Toshiba TV29C90 problem; Image fades to black...

[James Sweet]

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 !

What electrolytic capacitor affects the focus, though? I'll admit it's
been awhile since I've been inside a TV, however...

I suppose it could be one that affects the HV regulation.

 

[Ken Weitzel]

aaronep@pacbell.net wrote:

Hi Ken: The appearance of the screen when first turned on is more like
a kaleidescopy without any defined image. I don't know whether to
describe this as "bleeding" or "burned out whites". best, Aaron

Hi Aaronep...

OK. my guess was off, but just for your interest...

Bleeding would be when you see a picture of for instance
someone wearing a red shirt, and the red shirt appears to
be 'leaking or smearing red' to the right side of where
the shirt really is...

And burned out refers to for instance a pic of someone
wearing a white (or brightly colored) shirt, when it
all appears to be one mass. No shades in the shadows
where folds are, and so on...

Back to the electrolytics...

Take care.

Ken

 

[none]

On Sat, 02 Jul 2005 23:49:44 GMT, "James Sweet"
<jamessweet@hotmail.com> wrote:

"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.

The little white o-ring is the needle seal. It goes up in the needle

well.
If you look up in the needle well wth a flashlight you'll see the old
seal.(It'll be stained a yellow-brown color from the gas.)
Yo can pry it out with a small right angle dental pick or a slotted
jeweler's screwdriver. alternately you can also get it out by shooting
compressed air through the fuel supply inlet, should pop right out.
Press the new seal in using a dowel or punch the same diameter as the
seal. A bit of fine machine oil can be used to lubricate it to make it
slide in easier.. Be sure it seats firmly in place.
Test the needle to seat action before reassembling the carb to avoid
flooding out the mower.

You say it didn't last long. Did it just quit after running for awhile
or did it try to start and then die out?
The next thing that could be a problem is the primer bulb.
Depending on the model it could either of three different type priner
bulbs.(The carbuerator draws part of the suction required to pull gas
from the bowl through the primer bulb ports. If the bulb is rotten or
has a puncture it'll cause suction loss.)
A visual inspection on the bulb will usually tell. It'll be cracked or
split or be "gummy" when you squeeze it.
It's easy to replace and doesn't cost but 3-4 bucks.(Sears or parts
store.)
It'll be either the round non vented bulb, black, red or orange in
color or the accordian style that comes in either non-vented or
vented.( will have a small 1-2mm hole in the center of the bulb.)
All are held in by a circular spring clip. It has 5 or so square tabs
that stick out to grab the primer bulb well walls.
It can be prized out using a small slotted blade screwdriver, either a
#0 ot a narrow slot #1 blade.(jeweler's driver will work as well.)
Spray the whole spring and housing with a bit spray oil to slick it up
a bit.
Prize under one of the tabs until it moves out a bit then mover onto
the next one going a bit at a time in a circular pattern until you get
it out completely. The bulb can then be pulled or prized out. don't
worry about damaging it, it's a toss off item and can't be fixed.
Clean out the well with a bit of carb cleaner spray and a stiff
bristle brush, wire bruch is fine. You can also scrape out the old
rubber with a screwdriver or dental pick.
To install the new bulb just place the bulb all the way in and press
in the new retainer clip with a small slotted screwdriver.
This is done by placing the tip of the screwdriver into the circular
depression in the ring and pressing a gently at different points of
the ring in a circular pattern untill the ring is all the way against
the lip of the primer bulb. Then gently but firmly press with the
screwdriver in the depression of the ring at the base of each of the
retaining tabs.
You can test for a firm seat and lock by simply pinching the tip of
the primer bulb between forefinger and thumb and giving it a gentle
tug.
If it pulls out the tabs on the retaining ring have been overstressed
and need to be bent out straight.(Sometimes they come from the factory
out of spec and won't form a tight fit on your particular carb
housing.)
If the original ring came out in one piece and didn't snap you canuse
that one.
However to retension a spring, new or old, you use a pair of needle
nose pliers and gently bend the tabs out a bit so that they'll fit
snugly down the bullb well on your carb. Just be careful as it is easy
to snap the ring itself overstressing the tabs.

