Toshiba TV29C90 problem; Image fades to black...

[Peter Hofmann]

Searching for 1 or 2 pieces of integrated circuit device TDA 2655 B - tv
vertical deflection device.
My location is in Austria, Europe.
Please info - thanks in advance to
oe3pha@hotmail.com

 

[Jeff Wisnia]

Mark Zenier wrote:

In article <zLydnZVzrJEpLYfYnZ2dnUVZ_tWdnZ2d@conversent.net>,
Jeff Wisnia <jwisnia@conversent.net> wrote:
...

current draw would be so I grabbed one of the foglight assemblies and
connected it to the Eico 1050 battery charger/DC power supply which has
been part of my garage tool clutter for nearly 50 years:


Er, are you feeding a peak reading meter the unfiltered output of
a full wave rectifier?

Just dropped back in, and in response to your question, the EICO does
have a pretty large filter cap in it, though I can't testify to how many
of its microfarads may have grown legs and run away over the years.

However, the check I performed against my bench supply, which is
definitely well filtered, confirmed the ammeter's calibration error.


I got a few giggles reading some of the interchanges on this thread I
started, between "Homer J Simpson" and others.

I'm thinking that some of the participants' alimentary canals may have
somehow gotten completely reversed. Medical miricals, to be sure.

Jeff

--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
The speed of light is 1.8*10^12 furlongs per fortnight.

 

[Lostgallifreyan]

Jeff Wisnia <jwisnia@conversent.net> wrote in news:x9udnZ-VU-
M2Cs7YnZ2dnUVZ_tydnZ2d@conversent.net:

I'm thinking that some of the participants' alimentary canals may have
somehow gotten completely reversed.

That's been said to be even worse than it sounds. (House...)

 

[Rich the Newsgroup Wacko]

On Thu, 09 Nov 2006 16:03:46 -0500, Jeff Wisnia wrote:

I'm thinking that some of the participants' alimentary canals may have
somehow gotten completely reversed. Medical miricals, to be sure.

Sounds like a case of optical rectusis - when the optic nerve gets
scrambled with the nerve to the bowels.

It gives you a shitty outlook on life. ;-)

Cheers!
Rich

 

Say, can you tell me what that code means, specifically? Major
problem? Costly? Complicated? Worth the trouble?

I've inherited one of these 53" Sony bohemoths and have a problem with
it shutting off periodically. I get the incessant blink code, the
meaning of which is described below, and can occasionally get the
sucker fired back up after unplugging an replugging the power source.

gracias,
dekeus


Fastvale ha escrito:

"Bryan Hunter" <bryanehunter@hotmail.com> ha scritto nel messaggio
news:XDxVg.91672$PD.8911@fe2.news.blueyonder.co.uk...
Hi,
I switched this TV on today and after a few seconds the sound came on for
about 2 secs before there was a click like the TV had switched to standby
and the sound went off and no picture appeared. The standby light then
flashed continuously until the power was switched off.
This repeats each time it is switched on.



Continuous Blink Once A Second, No Pausing.
No reply from the jungle IC301 (data bus is busy, shorted to ground or held
high), IK video path is defective.

good luck!

 

[3T39]

Hello, Christopher!
You wrote on 13 Nov 2006 09:32:48 -0800:

CT> I recently bought a 2.1 mm DC line socket from Maplin (part no. JK11M)
CT> so I could power a project using a plug-in power adaptor (wall wart).
CT> Soldering a lead to the outer coaxial contact was no problem, but when
CT> I tried to solder a lead to the inner contact, the plastic insulation
CT> melted!

CT> I'm not a novice to soldering and I wasn't using an inappropriately
CT> large iron. The iron I was using is an Antex rated at 18 watts,
CT> although it isn't a regulated iron. I didn't touch the plastic
CT> insulation with the iron. The joint clearly didn't get hot enough to
CT> melt the solder, so I reckon the plastic must have melted at less than
CT> 180 deg. C.

