Toshiba TV29C90 problem; Image fades to black...

[GregS]

In article <MPG.2411f8c72e7f0cb1989a37@news.individual.net>, krw <krw@att.zzzzzzzzz> wrote:

In article <49a83a82$0$2698$822641b3@news.adtechcomputers.com>,
nobody@but.us.chickens says...
On 2/27/2009 10:58 AM lesswar@gmail.com spake thus:

This is Hunter Fans Digital Thermostat Model 44360.

Lately its calibration is off by 2 to 4 degrees.

You've probably already looked for this, but are there any adjustments
(like trimmer pots) on the board?

There is often a "heat anticipator" setting that when whacked will
throw the calibration off. It's purpose is to compensate for the
thermal mass of the building and look at the rate of the
temperature rise so it doesn't overshoot. Some are better than
others.

On good thermostats the computer program adjusts the anticipation
or really looks at PID. Some also have fuzzy logic.

A thermister uses resistance to set temp calibration and gain to
adjust linearity. If any of these variables gets thrown off, they
need to be adjusted. They would be a pot of some kind.The
thermister is probably OK.

greg

 

[GregS]

In article <gojl5n$ckv$2@usenet01.srv.cis.pitt.edu>, zekfrivo@zekfrivolous.com (GregS) wrote:

In article <MPG.2411f8c72e7f0cb1989a37@news.individual.net>, krw
krw@att.zzzzzzzzz> wrote:
In article <49a83a82$0$2698$822641b3@news.adtechcomputers.com>,
nobody@but.us.chickens says...
On 2/27/2009 10:58 AM lesswar@gmail.com spake thus:

This is Hunter Fans Digital Thermostat Model 44360.

Lately its calibration is off by 2 to 4 degrees.

You've probably already looked for this, but are there any adjustments
(like trimmer pots) on the board?

There is often a "heat anticipator" setting that when whacked will
throw the calibration off. It's purpose is to compensate for the
thermal mass of the building and look at the rate of the
temperature rise so it doesn't overshoot. Some are better than
others.



On good thermostats the computer program adjusts the anticipation
or really looks at PID. Some also have fuzzy logic.

A thermister uses resistance to set temp calibration and gain to
adjust linearity. If any of these variables gets thrown off, they
need to be adjusted. They would be a pot of some kind.The
thermister is probably OK.

What I meant about the good thermostats, they look at the temperature
swing and adjust the programming to compensate. Its an on going
process. There is no way of knowing by reading the specs i just did,
to know how it opperates, unless it says.

Air currents around the thermostat can be tricky. The best method
I have found is to measure the thermostat with an IR gun. But
you said you dropped it, and I would suspect miscalibration.

greg

 

Thanks for all the replies.

There is no anticipator. It's a digital. No pots. No adjustments.
There is a coil; a crystal; a relay; a box - not an IC- from what I
can tell.
Switches that (1) indicate gas or electric; (2) enable or disable
(fuzzy logic) temperature
swing compensation just before start of the next program. { its
purpose to raise comfort level
to meet the new setting on next program before the new program starts}
And a span range is handled by keypad entry.


Anyway it's not about whether or not the t-stat meets the set
programming cycles.

The thermostat is not reading room temperature correctly.
I have 5 thermostats nailed to the wall now.
Two old style HW round mercury with anticipators, and
three digital style.
And this one is off by the greatest degree.

At room temp. 70 it reads 72. The others read 70 -71.
At 72 , the Hunter44360 reads 75.
At 74 it reads 78. And so on.

There isn't much on the circuit board other than what I described and
a few caps. I originally thought that the thermistor sensing varying
temperatures
would produce varying resistance and somehow translate that into the
room temp display.


So if it's not the thermistor, what handles the reading of room temp?

 

[Franc Zabkar]

On Sat, 7 Mar 2009 12:21:57 -0800 (PST), lesswar@gmail.com put finger
to keyboard and composed:

Thanks for all the replies.

There is no anticipator. It's a digital. No pots. No adjustments.
There is a coil; a crystal; a relay; a box - not an IC- from what I
can tell.
Switches that (1) indicate gas or electric; (2) enable or disable
(fuzzy logic) temperature
swing compensation just before start of the next program. { its
purpose to raise comfort level
to meet the new setting on next program before the new program starts}
And a span range is handled by keypad entry.


Anyway it's not about whether or not the t-stat meets the set
programming cycles.

The thermostat is not reading room temperature correctly.
I have 5 thermostats nailed to the wall now.
Two old style HW round mercury with anticipators, and
three digital style.
And this one is off by the greatest degree.

At room temp. 70 it reads 72. The others read 70 -71.
At 72 , the Hunter44360 reads 75.
At 74 it reads 78. And so on.

There isn't much on the circuit board other than what I described and
a few caps. I originally thought that the thermistor sensing varying
temperatures
would produce varying resistance and somehow translate that into the
room temp display.


So if it's not the thermistor, what handles the reading of room temp?

