Toshiba TV29C90 problem; Image fades to black...

In sci.electronics.repair Searcher7@mail.con2.com wrote:

You know, you speculate, imagine, and assume way too much...

You left room for that ;-) allthough I did enjoy and appreciate your
explanation. Sounds like an interestig project, so good luck!

---
Met vriendelijke groet,

Maarten Bakker.

 

[Art]

May need to change the DCU as a complete item, then obtain an overlay for
the set to proceed with a complete registration adjustment.
<ZZactly@aol.com> wrote in message
news:1120266922.035244.163730@o13g2000cwo.googlegroups.com...

Hi;

I Tshot it for the usual convergence job, had the usual bow which is
characteristic for this failure in sets that use convergence for T/B
pin correction.

The other guy changed the ICs, and one resistor. Now the convergence is
really whacked out. Looking at it I know why the ICs went, they are
being driven with some totally whacked out waveform. What is obvious is
that the convergence data are screwed up, I mean if you ever did acid a
crosshatch on it might result in a flashback. It's funny, but this
thing is so whacked out it is almost artistic ! If we wind up replacing
the DCM I want the old one. Actually I would only need the EPROM, put
some water cooling on the STKs and build it into my wall. I'd take the
whole set but I guess I would have to buy the customer a set, minus the
repair cost. I might make due on the $6 EPROM if I ever even do this.

I can tell that all six channels are working, and I can tell the DCM is
feeding it, and the only way for this particular error to happen is
corrupt data.

Is there a procedure on board that I can do to reset the data to
pre-factory alignment values ? I'm not afraid to do a full alignment,
even on the whole set, but the service manual isn't very clear on this.

If I lose the option data, especially if the procedure doesn't reset
the convergence data this would not be good. Actually it would be quite
difficult to even read the option data to write it down.

EPROMs just screw up sometimes, we've seen this in RCAs, when you don't
bother to replace it, just re-initialize it.

Does the procedure exist on this set ?

Thanks in advance.

JURB

 

[Tom MacIntyre]

On 1 Jul 2005 16:46:18 -0700, sidneybek@yahoo.com wrote:

20" Goldstar tv model:CN-20B90,chassis:NC-4JA,year:Sept 1995,CSA File
no:LR80622.I need the part # for R811=180 ohm,25w (ceramic stand up) as
I could use these on the tv's listed below:

Why not this?

http://mcm.newark.com/NewarkWebCommerce/mcm/en_US/endecaSearch/partDetail.jsp?SKU=25W118&N=0

If they are not stand-up, use the stand-up shell of the originals to
make them so.

Tom (fellow Bluenoser, to the NNE of you in Cape Breton)

To know why I need one you can read below:

We in the past several years have noticed alot of those cheap 25" Orion
chassis tv's come into our repair shops with a domino effect of failed
parts due to a high ESR C446=1 Uf,160v=horizontal driver transformer
cap.The value of R506 and a part # seems to be a popular issue well the
value is 180 ohm,20 watt cement and I finally found a part #:

Panasonic # ERF20ZJ181
Orion # R5W2CH181J

Or you can try using:

150 ohm,20w=Sony # 1-205-938-11

For more info on what I am talking about read below:

25" Durabrand stereo tv modelBTV2500,chassis:M3I05,year:Oct
2000,UL:289X=Orion.Howard W.Sams # 4430.The customer turned it on one
day and it shut off.Upon inspection I discovered the following to be
defective:

C446=1 uf,160v=horizontal driver transformer cap=high ESR
Q401=2SD2499=HOT transistor (shorted)
R506=180 ohm,20 watt (open)= Orion # R5W2CH181J (cement)= 25W power
wirewound resistor NTE # 25W118
=Panasonic # ERF20ZJ181 or you can try using a 150 ohm,20w Sony #
1-205-938-11
R515=1.5 ohm,3 watt (metal)=Orion # R3X28B1R5J NTE # 3W1D5 (feedback
from pin 3=input & pin 4=output of IC501=STR30110) (open)=Orion #
R3X28B1R5J (metal)
IC501=STR30110=pins 3 (input) & pins 4 (output) are shorted

This tv uses the following parts:

FB401=Flyback # FCM-25C001 (Samsung) or 3225010 (Emerson)
Yoke # 7M062505
RCA crt # 63AHC26X