CT> The Maplin socket design is bad in two ways. Firstly the insulator is
CT> made from a thermoplastic, and secondly the solder bucket for the inner
CT> contact is right next to the plastic insulator.

CT> So I have a few questions. Are all 2.1 mm line sockets like this or are
CT> there better designs out there? If there are better ones available,
CT> where can I get one from? And how are you supposed to solder these
CT> sockets with thermoplastic insulators?

CT> Suggestions would be appreciated.

CT> Best wishes,

If you have space, use of a small crock clip positioned just a little
downstream of the intended soldering point, can act as a heat sink and carry
some of the heat away, give yourself just enough free metal to make a quick
joint.

With best regards, 3T39. E-mail: rubbishrat@hotmail.com

 

Michael A. Terrell wrote:

"J. Todd" wrote:

Since warmer=drier, I might look for paper tubular
caps. When moist, they leak badly.

Paper capacitors? Transistor radios use electrolytic and mylar film
instead of paper, but the electrolytics were poor quality, and they
don't age very well. The capacitors in tuned circuits are either mica,
ceramic or polystyrene.

Lytic caps are easily tested by piggybacking. Just clip a similar value
cap on, no need for any soldering or cutting. But really its farily
pointless unless you do some fault finding first.


NT

 

[kyle]

James,

When you say "once IT starts to burn" .. what is IT? The blue filter?
What exactly?

I have a service guy coming out wednesday.. charging me $60 trip fee,
then $175 labor + parts.. ouch! I throw the tv away at $750 all
inclusive.. who knows what else might go wrong with it



James Sweet wrote:

kyle wrote:
Ohh PS- as last night was our first real long usage (+4hrs) of the
beast, it started to get worse! It is now taking up a considerable
more bottom right portion than when we first turned it on, verified it
was working / hooked up correctly to DVR, then turned it off...



That's expected, once it starts to burn, it darkens and absorbs light
which burns it faster.

 

[boardjunkie]

Arfa Daily wrote:

No DC offset on the audio up to the relay on either channel ? If there is
any, the protect circuit will inhibit the relay.

Arfa

Ahhh...good point. Yes, look for any DC at the output.

 

[Jim Land]

"3T39" <rubbishrat@hotmail.com> wrote in
news:4558e933$0$18053$db0fefd9@news.zen.co.uk:

Hello, Christopher!
You wrote on 13 Nov 2006 09:32:48 -0800:

CT> I recently bought a 2.1 mm DC line socket from Maplin (part no.
JK11M) CT> so I could power a project using a plug-in power adaptor
(wall wart). CT> Soldering a lead to the outer coaxial contact was no
problem, but when CT> I tried to solder a lead to the inner contact,
the plastic insulation CT> melted!

CT> I'm not a novice to soldering and I wasn't using an
inappropriately CT> large iron. The iron I was using is an Antex
rated at 18 watts, CT> although it isn't a regulated iron. I didn't
touch the plastic CT> insulation with the iron. The joint clearly
didn't get hot enough to CT> melt the solder, so I reckon the plastic
must have melted at less than CT> 180 deg. C.

CT> The Maplin socket design is bad in two ways. Firstly the
insulator is CT> made from a thermoplastic, and secondly the solder
bucket for the inner CT> contact is right next to the plastic
insulator.

CT> So I have a few questions. Are all 2.1 mm line sockets like this
or are CT> there better designs out there? If there are better ones
available, CT> where can I get one from? And how are you supposed to
solder these CT> sockets with thermoplastic insulators?

CT> Suggestions would be appreciated.

CT> Best wishes,

If you have space, use of a small crock clip positioned just a little
downstream of the intended soldering point, can act as a heat sink and
carry some of the heat away, give yourself just enough free metal to
make a quick joint.

Yes, a heat sink is a good idea, but as Christopher originally stated,
the point he is trying to solder is right next to the plastic that melts,
so there's no room for a clip.

