 PM.

    Leave a comment:

  • 2many
    replied to Help with Toshiba 50L2300U
    in Troubleshooting TVs and Video Sources
    Re: Help with Toshiba 50L2300U

    I am glad the power supply blew and not the LED's. To prolong the life of the LED's, what level should I set the backlight to?
    See more | Go to post

    Leave a comment:

  • 2many
    replied to Help with Toshiba 50L2300U
    in Troubleshooting TVs and Video Sources
    Re: Help with Toshiba 50L2300U

    Good news! Set powers on and I have backlight!

    See the middle Mosfet? It has a metal tab, unlike the other 2 which is plastic. I didn't have any TO-220 mica insulators so made one from insulator from a hair dryer, put Silicon paste on it and screwed it down with the metal screw that was removed. I wasn't thinking and got screwed by that screw ha ha which in effect grounded the drain of that Mosfet! I took the screw out and the TV powered up and I have backlights, sound and picture!. Kudos to the designers which prevented...
    See more | Go to post

    Leave a comment:

  • 2many
    replied to Help with Toshiba 50L2300U
    in Troubleshooting TVs and Video Sources
    Re: Help with Toshiba 50L2300U

    With main board connected, shouldn't pin 12 power_tv normally be at 0 V? When you push the power button, then pin 12 should change to some voltage level?
    See more | Go to post

    Leave a comment:

  • 2many
    replied to Help with Toshiba 50L2300U
    in Troubleshooting TVs and Video Sources
    Re: Help with Toshiba 50L2300U



    Main board still disconnected, just soldered a 1k resistor across pins 14 & 12 (5.1 v and power_tv). Only change is to pin 12 (power TV), which = 4.9 V. AC_Detect is still 0 V....
    See more | Go to post

    Leave a comment:

  • 2many
    replied to Help with Toshiba 50L2300U
    in Troubleshooting TVs and Video Sources
    Re: Help with Toshiba 50L2300U

    Moreno83, please read the first post in this thread. It gives a history of what transpired.
    See more | Go to post

    Leave a comment:

  • 2many
    replied to Help with Toshiba 50L2300U
    in Troubleshooting TVs and Video Sources
    Re: Help with Toshiba 50L2300U



    That is not correct. The TV was powering up with the remote and had sound but no backlight (no picture unless I shine a flashlight on the screen). After I replaced 2 diodes and a FET on the LED power section, it stopped powering up.

    I buzzed out the IR board and LED indcator connector harness to the main board and there was good continuity on all wires. I thought I may have broke some of those wires during front bezel removal but they are fine....
    See more | Go to post

    Leave a comment:

  • 2many
    replied to Help with Toshiba 50L2300U
    in Troubleshooting TVs and Video Sources
    Re: Help with Toshiba 50L2300U



    OK. With main board disconnected, pins 10 & 14 = 5.1 V, all other pins = 0 V...
    See more | Go to post

    Leave a comment:

  • 2many
    replied to Help with Toshiba 50L2300U
    in Troubleshooting TVs and Video Sources
    Re: Help with Toshiba 50L2300U

    The SR5200 Schottky diodes arrived this afternoon from China. I replaced the 2 ultra fast diodes with them but it didn't help, still won't power up.
    Can't believe it was powering up and had sound before I did work on the power supply board, afterward that it wouldn't power up no more!

    What do the voltage readings above indicate?

    I can really use some help or a service manual / schematic.
    See more | Go to post

    Leave a comment:

  • 2many
    replied to LED backlight tester circuit
    in General Electronics Technical Discussion
    Re: LED backlight tester circuit



    I am trying to fix the PS. See this thread [url]https://www.badcaps.net/forum/showthread.php?t=55987[/url]

    power supply board number is there.Re: LED backlight tester circuit<br ...mber is there.Re: LED backlight tester circuit



    I am trying to fix the PS. See this thread [url]https://www.badcaps.net/forum/showthread.php?t=55987[/url]...
    See more | Go to post

    Leave a comment:

  • 2many
    replied to Help with Toshiba 50L2300U
    in Troubleshooting TVs and Video Sources
    Re: Help with Toshiba 50L2300U

    Where can I get a schematic/ service manual for my Toshiba 50L2300U? I searched these 2 resources from LongJohns but could not find my TV

    [url]http://www.electronica-pt.com/index....,select/id,13/[/url]

    or

    [url]http://www.eserviceinfo.com/[/url]Re: Help with Toshiba 50L2300U<br />...t/id,13/[/url]
    See more | Go to post

    Leave a comment:

  • 2many
    replied to Help with Toshiba 50L2300U
    in Troubleshooting TVs and Video Sources
    Re: Help with Toshiba 50L2300U

    You have the exact same set? I'll keep you in mind if I can't fix it.
    See more | Go to post

    Leave a comment:

  • 2many
    replied to LED backlight tester circuit
    in General Electronics Technical Discussion
    Re: LED backlight tester circuit

    But getting to the LED strips is a big job, which I am not ready to do, that's why I want to power them up with a test power supply. A multi-meter on the diode test mode can only test individual LED's, not when a bunch of them are in series as wired in a TV. I'm not sure if you can get a reading on a bunch of LED's in series even with the multi meter in the meg ohm scale.
    See more | Go to post

    Leave a comment:

  • 2many
    started a topic LED backlight tester circuit
    in General Electronics Technical Discussion

    LED backlight tester circuit

    From what I've read, LED backlights on TV's run between 90V to 120 vdc. I know my power supply is bad but want to build a LED tester to see if my LED's are good. If they are bad, I will stop any further work in trying to fix the TV since replacement LED strips are not available for this set, which limits me to replacing individual LED's, which I do not have the tools for at the moment.

    Anyone built their own LED test power supply?
    For a crude LED tester, I was thinking of using 120 v ac line voltage, a half wave rectifier, a 500 uf filter cap and a current limiting resistor....
    See more | Go to post
    Last edited by 2many; 07-30-2016, 08:33 AM.
No activity results to display
Show More
Working...
X