Toshiba TV29C90 problem; Image fades to black...

[ZioGian]

The board connections strongly suggest a single power mosfet....

Hi All
First of all, thank you very much fue to your help ! You're great.
I'm working with Altomelto on the damaged mainboard. I found another
component in short circuit. this is the photo:
http://www.snipp.org/ciro/whoami.jpg
I suppose this component is a double schottky diode but I'm not sure.
Over the PCB the 2 little pinout are soldered on the same track.
Can you help me identify this component ?


ZioGian

 

[Mike Berger]

"Shuts down" is a symptom, not a problem. It usually means that there
is a condition that would draw too much current or draw power out of
specification. The TV shuts down to protect itself from further damage.

T Adamson wrote:

I went to the Funai "Contact Customer Support" site and under the "Please
describe any problem with your product" section, there's a drop down list
which "shuts down" may be selected. Is this a known problem with these
components in these units?...Is there a recall that's not publicized?

 

[JW]

On Wed, 17 Sep 2003 09:25:27 -0400 "Tardz" <yves_tardif@videotron.ca>
wrote in Message id: <QhZ9b.54665$LR.737721@wagner.videotron.net>:

Hi I have GS-790 monitor and I'm interested to have a copy of this manual,
it is possible to repost it and where can I download it. Thanks.

Sure. Keep in mind that it's only good for chassis #VCDTS21528-1, and
there was more than one chassis number for this model. Check the number on
the back, and verify. If it's the same, I will post it in either
alt.binaries.e-book.technical or alt.binaries.schematics.electronic. Let
me know which group your server carries so you can retrieve it. If your
server doesn't have either one, I'm open to suggestions on where you want
it posted. FYI, It's 10MB.

Let me know.

 

[LASERandDVDfan]

And as far as the radiation goes you'd have to practically stick it in
your eye to get enough to do any harm.
We have this thing called the Underwriters Labaratory that tests all
household appliances.

That, and you also have the Federal Communications Comission, who wouldn't
allow such a device because of the possibility of unacceptable interference, as
well as the DHHS, who would deem such items as failing to comply with human
health protection codes in terms of radiation emission standards. In either
case, if DVDs and players were so dangerously radioactive, it would be
federally illegal to sell and possess them.

The original poster's story has more holes than Bonnie and Clyde in their last
getaway attempt. - Reinhart

 

[Ross Mac]

Looks like John had the correct answer...I found the bias trim pots to be
worthless garbage and almost unadjustable. I will replace today...I did
calibrate them the best I could and the amp worked great all night....just
ask the neighbors!!...hehehe....Thanks to all for your help!
.....Ross
"John Del" <ohger1s@aol.com> wrote in message
news:20030915215847.16504.00001078@mb-m02.aol.com...

Subject: Pioneer SX 1250
From: "Ross Mac" macroeng@att.net
Date: 9/15/03 8:12 PM Eastern Daylight Time
Message-id:
%zs9b.143502$3o3.10289900@bgtnsc05-news.ops.worldnet.att.net

Hi Folks,

I have a Pioneer SX 1250 Reciever that is giving me problems. It shuts
down
after about 30 minutes and the right heatsink seems warmer than the left.
I
have the service manual and have run a few tests but thought I might ask
around before I spend the next couple of days fighting this
one......thanks
for any help....Ross


If it plays normally otherwise, I'd bet it's a bias problem. The carbon
trimmers they use to set bias are pure garbage, and they'll drift just
looking
at them. There might be two adjustments per channel on this model. Flush
them
out with a quality cleaner, and see if they set up normally. If so,
replace
the pure garbage pots with mere crappy ones (one grade up and re adjust
the
bias.


John Del
Wolcott, CT

"Nothing is so opportune for tyrants as a people tired of its liberty."
Alan Keyes

(remove S for email reply)

 

[Ivanhoismine]

I have a bunch of these cables. I can put one in a USPS Priority mail envelope
and send them for $10. Let me know.