Also ensure that all of the fine ports on the carb are clean. This
includes the small hole on the lower side of the primary jet well.(The
well that the brass jet/bowl screw screws into.)
Also the brass bowl retaining screw depending on the model also has
one or two small ports on it that need to be clean for fuel to get to
the main supply port.
The short screw has one, the taller screws have two, 180 degrees
opposed at the base of the screw.(just under the hex head.)
You can use an aerosol carb spray to clean them out. I use either the
High-Tech brand from Wal-Mart, The store brand from Autozone or a good
name brand like Justice Brothers Carb spray. Anything that is acetone
base is good. Avoid Gumout carb spray, worst stuff made.
Most all come with a red plastic pipette for blasting out fine ports,
use it.
If the clog is stubborn spray some cleaner in a small cup and soak the
parts to soften the clog up.(I use the plastic cap that comes on the
spray can.)
If the ports won't unclog using the cleaner take a small piece of
stiff wire.( I use a piece of copper strand from a piece stranded
automotive wiring 18 gauge or whatever.)
Gently push it through the clogged port to break up the tarred gunk,
follow with a healthy spray of cleaner.
Use the pipette and carb spray to back blow the ports in the main
intake of the carb also. This'll clean out the primary suction port
that runs through the welsh plug and the seconday that runs through
the primer bulb housing.
Let parts dry or blow off with compressed air, then reassemble carb.

 

[none]

On 2 Jul 2005 15:34:23 -0700, "spongehead" <hgoodale_msp@msn.com>
wrote:

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?

It's the bulb, gone bad. Easy to replace. See my reply to the other
posts on this subject.
Will be glad to assist with more details and if needed pics.

 

[Jamie]

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

could be, also could be a regulator problem or bad Picture tube.

--
Real Programmers Do things like this.
http://webpages.charter.net/jamie_5

 

[Jim Yanik]

"NSM" <nowrite@to.me> wrote in news:ZgWxe.105193$9A2.4019@edtnps89:

"Jim Yanik" <jyanik@abuse.gov.> wrote in message
news:Xns968875EBCC7DEjyanikkuanet@129.250.170.84...

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

Well,then you are not just cleaning tarnish,you are reshaping eroded
contacts,an entirely DIFFERENT task.

I find it works for all cases.

N

IIRC,the OP wanted to clean off a PCB's tarnish.
I'd like to see you use your diamond file on a PCB for tarnish removal.

PS;the title of this thread is "BEST way to -clean- copper".

--
Jim Yanik
jyanik
at
kua.net

 

[Inty]

<rk73737@yahoo.com> ha scritto nel messaggio
news:1120437214.935427.308480@g47g2000cwa.googlegroups.com...

Sam,
You seem like a smart guy. I wonder if you might have an answer to this
problem:

If you want to talk to Sam Goldwasser why didn't email he ? Why did you
waste bandwidth ? This is an *electronics* newsgroup, not an *economic*
newsgroup.

I.

 

[Inty]

"larry moe 'n curly" <larrymoencurly@my-deja.com> ha scritto nel messaggio
news:1120424782.845056.231760@o13g2000cwo.googlegroups.com...

I'm sure the erasure was caused by NEC's Windows-based flash program
for their ND-2500A DVD writer because when I ran UniFlash to hot flash
the mobo BIOS chip, I had the chip's contents written to a file, and
that file looks like the NEC DVD writer's BIOS. The DVD writer did get
updated though.

Why did you flash any bios via Windows ? Why didn't you flash via a boot
disk with DOS, UNIFLASH and the relative .BIN fiel ?

I.

 

[Inty]

<boese.c@maplan.com> ha scritto nel messaggio
news:1120356200.608395.289120@g43g2000cwa.googlegroups.com...

decent, not preferct, but not too bad. My question is does this sound
like the HVT?

HVT, CRT Narrow Socket and CRT are the most probably causes.

I.

(sorry for the poor english ;-))

 

[NSM]

"Jim Yanik" <jyanik@abuse.gov.> wrote in message
news:Xns9688D391651E4jyanikkuanet@129.250.170.85...

IIRC,the OP wanted to clean off a PCB's tarnish.
I'd like to see you use your diamond file on a PCB for tarnish removal.

But the topic drifted to "hi current contacts"

For PCBs I'd use an acid.

N

 

[Mark D. Zacharias]

"Inty" <inty.the.best@email.it> wrote in message
news:6WWxe.29538$h5.1344146@news3.tin.it...

"Telly" <tchm@uiuc.edu> ha scritto nel messaggio
news:1120401426.731391.283260@g47g2000cwa.googlegroups.com...

May I bother you with one more question? Does an online manual
for this VCR or equivalent exist anywhere? The power supply of the
PV-4760 seems hard to get to, and I do not want to damage something
while trying to fix the erratic display problem.

Do not change the whole psu. Change only electrolyitic caps in the
secondary
part !

I.

And the 4.7uF (10 uF on some models) in the primary side.

Mark Z.

 

[Ron(UK)]

NSM wrote:

"Jim Yanik" <jyanik@abuse.gov.> wrote in message
news:Xns9688D391651E4jyanikkuanet@129.250.170.85...


