Toshiba 42H83 problem

[mrosenberg42]

I have a Toshiba 42H83 that I just replaced the 10uf caps in the hyper module. It looked great for a day then the picture went all crazy. I took my time in the repair but now am confused. Pics of the TV are at the link below. Any help would be apreciated. Thanks.

[mrosenberg42]

Re: Toshiba 42H83 problem

Sorry here is the pic.

[kc8adu]

Re: Toshiba 42H83 problem

a bunch of the other caps are shot too.
most of the 470's were open on the last 6 i did.
esr test useless as mlcc are in paralel.
oh and wash the board with alcohol.i have one here that had cap juice all over it.i thought it had never been defluxed but the smell when desoldering told me otherwise.

[Wizard]

Re: Toshiba 42H83 problem

Nodding. Lot more!

Low ESR 470uF caps, I use 16V or 10V caps but lot of them should do fine with 6.3V if you can check voltage to see what really is. I bend legs outwards and stand them up and solder in.

Install caps in sequence so you can get at solder pads heh, that takes some thought.

Cheers, Wizard

[Krankshaft]

Re: Toshiba 42H83 problem

I had to do this too I only replaced the 10, and the 100s didn't replace the 470s. I did this back in 07 still running fine. In the future though knowing this i'll replace the 470s too.

Does anyone know what the brand and temperature rating of the original caps were? Was it a crap caps brand?

I used Nichicon UD Series for replacements.

Be careful during removal and take your time SMD traces are much easier to rip off.

[mrosenberg42]

Re: Toshiba 42H83 problem

So, I replaced all 470uF, 100uF, and 220uF caps in the hyper module and it made no difference. The picture is exactly the same as before. What I did notice was that behind each convergence IC there are six resistors. 3 1.8ohm and 3 220ohm. The 1.8 ohm resistors measure the proper resistance but, the 220ohm resistors measue around .5ohms. Is this an indication that my convergence IC's are bad?

[Wizard]

Re: Toshiba 42H83 problem

Probably. Unsolder the pin for that resistor and measure again to vertify.

Time to bring out ESR meter and go OVER all the capacitors in the hyper module and all other modules, chassis as well. Drastic but that all I can say for now.

I'd prefer low ESR capcitors instead of what you get from other places, do you? And stop using SMD caps. I bend up the legs, trim leads and solder them in. Vastly much better than SMD.

Cheers, Wizard

[bigggjim1]

Re: Toshiba 42H83 problem

I recently purchased a Toshibal 42h83 with apparently the same hypermodule problem. I am comfortable replacing the caps, but would anyone know where to get parts diagram for the module? Any help would be greatly appreciated.

[Wizard]

Re: Toshiba 42H83 problem

Don't bother with diagram, it is visible once you get cover off the module (you need to pull the small signal board out of chassis to get four solder tabs undone first.)

Then get the board out of the module's box.

Do the whole module anyway. Use quality capacitors with low ESR not general purpose and also I don't bother with SMD caps. I use radial caps, bent the legs out at height yet reachable with soldering iron and trimmed to fit on the pads.

Clean the small area after removing several caps as you go before putting new caps in.

Don't forget to resolder the small signal board also. Especially regulators, connectors, certain jumpers mentioned everywhere else.

Cheers, Wizard