This set is the same as a Memorex MT2251,so you can go to the Memorex
site and download the Service Manual.This set is similar to
Orion/Sansui TV2520 and TVM2515 and the service manuals can be download
free at:

http://www.schematicsforfree.mattsoft.net
http://www.memorex.com
http://ads.hopperinc.com/form/product_search/search.asp?t=1
http://www.memorexelectronics.com

search on Google using those models I discovered that some of the
brands listed below also use that Orion chassis:

Orion
Admiral
Memorex
Sansui
Citizen

Sidney
Dartmouth,Nova Scotia
Canada

 

[Tom MacIntyre]

On 2 Jul 2005 08:00:43 -0700, aaronep@pacbell.net wrote:

I have 7 year old 5 inch GE Color Tv set.Model #05GP008. When I turn
it on in the a.m. , the picture is blurry and un-viewable. However,
after approx 20 minutes the picture improves and is viewable.

Any suggestions on what I might do to return to normal operation?

best, Aaron

It sounds like a capacitor issue, but...that being said, the CRT is
also a capacitor of sorts. That is at least a possibility, and the FBT
as well could cause this problem.

My approach to this would probably be to set the alarm clock 20
minutes early.

Tom

 

[kip]

WE HEAR YOU>>

"Ray" <rcgagnon@mts.net> wrote in message
news:1120317241.801434.27690@f14g2000cwb.googlegroups.com...

DOES ANYBODY OUT THER HAVE THE FIRST 1998 FIXFINDER DISC I HAVE LOST
MY WHEN MY OLD HARDDRIVE CRASHED UP AND CANNOT RECOVER IT ALSO I
CANNOT
FIND MY DISC. I HAVE ALOT OF RCA COLOR TVS VCR DVD ARE THE DISC BUT
I NEED THE FIXFINDER98 TO RUN THEM.

THANK YOU RAYMOND

 

[Inty]

"Tom MacIntyre" <tom__macintyre@hotmail.com> ha scritto nel messaggio
news:5abdc15ojsfoc475vd43cjmrv64k7eucvr@4ax.com...

It sounds like a capacitor issue, but...that being said, the CRT is
also a capacitor of sorts. That is at least a possibility, and the FBT
as well could cause this problem.

Nah, I think that's a failing electrolytic that works only when hot I
suggest to open the little tv and flow hot air onto the board : if the TV
works immediately, it's a failing capacitors. Because in a too small tv
there are circa 10-15 caps I suggest to change all electrolytic in the
built-in power supply and deflection circuit. Try also failing electrolytics
in the color "jungle" circuitry, and try also the tunner !

My approach to this would probably be to set the alarm clock 20
minutes early.

Fun ! But this can damage the TV !

I.

 

[Inty]

<dkuhajda@locl.net> ha scritto nel messaggio
news:1120314156.234132.10090@f14g2000cwb.googlegroups.com...

That just does not make any sense. Orion is known for some of the
lowest quality and lowest priced junk already, why would anyone bother

All the ORION tubes that i had over 10-15 years !

trying to sell under that name? Like they would make much money doing
that scam?

I don't really know, but those clones are unexpensive and have an horrible
picture, they are good only for cannibalization ;-)

It is more likely that Orion like the rest of the junk brands listed,
is now just a name that has been sold several times over to the highest
bidder.

Maybe someone used Orion brand to sell factory-damaged products, i.e. those
Gx05 seem Philips because they use only Philips components, have four number
component numeration, but haven't any Philips brand... it maybe a Philips
damaged set... also the front panel seems to be Formenti/SchaubLorenz/Selčco
!!! It maybe a mixture of junked defective products sold by someone using
Orion brand...

I.

 

[Inty]

"Telly" <tchm@uiuc.edu> ha scritto nel messaggio
news:1120324667.891844.296570@g49g2000cwa.googlegroups.com...

Panasonic PV-4760
I read somewhere that the cause of this problem may be a "transistor
C4130 (NTE 2312) 330 uf caps, 22uf cap", but I do not have a clue of
what any of these numbers/letters mean or where to find that part in
the
VCR. I trust that somebody in this forum can help.

They are the famous failing electrolytic caps in the Panasonic VTR PSUs.
Change all electrolytic capacitors in the power supply, this will fix your
problem !!!

