Toshiba CZ32V51 - vertical hold issue

[zaphod7501]

I don't need the service manual right now, but if it's not that much trouble to get it, might be nice to have it for future use. But don't use up any favors getting it as it's not needed now.

I'd have to scan it to copy it. I'll always have access to it when needed. He still does some TV repair as a sideline business so he can't permanently give it up.

[The Robman]

No probs, no need to scan. If and when it's needed again, we know where it is.

[dougxjet]

1999 Toshiba! Model # CZ32V51

My vertical hold starts scrolling with the brighter depicted scenes of any show or channel being viewed. This problem started out on an occasional basis and has increased to 40 or 50% of the time.

I am good at fiddling with things but have almost never used the soldering gun I inherited from my father. I certainly have never cracked the case of a TV set. That being said, I just rebuilt a good laptop. Love the TV and would like to fix it. Flat screens are not in the budget for a few more years. Is there any way you could explain to me in 3 yr old language how I might go about fixing this old thing.

Any help or advise would be greatly appreciated!

Thanks,

Doug

I'm in the DFW area.

[The Robman]

If your problem is also caused by cold solder joints on the Vertical output IC, as mine was, here's what you need to do:

1. Unscrew the screws holding the rear cover in place.
2. Remove the rear cover.
3. Slide out the main circuit board. If I remember correctly, it was held in place with one screw. To get it to slide out, I also needed to disconnect a couple of small cables.
4. Identify the Vertical output IC. The highlighted item in the pic below is a transistor that was loose on my board, the output IC is the item to the left of this (as we look at the pic) with the larger heat sink (with the 4 prongs).
5. Flip the board over and re-solder the pins for this chip.

[dougxjet]

Ok! Great Tips. What about that secondary Chip you were talking about to the left. You called it the vertical output IC (integrated chip?). I believe you said "it's a Toshiba TA8427K" in a previous post. Is this the same one you were talking about. I was wondering if you wouldn't mind circling it for me. It looks to be the black chip horizontally oriented on the bottom of the heat disipation(sp) (four pronged) metal.

Just to clarify that my described problem is similar to yours? Also, when I use the soldering iron... do I need to heat up the place on the board(on the revese side) where the solder is to be placed? Will it sufice to re-heat the solder that is already in place. That is what was needed on the laptop I rebuilt (heat Lamp and cardboard cutout over the video chip).

One more Q, thanks. Do I need to worry about excess electrical charge anywhere inside the box? .....capacitors?....

Thanks for the time spent.

Doug

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[The Robman]

The chip circled in green is the vertical output IC chip that you will need to re-solder. The transistor circled in red was also loose on my set, but it will probably be OK on yours.

To re-solder you will need an iron and some solder. Have the solder in one hand and the iron in the other. Touch the tip of the iron against the pin that you want to re-solder and let it heat up the existing solder, then add some more, then withdraw the iron and let the solder set.

Ideally, the solder should look like Hershey's Kisses when it sets. If it looks like a ball, it's probably not good.

I'll let the electronics experts address your other questions, but my guess is that you don't want to be doing this just seconds after disconnecting the power.

[zaphod7501]

1999 Toshiba! Model # CZ32V51

My vertical hold starts scrolling with the brighter depicted scenes of any show or channel being viewed. This problem started out on an occasional basis and has increased to 40 or 50% of the time.

I am good at fiddling with things but have almost never used the soldering gun I inherited from my father. I certainly have never cracked the case of a TV set. That being said, I just rebuilt a good laptop. Love the TV and would like to fix it. Flat screens are not in the budget for a few more years. Is there any way you could explain to me in 3 yr old language how I might go about fixing this old thing.

Any help or advise would be greatly appreciated!

Thanks,

Doug

I'm in the DFW area.

More likely would be capacitor failure or deterioration. This brand is notorious for a couple of these failing. They can often be spotted by their color. Most of them are gray plastic covered but the bad ones use red or brown plastic covers. One is near the output IC but the other is usually located neat the processor chip. I'll have to locate a full service manual to find any more info.

It could also be a power supply problem or a high voltage feedback issue. Intermittent loss of vertical output is fairly simple but I fear your issue is more complex.

[dougxjet]

I am greatful for your input. I will be listening in. I have a few weeks before i will be able to tackle this. Hopefully it is something simple. Time to go to work for a few days.

Many thanks again for your effort. I will check back in a few days to see if there is more info.

Doug