Using Element 42" As Light Source

[Michale32086]

I had an Element 42" in with a busted screen. I have always wanted to use such a critter to be a good light source for my workbench.. (see pic)

But I have 2 issues with it..

1- I hate to waste a video A board when it's not really needed for my use

B- It always shuts down after x minutes. Idle timer probably..

Is there a way to short the A Board connector so that it stays on and frees up the A Board for other use...

I realize the exact model number of the Element is likely required. I'll have that in a few.. But I just wanted to get a general idea if it's even possible..

[Michale32086]

Re: Using Element 42" As Light Source

TV is an ELEMENT ELDFT404

[tom66]

Re: Using Element 42" As Light Source

Yes, would be pretty easy. Post a picture of the power board connector (should have labels next to it)

[Michale32086]

Re: Using Element 42" As Light Source

Damn!! I knew I shoulda checked this before heading home!

I'll follow up in the morning..

Thanx...

[Michale32086]

Re: Using Element 42" As Light Source

Here are the (what I assume to be) relevant connectors off that Element 42"

[tom66]

Re: Using Element 42" As Light Source

Hmm odd, no BL ON/OFF pin, could you supply a picture of the whole TV board arrangement, and one of each of the power & main boards?

[Michale32086]

Re: Using Element 42" As Light Source

Hmm odd, no BL ON/OFF pin, could you supply a picture of the whole TV board arrangement, and one of each of the power & main boards?

Attached

[tom66]

Re: Using Element 42" As Light Source

Ok, that little 6 pin connector to the right of the main power board one (on the main board), does that go off to the inverter?

[Michale32086]

Re: Using Element 42" As Light Source

Yea, that goes over to the Buffer Board (??) on the left of the unit..

[Michale32086]

Re: Using Element 42" As Light Source

I finally got a nice 8MP camera to use. So if you need any close ups of connectors I can do it now...

[tom66]

Re: Using Element 42" As Light Source

That's actually the inverter. What you'll need to do is use three resistors and the power supply/inverter. The rest, you don't need.

Connect pin STB to 5VSB with 100-470 ohm resistor.
Connect each of the two connected pins on the 6 pin connector to 5VSB also with a 100-470 ohm resistor.

Plug the set in and the BL should come on fully.

[Michale32086]

Re: Using Element 42" As Light Source

That's actually the inverter. What you'll need to do is use three resistors and the power supply/inverter. The rest, you don't need.

Connect pin STB to 5VSB with 100-470 ohm resistor.

OK, that's simple enough..

Connect each of the two connected pins on the 6 pin connector to 5VSB also with a 100-470 ohm resistor.

This is a little more dicey... The 6 pin connector has 4 wires going to the Main Board.. Plus there are two wires going from the Main Board to the Inverter..

[tom66]

Re: Using Element 42" As Light Source

I mean the 6pin between main & inverter.
You can remove the main board and its connections entirely.

[Michale32086]

Re: Using Element 42" As Light Source

I mean the 6pin between main & inverter.
You can remove the main board and its connections entirely.

OK, I see where I am screwing up..

I thought you meant the "6 pin" on the Power PCB.. Which is actually an 8-pin which caused me to read your posts more closely...

You are talking about the 6-pin on the A/Main Board that only has two wires..

OK, NOW it all makes sense..

I don't need a ton of bricks to fall on me.. well, not ALWAYS..

Thanx.. I'll dig up the resistors and give it a go...

[Michale32086]

Re: Using Element 42" As Light Source

That's actually the inverter. What you'll need to do is use three resistors and the power supply/inverter. The rest, you don't need.

Connect pin STB to 5VSB with 100-470 ohm resistor.
Connect each of the two connected pins on the 6 pin connector to 5VSB also with a 100-470 ohm resistor.

Plug the set in and the BL should come on fully.

Tom... Or anyone???

1/4 watt on those resistors?? 1/2 watt??

I seem to remember from a previous project like this that 1/2 watt was recommended.

Wanted to confirm...

[tom66]

Re: Using Element 42" As Light Source

Doesn't matter as they will be dissipating very little power... 1/4W is fine... 1/2W also fine.

[Michale32086]

Re: Using Element 42" As Light Source

Thanx.. Much appreciated..

I hope to have this project deployed today....

[tom66]

Re: Using Element 42" As Light Source

For reference ... power dissipated in a resistor P = (V^2)/R or P = (I^2)*R



Simpler to use the "V" equation. So, assume 5VSTB = 5V, and the BL ON signal is grounded internally, very low volt drop, say 0V for simplicity.

Power dissipated in a 470 ohm resistor will be: (5*5)/470 = 53mW... your resistor is rated to 1/4W (250mW)

Generally you want to keep within 70% of the resistor's rating for reliability and longevity.

[Michale32086]

Re: Using Element 42" As Light Source

Now THAT was funny!!

The fruits of our labors..

Thanx for all the help..

[tom66]

Re: Using Element 42" As Light Source

One thing, I would consider adding a fan to the PSU because in normal operation, the TV is mounted upright and cool air flows in at the bottom, hot air out the top. Mounting it laying down like that may cause the PSU to run too hot.