# Powering LEDs from a broken LED/LCD TV.

• posted on January 10, 2014, 8:23 pm
Hope this link works. I occasionally part out newer TVs that have had the screen broken. I decided I'd try to get a set of LED's to light up. Got 8 of these strips out of a 46" Samsung. I ramped up the voltage till I got pretty good illumination. Ended up with 48v and about 1/3 amp to do one st rip. In the picture I have a 10ohm resistor but it works without a current limiting resistor. I just had this one in the circuit so I could calculat e current. The mounting board seems to get warm so I suspect the current l imiting is built into the strip. I'm thinking about using these for some o utdoor lighting projects.
https://scontent-b-pao.xx.fbcdn.net/hphotos-prn1/1535537_10200527055738595_ 1975206785_n.jpg
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• posted on January 11, 2014, 2:50 am

Don't know about the limiting, but I like the variac. Used to use one that also had meters.
Greg
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• posted on January 11, 2014, 3:25 am
On Friday, January 10, 2014 2:23:32 PM UTC-6, jamesgang wrote:

screen broken. I decided I'd try to get a set of LED's to light up. Got 8 of these strips out of a 46" Samsung. I ramped up the voltage till I got pr etty good illumination. Ended up with 48v and about 1/3 amp to do one strip . In the picture I have a 10ohm resistor but it works without a current lim iting resistor. I just had this one in the circuit so I could calculate cur rent. The mounting board seems to get warm so I suspect the current limitin g is built into the strip. I'm thinking about using these for some outdoor lighting projects. https://scontent-b-pao.xx.fbcdn.net/hphotos-prn1/1535537 _10200527055738595_1975206785_n.jpg
That sure looks like a Harbor Freight multimeter sitting there!!!!
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• posted on January 11, 2014, 2:43 pm
snipped-for-privacy@sbcglobal.net wrote:

Why? It's not a cen-tech multimeter which is HF's brand.
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Bill
In Hamptonburgh, NY
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• posted on January 11, 2014, 3:39 pm
On 1/11/2014 9:43 AM, willshak wrote:

Cen Tech typically have the leads on the lower right, front.
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Christopher A. Young
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• posted on January 11, 2014, 4:56 pm
On 01/10/2014 07:25 PM, snipped-for-privacy@sbcglobal.net wrote:

The case is similar, but the label says it's a "Windward Multimeter WP2000". I looked it up but I can't find a reference to anything by that name, or even by that company. Hmmm....
Jon
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• posted on January 12, 2014, 4:27 am
On Fri, 10 Jan 2014 12:23:32 -0800 (PST), jamesgang

You will probably want some current limiting in there for your project. You can't count on the line voltage being constant and the current will vary wildly depending on the voltage. You're unlikely to get an integral number of strips to work out to the right voltage, either.
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• posted on January 12, 2014, 5:54 pm
On Saturday, January 11, 2014 11:27:05 PM UTC-5, snipped-for-privacy@attt.bizz wrote:

he screen broken. I decided I'd try to get a set of LED's to light up. Go t 8 of these strips out of a 46" Samsung. I ramped up the voltage till I g ot pretty good illumination. Ended up with 48v and about 1/3 amp to do one strip. In the picture I have a 10ohm resistor but it works without a curr ent limiting resistor. I just had this one in the circuit so I could calcu late current. The mounting board seems to get warm so I suspect the curren t limiting is built into the strip. I'm thinking about using these for som e outdoor lighting projects.

