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Toshiba 43" rear projection HELP

I just aquired a Toshiba 43" rear projections television Model TP43H60 using chasis TAC9859. Upon plugging it in I hear the high voltage kick in. All three tubes glow. But no picture. I removed the front panel to reveal the control knobs for the flybacks. I toned them up a bit... now I get a pictures with a horizontal line across. then after a few seconds it scatters like a oval type shape. My thoughts since I repair video game monitors for my work.. I suspected the horizonal output transitor. Any help would be great.

--Ron snipped-for-privacy@buckeye-express.com

Reply to
Ron
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Also I saw a D2253 transistor... is this the HOT?

--Ron

Reply to
Ron

If you have any picture at all then the HOT is obviously good. What do you mean by the pic scattering? Do you have a way of measuring the HV?

Reply to
James Sweet

when the unit is powered on it will have a straight line (red green and blue) from right to left, then I hear a click and it will look like an oval type shape. Red on the other hand starts to fan out like a chinese fan on each side from the center (about 6-7 inches) I'm going to get a few pictures and post them with links on my webserver today.

--Ron

Reply to
Ron

unplugging the three connectors I get no picture. I plugged one in at a time and each appear to look like a star. then I plugged two in and I seen the straight line from left to right. then I plugged them all back in to get where I was.. I'll check resistor values later on tonight when I get some time.

--Ron

Reply to
Ron

grr.. I posted two pictures and it didn't post to the groups...

ht**tp://nnl.darktech.org/tv/tv_01.jpg ht**tp://nnl.darktech.org/tv/tv_02.jpg

Remove the ** of course..

--Ron

Reply to
Ron

You have no vertical deflection. Bad connections, or bad IC, these units are known for bad convergence IC's also. Rono.

Reply to
Rono

That's pretty screwy, at any rate horizontal deflection is fine, it's obviously a vertical problem of some sort, actually pretty likely the vertical output IC is toast, the vertical deflection you are getting could be from the convergence yokes.

Reply to
James Sweet

Update: Well I've replaced both STK392-110s with no change in the picture. Does anyone have or can download a schematic for this unit.. the model number is TP43H60 Using Chassis TAC9859. I have one capacitor in question C446... Can anyone verify that D688 is the vertical output transistor?

--Ron

Thanks for all the help.

Reply to
Ron

Have you checked the return resistors , are there any PC mount fuses ?

kip

Reply to
kip

Checked all resistors (the 1 ohm and 3.3 ohm)... All check out ok. My guess at this point would be this missing capacitor... I used my volt meter to check voltage. I get about 210-220 volts DC on the positive side of the cap. I've traced the negitive side of the cap all the way back to the flyback. of course it jumps though hoops a capacitor here and a diode. I've tried to install a 200v 1uf cap. with no change in the picture.

--Ron Baffled but learning in the process.

Reply to
Ron

I was told this DCU unit rarely fails. I need to find the value of C440. My unit seems to be missing this Capacitor for some reason. If anyone has a schematic or knows the value I would most appricate it. No one here locally has any schematics... so I reach out to those on the web for assitance. Anyone with access to the schematic or has a PDF of it I would appricate it. Toshibia points me to a service center. But I haven't heard any response.

--Ron

Reply to
Ron

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