The idea of inserting the mating connector probably provides a little
heat sink. If you want a larger one, try suspending the connector
(solder connection up) in a cup of water, so the water covers the
plastic, but the solder connection is out of the water. That should keep
the plastic cool while you solder. Just dry out the connector before you
use it.

 

[Ray]

Get a can Of "Cold Spray" when it is working good, gently spray each
transistor to find which one is causing the trouble. Then replace it with a
new germanium transistor.


<wrongaddress@att.net> wrote in message
news:1163387574.804150.266160@h54g2000cwb.googlegroups.com...

I have an old 8 gernamium transistor, protable AM radio that is noisy
on weak stations when cold. It works reasonably well when set it in the
sunshine and warms up. The problem seems to be the RF section since the
noise goes away when the volume is turned down. I'm suspecting the
germanium transistors may be the problem and wondering which one might
be replaced with a silicon variety to cure the temperature problems?

I'm not sure what all 8 transistors do. Two are in the output stage,
and another is used as a audio driver that drives the audio input
transformer.There are four RF coils, the usual oscillator (red) and
mixer (yellow) and white (1st IF) and (black (second IF). But that only
requires 6 transistors, and there are eight total. The detector is a
diode, so they didn't use a transistor for that. I haven't figured out
what the other 2 transistors do.

I'm thinking of replacing the oscillator transistor with a high gain
silicon variety to try and eliminate the temperature problems?

Any other ideas?

-Bill

 

[b]

haddon@gmail.com ha escrito:

lj_robins wrote:

haddon@gmail.com wrote:
I recently acquired a Sun GDM-90w10 (rebadged Sony w900) 24" widescreen
crt. It is very old (manufactured Dec '97), but it was in remarkably
good condition and worked beautifully.

Tonight I returned home and switched it on, to find that while it made
the clicking noises that it usually makes as it starts up, it didn't
come on. Instead of the tube powering up with the typical "bong" noise,
it made an extra click noise, and the green light switched off, to be
replaced by the light next to it blinking orange. This LED has a symbol
that appears to be a crossed out lightbulb.

When I bought the monitor, there were no manuals for it, and the best I
could find on the internet was a <a
href="http://www.sunshack.org/data/sh/2.0/infoserver.central/data/syshbk/Devices/Monitor/MONITOR_Color_24_Premium_CRT.html">spec
sheet</a>, so I have been unable to find what this flashing LED means.

I do not believe that there should be anything physically broken in the
monitor, as (to my knowledge) it hasn't been moved since I used it last
week, but I can't be sure.

Did my monitor just meet it's inevitable end and wear out? Can anyone
help? Is all hope lost?

Try unplugging it for ten minutes, then try again.

If it still doesn't work try it on a different computer and see what
happens.

Do you hear it crackle when it powers up, will static cling make paper
stick to the screen, if not did it used to?


-Landon

The monitor crackles normally, but it doesn't seem to make any static.
It sounds like it tries to turn on, but a breaker/relay clicks at the
last minute.

do the bulb test and post results. have you measured any of the power
supply lines? you'll have to give us a few more indications if you
expect useful suggestions

 

[Flyguy]

Homer J Simpson wrote:

mwpmorris@gmail.com&gt; wrote in message
news:1162839588.995972.108850@h48g2000cwc.googlegroups.com...


Could I have been exposed to anything when the glass shattered inside
the set or when I powered the thing on with the glass shattered?


No.

Do they still use mercury to flash the getter in the CRT gun assembly?
I'd be a little worried about that possbility.

 

[Michael A. Terrell]

meow2222@care2.com wrote:

Michael A. Terrell wrote:
"J. Todd" wrote:

Since warmer=drier, I might look for paper tubular
caps. When moist, they leak badly.

Paper capacitors? Transistor radios use electrolytic and mylar film
instead of paper, but the electrolytics were poor quality, and they
don't age very well. The capacitors in tuned circuits are either mica,
ceramic or polystyrene.