95_1975206785_n.jpg

I'm thinking I'll go with a 48v switching power supply. They are pretty ch eap on flea-bay. The tv power supply says the led voltage was 122 vdc. I guess two strips in series. The strips all connected to a distribution str ip running down the side, I should have checked that out closer but I threw it away with the tv plastic and wires. The led strip is actually 2 strips that connect about 2/3 of the way down. They are in series because it doe sn't light if you disconnect the second segment. I'm thinking they use dif ferent length 2nd sections for different size tv's. I got 8 sets of these out of this 46" tv.
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• posted on January 12, 2014, 12:56 pm
On Fri, 10 Jan 2014 12:23:32 -0800 (PST), jamesgang

--
If there's a current limiter in there, then once it kicks in the
voltage across the 10 ohm resistor will stay constant if the input
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• posted on January 12, 2014, 5:59 pm
On Sunday, January 12, 2014 7:56:57 AM UTC-5, John Fields wrote:

he screen broken. I decided I'd try to get a set of LED's to light up. Go t 8 of these strips out of a 46" Samsung. I ramped up the voltage till I g ot pretty good illumination. Ended up with 48v and about 1/3 amp to do one strip. In the picture I have a 10ohm resistor but it works without a curr ent limiting resistor. I just had this one in the circuit so I could calcu late current. The mounting board seems to get warm so I suspect the curren t limiting is built into the strip. I'm thinking about using these for som e outdoor lighting projects.

95_1975206785_n.jpg

I can't really figure out why else the board would get warm. It's got pain t over it so I can't really trace anything on it. There are a few surface mount parts on it besides the leds but they are small so I can't see them b eing much of a current limit at a 1/3 of an amp. I cranked the voltage up into the 50s but it didn't get much brighter so I figure 48v is safe. I've run it at 48v for about 30 hours now.
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• posted on January 16, 2014, 7:10 pm
On Sunday, January 12, 2014 12:59:14 PM UTC-5, jamesgang wrote:

the screen broken. I decided I'd try to get a set of LED's to light up. Got 8 of these strips out of a 46" Samsung. I ramped up the voltage till I got pretty good illumination. Ended up with 48v and about 1/3 amp to do o ne strip. In the picture I have a 10ohm resistor but it works without a cu rrent limiting resistor. I just had this one in the circuit so I could cal culate current. The mounting board seems to get warm so I suspect the curr ent limiting is built into the strip. I'm thinking about using these for s ome outdoor lighting projects.

8595_1975206785_n.jpg

int over it so I can't really trace anything on it. There are a few surfac e mount parts on it besides the leds but they are small so I can't see them being much of a current limit at a 1/3 of an amp. I cranked the voltage u p into the 50s but it didn't get much brighter so I figure 48v is safe. I' ve run it at 48v for about 30 hours now.
My \$8, 10amp, 48vdc power supply showed up. Tried a strip on it with no re sistor. Seems to work fine.
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• posted on May 1, 2015, 5:19 pm
On Friday, January 10, 2014 at 3:23:32 PM UTC-5, jamesgang wrote:

e screen broken. I decided I'd try to get a set of LED's to light up. Got 8 of these strips out of a 46" Samsung. I ramped up the voltage till I go t pretty good illumination. Ended up with 48v and about 1/3 amp to do one strip. In the picture I have a 10ohm resistor but it works without a curre nt limiting resistor. I just had this one in the circuit so I could calcul ate current. The mounting board seems to get warm so I suspect the current limiting is built into the strip. I'm thinking about using these for some outdoor lighting projects.

5_1975206785_n.jpg
Hi there,
the link apparently no longer works and i was wondering if you can help me out, my son is trying to get the LED's from an old 46" samsung t.v. to ligh t up, but for some reason they are not. is it possible to light up just on e section or both must be put together? Also what kind of power supply do we need? 24 volts or 48 volts?
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• posted on May 3, 2015, 4:35 pm
On Fri, 1 May 2015 10:19:24 -0700 (PDT), snipped-for-privacy@gmail.com wrote:

can help me out, my son is trying to get the LED's from an old 46" samsung t.v. to light up, but for some reason they are not. is it possible to light up just one section or both must be put together? Also what kind of power supply do we need? 24 volts or 48 volts?
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You'll probably get more help on the newsgroup sci.electronics.basics or any of the other "sci.electronics.______ newsgroups. Those NGs are fairly active and there are some knowledgable people there. I like to tinker with electronics myself, but I cant answer your question. However, if you could find a schematic for that TV, it would likely show you the needed voltage.