 

[Fishhead]

Thanks for the helpful tips!
It ended up being the convergence amps. When I reassembled the unit, I
forgot a plug. **DOH!!** The set works great now!!
Brad
"David" <dkuhajda@locl.net> wrote in message
news:68f82f5b.0309121343.5f7f367c@posting.google.com ...

The set is in protect shutdown and you need to take special precautions
prior to attempting the troubleshooting of the failure.
Things I have seen cause this failure:
1. Corrupted eeprom data. ******
2. lock up on clock or data lines, especially in the tuner.
3. blown audio output ic
4. failure on the dpc circuit board, increased resistor value or pin
circuit problem. ****
5. convergence output failure *****
6. digital convergence module failure, for those with it, also d/a
converter failure on those without the full module
7. shorted yoke windings ******
8. arcing high voltage cap ******
9. high voltage splitter
10. failed picture tube, shorted ****
11. vertical output ic failure *****
12. high voltage regulator op-amp
13. switch mode power supply regulation failure
14. flyback
The ones with the extra stars are the failures I see more often than the
others.
David

"Fishhead" <none@not.com> wrote in message
news:<bjsrgj01hdc@enews4.newsguy.com>...
Toshiba RPTV Dead. Power Light Blinks But Set Won'T Fully Power Up.The
set
acts like its going to powerup, then clicks off.Replaced convergence
amps
(Stk392-110). No help. I did find a possible open winding in T862.Any
other
ideas??Thank for any help,Bradcasiasb@sbcglobal.net

 

[Tardz]

Hi, I check chassis model and it is the same number. It is possible for me
to download from alt.binaries.schematics.electronic with Free agent V1.93.
If you have PDF writer, it is possible to divide in 2 or 3 parts (below 5
Meg) and use email to send files. Thank a lot.

yves_tardif@videotron.ca


"JW" <none@dev.nul> a écrit dans le message de
news:uf6hmvkc8j5a22shb38fodfmt4utn2r00r@4ax.com...

On Wed, 17 Sep 2003 09:25:27 -0400 "Tardz" <yves_tardif@videotron.ca
wrote in Message id: <QhZ9b.54665$LR.737721@wagner.videotron.net>:

Hi I have GS-790 monitor and I'm interested to have a copy of this
manual,
it is possible to repost it and where can I download it. Thanks.

Sure. Keep in mind that it's only good for chassis #VCDTS21528-1, and
there was more than one chassis number for this model. Check the number on
the back, and verify. If it's the same, I will post it in either
alt.binaries.e-book.technical or alt.binaries.schematics.electronic. Let
me know which group your server carries so you can retrieve it. If your
server doesn't have either one, I'm open to suggestions on where you want
it posted. FYI, It's 10MB.

Let me know.

 

[JW]

On Wed, 17 Sep 2003 19:23:42 -0400 "Tardz" <yves_tardif@videotron.ca>
wrote in Message id: <C16ab.60246$LR.848140@wagner.videotron.net>:

Hi, I check chassis model and it is the same number. It is possible for me
to download from alt.binaries.schematics.electronic with Free agent V1.93.
If you have PDF writer, it is possible to divide in 2 or 3 parts (below 5
Meg) and use email to send files. Thank a lot.

yves_tardif@videotron.ca

Done. I posted it in alt.binaries.schematics.electronic with the subject
"ATTN: Tardz - your here's your request."

 

[Jeeters]

This thread died and was buried over month ago. Get in the time machine!
And did you have to repost the entire thing? All that will do will restart
the thread.

"gothika" <gothika@earthlink.net> wrote in message
news:br5gmv0bgj1mrv30lbgr6cdll97sj5cpfr@4ax.com...

On Tue, 5 Aug 2003 14:42:33 +0000 (UTC), "Dave D"
someone@somewhere.com> wrote:
This isa forum for factual exchange of information not bad "jokes".
Try reading the forum title before posting crappy jokes.
Or better yet go find a forum with humor or jokes in it's title.
Most who come to this forum are here for serious pursuits.

<<<SNIP>>>

 

[gothika]

On Thu, 18 Sep 2003 09:34:35 -0400, "Jeeters" <noham@nospam.com>
wrote:

Sorry. I don't come to this groups very often and was a little to
tranked the other night to notice the date of the thread.