Lytic caps are easily tested by piggybacking. Just clip a similar value
cap on, no need for any soldering or cutting. But really its farily
pointless unless you do some fault finding first.

NT

Unless they are leaky, then "Piggybacking" is a waste of time. I
have an ESR meter, and a digital capacitor meter. On the other hand, I
would probably just replace all the old electrolytics first, then look
for other problems. It usually only takes a couple dollars worth of new
caps, and they should be replaced if you plan to actually use the radio.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

 

Flashing yellow is usually standby mode.
as if there were no signal present.
I have a GDM-FW900, Though anfter looking at yours i think its a different animal.
Im selling mine, its up on ebay right now.
item # 130046899689
I had a few bad caps in the shutdown circuit

 

[quietguy]

How many gangs on the tuning cap? Many of the 8 transistor radios had an
RF stage - if there are 3 gangs on the tuning cap that is a giveaway

David

wrongaddress@att.net wrote:

I have an old 8 gernamium transistor, protable AM radio that is noisy
on weak stations when cold. It works reasonably well when set it in the
sunshine and warms up. The problem seems to be the RF section since the
noise goes away when the volume is turned down. I'm suspecting the
germanium transistors may be the problem and wondering which one might
be replaced with a silicon variety to cure the temperature problems?

I'm not sure what all 8 transistors do. Two are in the output stage,
and another is used as a audio driver that drives the audio input
transformer.There are four RF coils, the usual oscillator (red) and
mixer (yellow) and white (1st IF) and (black (second IF). But that only
requires 6 transistors, and there are eight total. The detector is a
diode, so they didn't use a transistor for that. I haven't figured out
what the other 2 transistors do.

I'm thinking of replacing the oscillator transistor with a high gain
silicon variety to try and eliminate the temperature problems?

Any other ideas?

-Bill

 

Ancient_Hacker wrote:

wrongaddress@att.net wrote:
I have an old 8 gernamium transistor, protable AM radio that is noisy
on weak stations when cold.

By "noisy" do you mean there is lots of background hiss, or do you mean
the sound is rough and distorted?

Yes, lots of background hiss and roar at low temperature. At 80 degrees
F, it's not too bad, but at 55 degrees it whistles and squeals and the
weak stations are lost.

It works reasonably well when set it in the
sunshine and warms up.

I'm suspecting the
germanium transistors may be the problem and wondering which one might
be replaced with a silicon variety to cure the temperature problems?

No. The radio was designed to work with germanium transistors. Every
stage you change over to silicon will need to be rebiased, retuned, and
reneutralized. Not an easy job.

I'm not sure the design is the best. They used a couple resistors to
set the bias on the output stage, and when the battery voltage falls a
volt or so, the output has some crossover distortion. I fixed that
problem with a couple diodes in place of a resistor so the bias current
stays above zero as the battery voltage falls. I can now drop the
supply voltage a couple volts with no crossover distortion.

I'd start with replacing the electrolytics. Quite likely they're at
about 20% of their original selves. Weak electrolytics can make the
radio motorboat, or sound tinny and noisy.

Yes, that could be a problem, but the AGC seems to work well, so that
capacitor must be ok.

-Bill

 

[Ken Weitzel]

wrongaddress@att.net wrote:

Ancient_Hacker wrote:
wrongaddress@att.net wrote:
I have an old 8 gernamium transistor, protable AM radio that is noisy
on weak stations when cold.
By "noisy" do you mean there is lots of background hiss, or do you mean
the sound is rough and distorted?


Yes, lots of background hiss and roar at low temperature. At 80 degrees
F, it's not too bad, but at 55 degrees it whistles and squeals and the
weak stations are lost.

It works reasonably well when set it in the
sunshine and warms up.
I'm suspecting the
germanium transistors may be the problem and wondering which one might
be replaced with a silicon variety to cure the temperature problems?
No. The radio was designed to work with germanium transistors. Every
stage you change over to silicon will need to be rebiased, retuned, and
reneutralized. Not an easy job.