The thermistor handles this. It is probably connected as part of a
potential divider driven from a regulated voltage source. Maybe there
is a factory calibration routine built into the uP inside the "box"
??? How does the thermostat read at lower temperatures? High or low?
Is there a possibility that self heating may be affecting the reading?
Does the thermostat read lower with its cover removed? Maybe you could
"calibrate" your thermostat by shunting the thermistor with a high
valued resistor, or by adding a low value in series with it. Or you
could take some resistance readings at various temperatures and look
for a matching replacement.

The following test results suggest that thermistor accuracy is not
affected significantly (less than 0.5 deg C) by aging:
http://www.springerlink.com/content/tn758n7285033298/

This document ...

http://www.thermistor.com/references/Thermistor_Design_Guide.pdf

.... suggests that a replacement thermistor manufactured with the same
RT curve should require no calibration.

==============================================================
A thermistor can be defined as having an interchangeability
tolerance of ą0.1°C over the range from 0° to 70°C. This means
that all points between 0° and 70°C, are within 0.1°C of the
nominal resistance values for that particular thermistor curve.
This feature results in temperature measurements accurate to
ą0.1°C no matter how many different thermistors are substituted
in the application.
==============================================================

Here are some RT curves:
http://www.omega.com/temperature/Z/pdf/z256-257.pdf

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.

 

[Eeyore]

tommi wrote:

I've heard tantalum capacitors can get noisy or break down over time.

I suggest you get better advice. Whilst ANY cap can do that, tantalums
are better in this respect than standard electrolytic caps and I'd say
from that pic, it wouldn't be remotely likely.

Graham

 

[K7ITM]

On Feb 28, 11:35 am, tommi <billga...@microsoft.com> wrote:

On Sat  28Feb 15:08, att <n2...@att.net> wrote



"tommi" <billga...@microsoft.com> wrote:

Can you help me ID a small capacitor. The photo shows two
identical capacitors which are marked with:   225F *
Underneath that marking is a + sign followed by a long line.

http://i39.tinypic.com/2kn8u0.jpgshowing AA battery holder.

(1) Are they likely to be tantalum capacitors?

(2) Does that marking mean they are 220nF or are they 220pF?  Or
some other value?

2.2uf, voltage unknown.  They sure look like tantalums.

I've heard tantalum capacitors can get noisy or break down over time.

The device in my photo is used to power a microphone. So any noise
from it would be very unwelcome.  

Is it worth changing those capacitors to another type?  Would
something like a polyester capacitor have enough capacity for 2.2uF
and still be physically small enough to fit in the space on the
circuit board shown in my photo?

http://i39.tinypic.com/2kn8u0.jpg

--
nb:groups widened

I've used tantalums (SMT version, but built basically the same
internal construction as what shows in your picture) in an application
where I rely on them being very quiet. The caps I use are operated at
a fairly small fraction of their rated working voltage. The circuit
has been in production for years, and I've never heard of a problem.
Tantalums absolutely CAN have problems with noise, and I've run tests
that show it readily, but my experience is that they are quiet between
noise pulses and the noise pulses occur very seldom indeed if you
operate at no more than, say, 1/3 the rated voltage.

Cheers,
Tom

 

[Ben]

On Thu, 26 Feb 2009 19:29:48 +0100, RoMan Mandziejewicz wrote:

Hello mbawolski,
Wykresy widzialem wczesniej, ale jakos nie skojarzylem ze I2L to to
czego szukam
Mam wiec:
I=14[A], L=6*10E-6 [H], aktualnie rdzen RM10, AL160 ze szczelina
0.98mm
I2L = 1.2mWs, czyli dobrze patrze ze moge zejsc z rozmiarem rdzenia do
RM8 ? ( Dla AL=160 ma szczeline 0.6mm przy materiale 3F3).

Od strony nasycenia - bez problemu.

Bo to wszystko wtorne

Energia gromadzona jest w szczelinie, i RM10 ma tu spory zapas.


J.

 

[Mr Spock]

And I plonked you because you're a little dicksucker.

Stacey if you ask me nicely, you can suck my dick tooo. But if you want
me to give you some tongue, you can FUCK OFF. Your so full of vile crap,
the crabs moved out.

 

Yeah, it's a shame.I want me a rich old widow woman too, can't find me
one.
cuhulin

 

[Arfa Daily]

"David Nebenzahl" <nobody@but.us.chickens> wrote in message
news:49d80827$0$29748$822641b3@news.adtechcomputers.com...

On 4/4/2009 4:40 PM woodpecker spake thus:

We bought a fluorescent light fixture at Home Depot for our kitchen
about a year ago. It uses 3 48" T8 bulbs. It stopped working (all
bulbs) a few days ago. I had one extra new bulb, so I tried replacing
each of the bulbs. That didn't work, so I replaced all of them. Still
not working. The only other symptom was that before it went out
completely, for a few days it occasionally quickly flashed off then
back on.

Any ideas as to what my next step should be?

Yes; replacing the ballast.

(Unless someone here knows some way of testing the ballast.)

But first, just make sure that power is actually reaching the fixture, and
that there are no intermittent connections internal to the fixture. *Then*
suspect the ballast ...