I.

 

[jay]

I had a GE 5" TV with a similar problem. I took it to a repair place who
fixed it but the problem came back a week or two later, and then a 2nd
attempt didn't fix it permanently either, so they gave up and refunded my
money.

J.

 

[NSM]

"Anand" <ardhuru@vsnl.com> wrote in message
news:1120307225.171654.213500@g49g2000cwa.googlegroups.com...

I had heard of a technique involving putting the PCB in an oven to
solve these kinds of intermittent problems.

Last resort surely. I know Dell is crap for warranty, but have you asked
them?

N

 

[NSM]

"Alan the Tech" <mymail@is_a_secret.com> wrote in message
news:jmmdc1924mhe5c4qmnfkj3770hakv82q78@4ax.com...

You also can use Brasso. I use it on hi current contacts on the job.

I like a diamond nail file for those.

N

 

[NSM]

"Anand" <ardhuru@vsnl.com> wrote in message
news:1120329958.046105.265240@g43g2000cwa.googlegroups.com...

The notebook is over 4 years old. I dont think Dell would honour the
warranty. Even more so as it is pretty obvious that I have dismantled
the notebook a number of times.

I'd still ask. It may be a fault they're aware of.

N

 

[Jim Yanik]

"NSM" <nowrite@to.me> wrote in news:LcBxe.126867$on1.100884@clgrps13:

"Alan the Tech" <mymail@is_a_secret.com> wrote in message
news:jmmdc1924mhe5c4qmnfkj3770hakv82q78@4ax.com...

You also can use Brasso. I use it on hi current contacts on the job.

I like a diamond nail file for those.

N

you probably remove a lot more material with the file than with a
chemical(polish) like Brasso or Tarn-X.
Tarn-X is even easier to use than Brasso.

--
Jim Yanik
jyanik
at
kua.net

 

[James Sweet]

"spongehead" <hgoodale_msp@msn.com> wrote in message
news:1120343663.281037.37890@f14g2000cwb.googlegroups.com...

I got the needle at a local repair guy for 2 bucks. Came with needle,
clip and some liitle white gasket looking thing. The white thing didnt
quite fit anywhere so I left it out. Put everything together and it
started right up but didnt last long. I have to keep pushing the bulb
to keep it going. Is it because of the little white thing or am I
losing air somewhere?

Is this an engine with a float bowl carb? If so, remove the banjo bolt that
holds the bowl on and clean out the tiny passages in it, those clog easily.

 

[NSM]

"Jim Yanik" <jyanik@abuse.gov.> wrote in message
news:Xns9687C33BE88A8jyanikkuanet@129.250.170.83...

You also can use Brasso. I use it on hi current contacts on the job.

I like a diamond nail file for those.

you probably remove a lot more material with the file than with a
chemical(polish) like Brasso or Tarn-X.
Tarn-X is even easier to use than Brasso.

That's what I need. Sometimes silver points grow peaks and craters. A
diamond file in the hands of the skilled (me) works well.

N

 

[Sam Goldwasser]

none <Vampyres@nettaxi.com> writes:

On 28 Jun 2005 12:38:42 -0400, Sam Goldwasser <sam@saul.cis.upenn.edu
wrote:

"spongehead" <hgoodale_msp@msn.com> writes:

Not bad, was able to find it for 11 bucks. If you want to send pic of
linkage, just add "msp" after the underscore.
I did notice the spring was all stretched out, not sure how important
that is or if I can get away with stretching it some more.

Probably:

http://www.angelfire.com/mb2/visitme/mower/tecumseh.html

The spring is probably fine, that's the way it is.

--- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/
Repair | Main Table of Contents: http://repairfaq.ece.drexel.edu/REPAIR/
+Lasers | Sam's Laser FAQ: http://repairfaq.ece.drexel.edu/sam/lasersam.htm
| Mirror Sites: http://repairfaq.ece.drexel.edu/REPAIR/F_mirror.html

Note: These links are hopefully temporary until we can sort out the excessive
traffic on Repairfaq.org.

Important: Anything sent to the email address in the message header above is
ignored unless my full name is included in the subject line. Or, you can
contact me via the Feedback Form in the FAQs.

