Author Topic: Sharp LC-42DH77E  (Read 16520 times)

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OldLes

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Re: Sharp LC-42DH77E
« Reply #30 on: December 12, 2013,15:04:46 »
Turnip, I am quite satisfied with the connections. The originals fail where they clip onto the board, and it seems even good ones fail next time you refit them. I cut the top off the clips, "wire wrapped" them with the silver plated copper wire, crimped tight and left a tail. Fitted them onto CCFLs with tails sticking up.
Soldered THIN flexible leads to every solder pad on the PCB, refitted the PCB, snipped my tails at an appropriate length, the soldered the flex tails to the rigid tails. As a repair, I regard that part as a 100% fix that you must NOT do for a customer. (H&S Gestapo)
I have been thinking about it today. I definitely shorted out the correct cap (second time around), but it refuses to display the "K" service menu. Why on earth do they not give the circuit of the inverter board, when EVERYTHING else is shown? I may try to trace it to see if I can figure it out. Either that, or back to the tip with deep regrets!
Les.

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Re: Sharp LC-42DH77E
« Reply #30 on: December 12, 2013,15:04:46 »

downunder

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Re: Sharp LC-42DH77E
« Reply #31 on: December 13, 2013,04:40:27 »
Old Les,
A couple of bulletins for you to peruse. Para 7 on page 2 of Bulletin CTV236R looks interesting.
« Last Edit: December 13, 2013,04:47:59 by downunder »

Kilroys

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Re: Sharp LC-42DH77E
« Reply #32 on: December 13, 2013,07:15:56 »
Back to basic
Cut or unsolder the wire that shorted c7561.
It was useless, c7561 goes to  over voltage protections.
My mistake,  looked at the 37dh77 inverter.
Look at the CP signal at pin 3 in the block diagram. Can perhaps be something to be shorted
What happend when you are holding down the power button,
and plug in the AC power cord to turn on the power.
If you see the upgrade screen,  try then to make a
upgrade.
« Last Edit: December 13, 2013,07:19:10 by Kilroys »

Mulja tv repair portal

Re: Sharp LC-42DH77E
« Reply #32 on: December 13, 2013,07:15:56 »

OldLes

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Re: Sharp LC-42DH77E
« Reply #33 on: December 13, 2013,12:44:50 »
Kilroys, thanks for this. It had occurred to me that there must be something wrong with that link, or the possibility that the earlier link I did had caused problems.
Hopefully may get to look at it Monday, but it MAY have to wait until after Xmas. (I hope to have a joiner fitting a wardrobe, and a roofer doing some roof work).
Can I suggest you edit your earlier advice re. C7561, as anybody reading this from scratch could get it wrong like me.
I was NOT wanting to scrap this set, but was getting to the stage where is was next move. Hopefully the study of the diagram and a bit of googling chips may help get a solution.
Les.

Turnip

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Re: Sharp LC-42DH77E
« Reply #34 on: December 15, 2013,12:33:23 »
Hi, Old Les,

Only had the one, and after doing the check tube biz, where none were faulty, suspected main prob was those edge conectors, so hard wired the lot.

Set not back yet, guess poss there are now other probs, but not yet met 'em.

Keep us on board with thoughts - Chris.

Mulja tv repair portal

Re: Sharp LC-42DH77E
« Reply #34 on: December 15, 2013,12:33:23 »

 

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