My neighbor gave me a lcd tv that would power up fine and display the memorex logo sometimes for as long as 5 minutes then go dark. Flashlight shows a picture and it has sound. When the backlights came on you could hear a buzzing coming from the corner of the panel so i suspected bad ccfls. I tore the panel down to get the ccfls out and found they were indeed bad. Two on top and two on bottom. Both the bottoms were completely shot and only one on the top is good. Looked around for a few minutes to price new bulbs and decided to try out some leds. Ordered a 16 foot roll of flexible smd led ribbon that can be cut to fit for 15 bucks. Only need two 16 inch pieces but i can find something to do with the other 13 feet. Anyway, i'll post some pics when i get the leds installed.
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Re: Memorex mlt1921 converting ccfl to led
Yeah no need for the inverters on this one. It has a proview power supply with the inverters built in to it. These led strips operate on 12 volts dc. I looked for a service manual for this tv so i could maybe find my 12 volts on the boards somewhere but no luck. All i could find was the 32" version. I have a box full of 12 volt dc power supplies, so one of them will likely be put into play. One end of the strip has a dc jack and the other end has terminals of some sort.
I dont have a spec sheet for them but a buyer on amazon did some measurements of his.
"I made a few current measurements. 3 LED (minimum strip size) consumes 24 mA. 300 LED (entire 16.4' roll) consumes 1.737 Amps. Each 3 LED section has a 150 Ohm resistor to limit current. A small SLA 12V battery will run a small strip for days/weeks."
If it does come with a spec sheet i'll post it so people can give me some input on what they think. It says they're 6000k and you can get a dimmer for 6 or 7 bucks. It should be a cool project once i get all the stuff in order. I tried to upload some pics of the boards and the bad bulbs last night but no luck. I'm using my 3g wifi hotspot from my samsung phone for the laptop. If the galaxies aren't aligned just right it will not upload a picture. I'll try again later.Comment
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Re: Memorex mlt1921 converting ccfl to led
Doesn't a tv make adjustments to how bright the CCFL is normally using the DIM pin? If so how would that work with an LED light source being on all of the time?Comment
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Re: Memorex mlt1921 converting ccfl to led
I am interested in doing this to a monitor. Can you post details on where you purchased your supplies, and maybe a schematic for driving the LEDS?Comment
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Re: Memorex mlt1921 converting ccfl to led
kits are sold even on Ebay, but thery are not cheap. you can check out Youtube too.Comment
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Re: Memorex mlt1921 converting ccfl to led
Installed the leds today and the tv works. The picture is nice and bright. I tried uploading pictures but i'll have to wait until i get the laptop down to some decent internet. You can faintly see the leds shining on top and bottom in the picture but that was to be expected and it doesn't bother me much. The leds didn't come with a spec sheet so i can't tell you much more about them other than what i've already posted. I got them on amazon.com for 15 bucks.Comment
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Re: Memorex mlt1921 converting ccfl to led
I tried uploading some pics but it wont do it at home. I'll do it tommorow. I've been sidelined for a while and havent really been working on any thing. A dog bit the tip of my finger off and i had to have surgery.
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Re: Memorex mlt1921 converting ccfl to led
Pics as promised. i"ll take some better ones where you can see the leds shining brighter at the top and bottom.Attached FilesComment
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Hi there !
I'm having an issue for several weeks with my quite old K70 LUX RGB keyboard. I haven't used it for few months, and once I setup up again my desktop computer, I got several dead LEDs on that keyboard. I tried the Corsair troubleshooting thing (disabling options in iCUE, ...) but nothing changed so I conclude that for some reason some LEDs went in retirement...😅
Decision taken to change these LEDs as I have access to desoldering iron and binocular magnifier, I wrote a ticket to tech support, hopping to obtain the LEDs reference and... They refused to tell me 🙄...10-08-2024, 11:58 AM -
Greetings everyone,
I have a HANNSG Hi221 monitor that exhibits two seconds to black issues (backlight goes off, display is still on as confirmed by shining a flashlight on it) with some additional oddities...
The monitor failed on me with a standard "2 seconds to black" some time ago prompting me to initially replace most of the electrolytic capacitors (some of them were bulging/leaking).
Things kinda sorta worked for a night, then the problem returned along with some flickering and "buzzing" noises.
Upon closer inspection... -
Hi,
This monitor previously is my main working monitor which i have been using for 8~9 years. Yesterday, when i switched on my pc from fresh to power on, the monitor is just black no display. I started dismantle to look inside the monitor power board but nothing looks suspicious or burnt. So i took my external ccfl inverter to try to power the monitor ccfl lamps which consisted of 2 lamps on upper part and 2 lamps on the lower part.
Found out the upper ccfl lamp which is supposed to connect to cn304 on the power board did not light up. Then i installed a used working... -
I am currently on a troubleshoot of 46” Sony KDL-46BX450 tv. I came back from Washington to Texas on medical emergency and had to leave all my tools up there. All I have is a couple of screwdrivers and a dvm. I wish to ask the community a troubleshooting question. Please forgive stupid questions as meds I am taking produce brain fog.
I have well maintained Sony KDL-46BX450. It went black one day. After turn-on, I get solid green light and Sony logo in screen center for about 1-2 seconds, then black. No blinking LEDs, no hissing. Flashlight test shows screen characters dimly viewable,... -
So I use this TV daily as a second monitor for my PC or my Playstation - at one point a few months back I tried to fix the problem - but in the process, I figured out something that works so I haven't posted this for awhile. It is an annoying trick to have to do though, so I decided to post about it to see if anyone could spot what's wrong. It baffles me because it works on it's own half the time.
When I first got this TV, I was told it wouldn't turn on, and of course I did the flashlight test, and the image was there. Also, the red LED on the front indicated that it had power (it...
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