Sharp LC-60LE600U no op - waveforms

[dick_barton]

Re: Sharp LC-60LE600U no op - waveforms

I would read up on the threads on this site about lifting the panel away and how people have done such a large panel. Suspect it's a two person operation.
Do not mix up the direction and position of the filters screens behind the panel or you will be in trouble.

Have a look at this page

[legg]

Re: Sharp LC-60LE600U no op - waveforms

I rigged up a more rugged substitute with the right profile, then showed the result to my neighbor, for whom I'm doing the work as a favor. He didn't seem distressed by the darkish corner of the resulting display. He knows how much the replacement lamp will be and knows the amount of work involved.

Wrap it up, he says. He'll live with it.

I suspect a lot of owners would have said the same, if, in the original design, one lamp section failure didn't cause the whole unit to die.

Imagine other equipment doing the same thing.

One windsheild wiper craps out and your car locks up.......

oh, wait.......that's exactly what happens with some models, isn't it.

[dick_barton]

Re: Sharp LC-60LE600U no op - waveforms

I'm a little puzzled here. I thought the backlights were failing to come on because you found a faulty led string but now you say

I rigged up a more rugged substitute with the right profile, then showed the result to my neighbor, for whom I'm doing the work as a favor. He didn't seem distressed by the darkish corner of the resulting display. He knows how much the replacement lamp will be and knows the amount of work involved.

[mmartell]

Re: Sharp LC-60LE600U no op - waveforms

The first sentence is what you're looking for. He's running a dummy load in place of the offending string to keep the supply happy.

[dick_barton]

Re: Sharp LC-60LE600U no op - waveforms

So the dummy load did work.

[legg]

Re: Sharp LC-60LE600U no op - waveforms

A firm 'itive'.

Considering the flammability of the materials in one of these displays, I might sympathize with the protective function used in the thing, however I'm guessing it was just easier/cheaper to do. Given the reluctance of the bad string to arc on a flare, or draw anything when probed to double normal voltages in testing, there seems little likelihood of it doing so in the future, unstressed and cold.

I've attached a schematic of the final plate assembly used. Drawing from the junk pile, it used metal clad mil spec parts bolted to the plate - which was mounted on the empty metal panel above the main board, on unused stand-offs pre-existing there. No big rise in air resulted, probably due to the unchanged power consumption in that area.