This thread died and was buried over month ago. Get in the time machine!
And did you have to repost the entire thing? All that will do will restart
the thread.

"gothika" <gothika@earthlink.net> wrote in message
news:br5gmv0bgj1mrv30lbgr6cdll97sj5cpfr@4ax.com...
On Tue, 5 Aug 2003 14:42:33 +0000 (UTC), "Dave D"
someone@somewhere.com> wrote:
This isa forum for factual exchange of information not bad "jokes".
Try reading the forum title before posting crappy jokes.
Or better yet go find a forum with humor or jokes in it's title.
Most who come to this forum are here for serious pursuits.

SNIP

 

[Sam Goldwasser]

"Licensed to Quill" <vintagepen@compuserve.nospam.com> writes:

I have an ES4000 shaver and some ES 8000 units all of which use magnetic
induction base-unit chargers

But I do not have a charger to the 4000. SO I tried putting it on the base
for the Linear ES 8000 units and cant understand why it wont work. Surely
magnetic induction is magnetic induction is magnetic induction and the
values of these units cant be all that different?

Does anyone know how I can get the unit to charge or is there some
relationship between the position of the base and the two arms at the top?
(the 4000 is substantially thinner than the 8000) but Panasonic makes the
new charger prohibitively expensive just to see if my units works

Difference in frequency, size of core pieces, voltage/current in coil, etc.

--- sam | Sci.Electronics.Repair FAQ Home Page: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Site Info: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: The email address in this message header may no longer work. To
contact me, please use the Feedback Form at repairfaq.org. Thanks.

 

[Sam Goldwasser]

"Duc" <Duci99@cs.com> writes:

On my ViewSonic 17PS the picture on the screen started kind of vibrating
until it went black with only a 1/4" wide vertical line in the middle of the
screen.

Is there a simple way I can check if the CRT or any other part has a defect?

It's not the CRT.

--- sam | Sci.Electronics.Repair FAQ Home Page: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Site Info: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: The email address in this message header may no longer work. To
contact me, please use the Feedback Form at repairfaq.org. Thanks.

 

[Max Volume]

In article <TsydnbZPOff5KfSiRVn-hw@giganews.com>, Jeeters
<noham@nospam.com> wrote:

This thread died and was buried over month ago. Get in the time machine!

I am accepting donations on behalf of the family of this thread. This
is not a scam whereby I take all the donations and jet off to Rio, this
is real. Please send all donations to:

"Killer DVD Player" Thread Memorial Fund
Behind The Hot Water Pipes
Third Washroom Along
Victoria Station

 

[Tardz]

Hi, sorry I have 2 parts on 24, I 'm not able to see document. I checked
that when I came back from work today. If you repost that, send me a email I
will retry to download. Thanks.

"JW" <none@dev.nul> a écrit dans le message de
news:uf6hmvkc8j5a22shb38fodfmt4utn2r00r@4ax.com...

On Wed, 17 Sep 2003 09:25:27 -0400 "Tardz" <yves_tardif@videotron.ca
wrote in Message id: <QhZ9b.54665$LR.737721@wagner.videotron.net>:

Hi I have GS-790 monitor and I'm interested to have a copy of this
manual,
it is possible to repost it and where can I download it. Thanks.

Sure. Keep in mind that it's only good for chassis #VCDTS21528-1, and
there was more than one chassis number for this model. Check the number on
the back, and verify. If it's the same, I will post it in either
alt.binaries.e-book.technical or alt.binaries.schematics.electronic. Let
me know which group your server carries so you can retrieve it. If your
server doesn't have either one, I'm open to suggestions on where you want
it posted. FYI, It's 10MB.

Let me know.

 

[JW]

On Thu, 18 Sep 2003 22:50:39 -0400 "Tardz" <yves_tardif@videotron.ca>
wrote in Message id: <6auab.7876$zL3.188691@wagner.videotron.net>:

Hi, sorry I have 2 parts on 24, I 'm not able to see document. I checked
that when I came back from work today. If you repost that, send me a email I
will retry to download. Thanks.

