Is this 55" Hitachi a good buy? (lines on screen)

[tom66]

Re: Is this 55" Hitachi a good buy? (lines on screen)

Yeah, trace the wires from Xsus to PSU.

[mattpd]

Re: Is this 55" Hitachi a good buy? (lines on screen)

Yeah, trace the wires from Xsus to PSU.

The harness that goes from psu to xsus does not include Vs in any of the labels. Only the harness that connects X and Y have the Vs label. In the service manual it shows where a test pin for Vs on the PSU. I tested it, and I get nothing...

EDIT: The harness that is going from PSU to Xsus is labeled "VSI" "VAI" and "VCC"... Is VSI the same as VS?

[tom66]

Re: Is this 55" Hitachi a good buy? (lines on screen)

with X-sustain disconnected?

[mattpd]

Re: Is this 55" Hitachi a good buy? (lines on screen)

With the power unhooked from Xsus and Ysus (all the ribbons are still connected, is this ok?) there is no Vs coming off of the PSU. So I guess the pop came from the PSU? But the TV still powers on with sound... Possible just the Vs rail broke?

[tom66]

Re: Is this 55" Hitachi a good buy? (lines on screen)

Possibly, do you have Va/Vda/Vdata?

[mattpd]

Re: Is this 55" Hitachi a good buy? (lines on screen)

I will have to bring home my good meter from work tomorrow and test.

[mattpd]

Re: Is this 55" Hitachi a good buy? (lines on screen)

I have read that IPMs often produce a pop when thy fail. How can I identify which chip is an IPM?

Also, aren't the two boards on the sides of the plasma panel normally called y and z? I just noticed this hitachi calls the one to the right x.

[tom66]

Re: Is this 55" Hitachi a good buy? (lines on screen)

On LG, the rightmost board is Z, but everyone else uses X.

I doubt this set uses IPMs. It will all be discrete if it is a Hitachi. That is, all MOSFETs, IGBTs and diodes. But if you post a picture, I'll be able to tell for sure.

[mattpd]

Re: Is this 55" Hitachi a good buy? (lines on screen)

It would be a rather large chip under a heat sink, right? I don't see one...

[tom66]

Re: Is this 55" Hitachi a good buy? (lines on screen)

No IPMs, all discrete. Good on Hitachi...

[mattpd]

Re: Is this 55" Hitachi a good buy? (lines on screen)

Do transformers go pop when they fail? I have been over the board with a jewelers loop and cant find anything that looks broken.

[tom66]

Re: Is this 55" Hitachi a good buy? (lines on screen)

No, they very rarely fail.

Things to look out for would be ICs near the MOSFETs/IGBTs.

[mattpd]

Re: Is this 55" Hitachi a good buy? (lines on screen)

Just out of curiosity I put my blue ring tester on the transformers and there is one that does not ring at all. I tried all combinations of pins.

[tom66]

Re: Is this 55" Hitachi a good buy? (lines on screen)

That's odd.... which one is it? (Can you highlight it on the image for me.)

[mattpd]

Re: Is this 55" Hitachi a good buy? (lines on screen)

White one that is in the bottom left corner. 25-217

It rings on the pins to the right, but nothing but shorts on the left.

[mattpd]

Re: Is this 55" Hitachi a good buy? (lines on screen)

And on the other white transformer, the best result I can get is 1 yellow LED. This one rings OK on the left side, and not so well on the right side.

[tom66]

Re: Is this 55" Hitachi a good buy? (lines on screen)

That might indicate a short on the board somewhere. Sorry I'm not much help... I have no experience with Hitachi plasma panels. What's the part # of the board? Maybe it's cheap somewhere else...

[mattpd]

Re: Is this 55" Hitachi a good buy? (lines on screen)

Its ND60200-0032

I guess I should have checked the board prices before I picked up the TV.

[tom66]

Re: Is this 55" Hitachi a good buy? (lines on screen)

I found a surplus of the ND60200-0038 (18 boards on one site, £30 each), but it's not the right one, it's completely different. Had a look around for similar models with cracked screens?

[mattpd]

Re: Is this 55" Hitachi a good buy? (lines on screen)

Yeah, that's the 42" version I think. It's parts are much cheaper. Nothing on craig's list yet... Please, if anyone has or knows of any of these TVs with a cracked screen, please PM me.

HITACHI 55HDS52
HITACHI 55HDS69
HITACHI 55HDT52
HITACHI 55HDT79
HITACHI 55HDX62
HITACHI 55HDX99