IIRC,the OP wanted to clean off a PCB's tarnish.
I'd like to see you use your diamond file on a PCB for tarnish removal.


But the topic drifted to "hi current contacts"

For PCBs I'd use an acid.

N

Lemon juice works fine.

Ron (UK)

--

www.lunevalleyaudio.com

 

[JazzMan]

Inty wrote:

rk73737@yahoo.com> ha scritto nel messaggio
news:1120437214.935427.308480@g47g2000cwa.googlegroups.com...
Sam,
You seem like a smart guy. I wonder if you might have an answer to this
problem:

If you want to talk to Sam Goldwasser why didn't email he ? Why did you
waste bandwidth ? This is an *electronics* newsgroup, not an *economic*
newsgroup.

I.

He was just trying to start an argument, he's a troll. Just
ignore him, he'll go away as soon as he realizes there's nobody
here that wants to spank his monkey.

JazzMan
--
**********************************************************
Please reply to jsavage"at"airmail.net.
Curse those darned bulk e-mailers!
**********************************************************
"Rats and roaches live by competition under the laws of
supply and demand. It is the privilege of human beings to
live under the laws of justice and mercy." - Wendell Berry
**********************************************************

 

[Inty]

"JazzMan" <No_Spam@airmail.net> ha scritto nel messaggio
news:42C93767.2EA5@airmail.net...

He was just trying to start an argument, he's a troll. Just
ignore him, he'll go away as soon as he realizes there's nobody
here that wants to spank his monkey.

Ah, ok.

I.

 

[Inty]

<rejeannad@hotmail.com> ha scritto nel messaggio
news:1120489667.318558.54260@f14g2000cwb.googlegroups.com...

I have replace Q404 (horizontal output)the set has work fine for about
30 minutes and the transistor blown again, i have check all capacitor
and they test ok, the B+ is ok.
Does anyone have any tips on this set.

Driving electrolytic, feedback polyester caps connected to HOT.

I.

 

[Jim Adney]

On 3 Jul 2005 09:22:27 -0700 "js5895" <JoshTmp@nycap.rr.com> wrote:

My stove oven's thermostat bulb broke off, I went to
a parts store and they said I cant buy just the bulb
but, I have to buy the whole part, the thermostat with
bulb. Is this true?

I think the answer is yes, you have to replace the whole thing.

I had a similar experience with an oven controller and also found that
no parts were sold, only complete assemblies. The part that broke on
mine was the little ceramic thermal relay, and the repair shop told me
that this was the part that always broke. That part alone should have
cost only $10 to replace (and that part is identical on all pre solid
state controllers) but I was still forced to buy the $70 assembly.

If you were patient and lucky you might find someone with a bad
controller and a good thermostat bulb sub-assembly, but that's an
extreme long shot.

-
-----------------------------------------------
Jim Adney jadney@vwtype3.org
Madison, WI 53711 USA
-----------------------------------------------

 

[Art]

Possible HV Block or Convergence power Supply. Post what actual diagnostics
you have done.
"pink" <dapinkie@gmail.com> wrote in message
news:1120495196.199568.16140@g49g2000cwa.googlegroups.com...

I have an RCA rear projection TV P46725SK - set is plugged in and was
working fine until today when I tried to turn it on. I can hear a
faint "click click click" from the vicinity of the flyback transformer
when the power button is pressed. The power light blinks in unison
with the clicking sound. I'd like to fix this puppy since I don't have
the cash for a new TV right now and it's so heavy I dread getting it
out of the house. Help!

 

[dig154]

.... and it will continue to happen all the time. Not a damn thing you can do
about it.

<dkuhajda@locl.net> wrote in message
news:1120499497.577705.6160@f14g2000cwb.googlegroups.com...

> This happens ALL the time.

 

[Inty]

"dfwjas" <dfwjas@gmail.com> ha scritto nel messaggio
news:1120489057.230715.190820@f14g2000cwb.googlegroups.com...

I am trying to make a case for repairing the TV vs using the money
towards the purchase of a new TV in the next 6 months.

Really did you want to swap a tv that's 4 year's old and has only remote
problems ? If you can't fix it or can't get it repaired, use it without
remote ;-)

I.

 

[NSM]

"Jim Adney" <jadney@vwtype3.org> wrote in message
news:5elic1lmfj86qrju84cp0eb3dvtn2f2frt@4ax.com...

If you were patient and lucky you might find someone with a bad
controller and a good thermostat bulb sub-assembly, but that's an
extreme long shot.

We'll all be cooking with phasors before that happens.

N