Hmm. Perhaps your binary server isn't so good. OK, I'll use Winrar and
split it into (4) 2.5MB parts, then email it. You'll need Winrar version
3.20 or higher to uncompress the file. I'll send the first two files and
wait for an acknowledgement from you before sending the second two. If I
get your ack before noon EST today I'll be able to send you the second two
parts; otherwise, I won't be able to send them till Monday. How does that
work for you?

 

[Tardz]

Hi and thanks, this is correct for me. Yesterday I had lot of problem with
my email server but now is ok. Thanks again et I will send you feedback
when I will receive first parts. Thanks again.


"JW" <none@dev.nul> a écrit dans le message de
news:ktklmvg4tt1h580of5ve7s9a42vo5k2li4@4ax.com...

On Thu, 18 Sep 2003 22:50:39 -0400 "Tardz" <yves_tardif@videotron.ca
wrote in Message id: <6auab.7876$zL3.188691@wagner.videotron.net>:

Hi, sorry I have 2 parts on 24, I 'm not able to see document. I checked
that when I came back from work today. If you repost that, send me a
email I
will retry to download. Thanks.

Hmm. Perhaps your binary server isn't so good. OK, I'll use Winrar and
split it into (4) 2.5MB parts, then email it. You'll need Winrar version
3.20 or higher to uncompress the file. I'll send the first two files and
wait for an acknowledgement from you before sending the second two. If I
get your ack before noon EST today I'll be able to send you the second two
parts; otherwise, I won't be able to send them till Monday. How does that
work for you?

 

[Nadir]

I replaced the STK regulator and all of the electrolytic caps (most
were marginal) in the power supply and horizontal section. This
helped a little but not a lot. I decided to run the set for a while
hoping the bad part would fail completely. After 4 hours I removed
the board again. By chance I noticed that C4407K 47nF@400V was hot.
I hed measured it when I first worked on the set and its value was
dead on. I took it out and measured it again and it was open circuit.
I replaced it with a 630V cap and the CR4403K 243636 diode. The set
runs fine now. After cooling for an hour I measured the cap again and
it was about 43nF, so obviously it was failing under load but would
measure fine once it had cooled down.
zen_nadir@hotmail.com (Nadir) wrote in message news:<4dde1835.0309152229.55604df3@posting.google.com>...

I am currently working on an RCA 27" model F27634ET, chassis CTC187BJ.
The original problem was the set would squeal when plugged in and
wouldn't power on. Q401 was shorted B-E, I don't have a BUH517 on
hand so I subbed with a BU2520DF. C4709 was also replaced and I
resoldered the flyback, STK regulator, H-Out transformer and pretty
much most of the deflection/PS section of the board. The set now runs
and the HOT is warm to the touch but well below maximum temperature.
However the picutre changes size dramatically with any change in
brightness. If I turn the brightness down low the picture will shrink
down by about 20% on all sides and there is some pincushion
distortion. I suspected it may be the usual tuner solder problem but
if i bring up a static picture and firmly tap the tuner the picture
doesn't flinch. Pincushion problems are usually related to Q851,
D851, C4803, C4402, C4403, CR4402, C4407 and CR4403 but here they all
test OK. I suspect it may be the STK regulator module failing but I
want to be sure before replacing it. Any help is appreciated.
Thanks.

 

[Al Savage]

On Wed, 17 Sep 2003 04:39:49 UTC, captainvideo462002@yahoo.com (Lenny)
wrote:

It has no B+ to the Hor. output. I hear the
smps squeal when it turns on and the green power led lights so I feel
that the problem might be as simple as B+ distribution but I can't
trace it.

I don't recall that harness length made these particularly difficult to
work with.

I don't have any notes on the 732, but I used to get a fair number of
738s across the bench. Don't know if they're similar. For the 738:

* Bad solder on power connector P102 on PS board.

* Ck. D213, C241, Q216.

* HOT shorted, then replace:
C215 100uf 16v
C226 47uf 35v
C237 47uf 25v

--
Regards,
Al S.

 

[ug]

ok, but expensive