I'm not sure the design is the best. They used a couple resistors to
set the bias on the output stage, and when the battery voltage falls a
volt or so, the output has some crossover distortion. I fixed that
problem with a couple diodes in place of a resistor so the bias current
stays above zero as the battery voltage falls. I can now drop the
supply voltage a couple volts with no crossover distortion.

I'd start with replacing the electrolytics. Quite likely they're at
about 20% of their original selves. Weak electrolytics can make the
radio motorboat, or sound tinny and noisy.

Yes, that could be a problem, but the AGC seems to work well, so that
capacitor must be ok.

Hi Bill...

I haven't read the whole thread, so if I'm repeating anyone
else please accept my apologies.

Why not consider operating it in a warmish room, and spraying
local components one at a time (with a few minutes break in between)
with "freeze in a can" (whatever they call it in your part of the world)
until you find the component that causes it to act up.

And just for the heck of it, my bet's on a resistor.

Take care.

Ken

 

meow2222@care2.com wrote:

wrongaddress@att.net wrote:

I have an old 8 gernamium transistor, protable AM radio that is noisy
on weak stations when cold. It works reasonably well when set it in the
sunshine and warms up. The problem seems to be the RF section since the
noise goes away when the volume is turned down. I'm suspecting the
germanium transistors may be the problem and wondering which one might
be replaced with a silicon variety to cure the temperature problems?

I'm not sure what all 8 transistors do. Two are in the output stage,
and another is used as a audio driver that drives the audio input
transformer.There are four RF coils, the usual oscillator (red) and
mixer (yellow) and white (1st IF) and (black (second IF). But that only
requires 6 transistors, and there are eight total. The detector is a
diode, so they didn't use a transistor for that. I haven't figured out
what the other 2 transistors do.

I'm thinking of replacing the oscillator transistor with a high gain
silicon variety to try and eliminate the temperature problems?

Any other ideas?

-Bill

Replacing parts at random on electronics makes not one bit of sense.
There are hundreds of components and hundreds of connections, any one
of which may be to do with it.

There are about about 50 components. This is little portable radio
about the size of 2 packs of cigarettes (5.25 by 3 by 1.25). I like it
because it's easy to carry around and sounds better than the smaller
versions.

Trying to repair a radio by replacing geraniums with silicon makes even less sense.
Germanium trs are still sold new as well as used.

If you dont know what youre doing, leave it alone.

Well, if I leave it alone, I can only use it on hot days. I'm trying to
figure out a way I can use it on hot and COLD days?

Maybe you have a suggestion to overcome the temperature problems?

-Bill

 

quietguy wrote:

How many gangs on the tuning cap? Many of the 8 transistor radios had an
RF stage - if there are 3 gangs on the tuning cap that is a giveaway

David

It's just a little pocket size radio (5 X 3 X 1.5) with 2 sections for
the tuning cap.It has the usual four RF coils and input and output
audio transformers. But that only requires 6 transistors, and there are
8 used. I suppose I can trace out the connections to try and figure out
what the extra 2 transistors do.

wrongaddress@att.net wrote:

I have an old 8 gernamium transistor, protable AM radio that is noisy
on weak stations when cold. It works reasonably well when set it in the
sunshine and warms up. The problem seems to be the RF section since the
noise goes away when the volume is turned down. I'm suspecting the
germanium transistors may be the problem and wondering which one might
be replaced with a silicon variety to cure the temperature problems?

I'm not sure what all 8 transistors do. Two are in the output stage,
and another is used as a audio driver that drives the audio input
transformer.There are four RF coils, the usual oscillator (red) and
mixer (yellow) and white (1st IF) and (black (second IF). But that only
requires 6 transistors, and there are eight total. The detector is a
diode, so they didn't use a transistor for that. I haven't figured out
what the other 2 transistors do.

I'm thinking of replacing the oscillator transistor with a high gain
silicon variety to try and eliminate the temperature problems?

Any other ideas?

-Bill