If you follow the diagrahms at that link you'll be installing the
govenor spring link BACKWARDS.
The short wire section of the link goes into the lower hole on the
govenor control arm not the spring.
Insert the wire through the front of the hole and the spring goes onto
the throttle link arm on the throttle plate assembly.

Functionally, they are equivalent. The only issue is whether parts
interfere. There have been all sorts of arrangements depending on model.
The important thing is that the solid wire goes between the governer lever
and throttle plate on the carb. The spring'd wire goes between the governor
lever and throttle control (or fixed location if non-adjustable).
And, yes, which hole in the governer lever are used for each matter!

--- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/
Repair | Main Table of Contents: http://repairfaq.ece.drexel.edu/REPAIR/
+Lasers | Sam's Laser FAQ: http://repairfaq.ece.drexel.edu/sam/lasersam.htm
| Mirror Sites: http://repairfaq.ece.drexel.edu/REPAIR/F_mirror.html

Note: These links are hopefully temporary until we can sort out the excessive
traffic on Repairfaq.org.

Important: Anything sent to the email address in the message header above is
ignored unless my full name is included in the subject line. Or, you can
contact me via the Feedback Form in the FAQs.

 

[Alan the Tech]

On Sun, 03 Jul 2005 01:32:34 GMT, "NSM" <nowrite@to.me> wrote:

"Jim Yanik" <jyanik@abuse.gov.> wrote in message
news:Xns9687C33BE88A8jyanikkuanet@129.250.170.83...

You also can use Brasso. I use it on hi current contacts on the job.

I like a diamond nail file for those.
A diamond file may be ok for what you do, but when I say hi current

I'm talking 12 to 16 power modules with 2200 amps coming from each
into a common buss line. with a combined current of 26400 to 35200
amps. Start taking material off the contacts and your talking some
real fireworks if you don't weld everything together. And at that
current levels a few mills of oxidation acts like a power resistor and
it gets real hot. I had a 3 inch X 5 inch X 1/2 inch thick contact
plate with just a little corrosion get hot enough to burn my hand. (I
got first degree burns that time) That was before I started to polish
the contacts.

you probably remove a lot more material with the file than with a
chemical(polish) like Brasso or Tarn-X.
Tarn-X is even easier to use than Brasso.
I haven't tried Tarn-X
That's what I need. Sometimes silver points grow peaks and craters. A
diamond file in the hands of the skilled (me) works well.

N

 

[Andy Cuffe]

On 2 Jul 2005 19:03:20 -0700, boese.c@maplan.com wrote:

OK, I posted a message a month or so ago, now I have a few more
questions. My JVC 32" TV turned whited and was out of focus. I took it
to a local shop, the said it was the High Voltage Transformer, but they
said they turned the focus all the way one way, and got a fairly good
picture. So I have been using the TV. When you first turn it on, it is
out of focus pretty bad, but after 15 minutes, the picture is faily
decent, not preferct, but not too bad. My question is does this sound
like the HVT?

Thanks

It sounds like the correct diagnosis to me. The only other
possibility is a bad CRT, but they usually aren't temperature
sensitive. If you're happy with the TV it's worth repairing. Do it
now before the flyback fails completely and damages other parts.
Andy Cuffe

baltimora@psu.edu <-- Use this address until 12/31/2005

acuffe@gmail.com <-- Use this address after 12/31/2005

 

[Inty]

"dfwjas" <dfwjas@gmail.com> ha scritto nel messaggio
news:1120356825.608177.296670@z14g2000cwz.googlegroups.com...

I feel that the problem is in the TV. Any ideas on how I can get this
problem fixed by my self or get it repaired.

Test the receiver, resolder reicever's solder and see with a scoop what
signal is going out. Also test if the reicever is powered ! If you don't
solve, change it, or try the uP !

I.

 

[Inty]

<cchomanics@cfl.rr.com> ha scritto nel messaggio
news:1120338346.880728.305770@o13g2000cwo.googlegroups.com...

I have A Mitsubishi TV Model CS26201. It shuts off after about 5-10
minutes. If I unplug it and plug it in again, it turns on for another
5 to 10 minutes then shuts down again. It will not turn back on if I
just push power. I have to unplug it and count to ten. What might
this be?

Defective heat-sensitive electrolytics ?

I.