Arfa

 

[Samuel M. Goldwasser]

"Arfa Daily" <arfa.daily@ntlworld.com> writes:

"David Nebenzahl" <nobody@but.us.chickens> wrote in message
news:49d80827$0$29748$822641b3@news.adtechcomputers.com...
On 4/4/2009 4:40 PM woodpecker spake thus:

We bought a fluorescent light fixture at Home Depot for our kitchen
about a year ago. It uses 3 48" T8 bulbs. It stopped working (all
bulbs) a few days ago. I had one extra new bulb, so I tried replacing
each of the bulbs. That didn't work, so I replaced all of them. Still
not working. The only other symptom was that before it went out
completely, for a few days it occasionally quickly flashed off then
back on.

Any ideas as to what my next step should be?

Yes; replacing the ballast.

(Unless someone here knows some way of testing the ballast.)



But first, just make sure that power is actually reaching the fixture, and
that there are no intermittent connections internal to the fixture. *Then*
suspect the ballast ...

And, if it's an electronic ballast that isn't potted, could be bad
solder joints on its PCB, though at this point with it being totally
dead, something may have blown.

--
sam | Sci.Electronics.Repair FAQ: 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 Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

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

 

[Franc Zabkar]

On Sun, 05 Apr 2009 08:23:55 +1000, Franc Zabkar
<fzabkar@iinternode.on.net> put finger to keyboard and composed:

FWIW, a Google search for LTF00CPXB048 then finds a Funai 6719DG
(Sylvania) 19" colour TV/VCR/DVD.

I suggest that the OP saves the "View as HTML" version of the service
manual (the PDF link is dead) before it expires from Google's cache.

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.

 

[Franc Zabkar]

On Sat, 04 Apr 2009 16:17:58 GMT, bpetria@verizon.net (Brad) put
finger to keyboard and composed:

I have an Insignia TV/VCR/DVD combo model NS-19RTR (mfg 05/06)
in my repair shop that won't turn on. Note: I do not have a SM.

The Best Buy parts site suggested that other models using the same FBT
as the Insignia NS-19RTR are the Funai 6720FDG and the Funai
MWC20T6/TV.

Service Manuals:
http://www.funai-corp.com/6pdf/sm/6719DG.pdf
http://www.funai-corp.com/6pdf/sm/6720FDG.pdf
http://www.funai-corp.com/6pdf/sm/MWC20T6.pdf

Owner's Manuals:
http://www.funai-corp.com/6pdf/om/6719DG.pdf
http://www.funai-corp.com/6pdf/om/MWC20T6.pdf
http://www.sylvaniaconsumerelectronics.com/pdf/om/6720FDG.pdf
http://www.funai-corp.com/6pdf/om/6720FDG.pdf

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.

 

[Brad]

Hi,
Here is an update:

The customer decided on buying a new set so she removed the set
from my shop and paid me the evaluation fee.

Brad

On Sat, 04 Apr 2009 16:17:58 GMT, in sci.electronics.repair Brad wrote:

Hi,
I have an Insignia TV/VCR/DVD combo model NS-19RTR (mfg 05/06)
in my repair shop that won't turn on. Note: I do not have a SM. This set was
turned off during a storm but a storm related power surge damaged it.

The main fuse is good. Raw B+ is 171V (aok), the regulated B+ measured
+43V which doesn't change when pressing the Power button. I also found
a +5V source and that was ok. There was no visual sign of damage (eg. burnt
component) anywhere. I tested several parts such as diodes, etc.

Has anyone repaired this or a similar model that was damaged by a power
surge?
Thanks in advance, Brad

Before you type your password, credit card number, etc.,
be sure there is no active keystroke logger (spyware) in your PC.

 

[Stacey Chuffo]

"Lynn" <funforum@xs4all.nl> wrote in message news:gruvj6$s2t$1@aioe.org...

"Michael A. Terrell" <mike.terrell@earthlink.net> wrote in message
news:Wd2dnWhwL-p8Pn_UnZ2dnUVZ_tednZ2d@earthlink.com...

krw wrote:

DimBulb certainly is a M$ lapdog, though not housebroken.


He never will be. He enjoys humping Bill Garte's leg WAY too much.


--
And another motherboard bites the dust!

You too could be humping somebody's leg yourself, if you could afford to
pay Allison a quarter.

or Michael Terrell can donkey punch Ashleigh Cope for free.

 

[Lynn]

"Terry" <kilowatt@charter.net> wrote in message
news:bkb7v45dlstj6ob7303nvh7vifdlf700oi@4ax.com...

American's are so stupid that they reject a much easier way of doing
things.

and you waste your time thinking about what measurement system a bunch of
fat, lazy, burger eating, bible thumping, hypocritical, cowardly morons use?

 

[Han]

"Lynn" <funforum@xs4all.nl> wrote in
news:gt1s5n$iqr$1@localhost.localdomain:

"Terry" <kilowatt@charter.net> wrote in message
news:bkb7v45dlstj6ob7303nvh7vifdlf700oi@4ax.com...
American's are so stupid that they reject a much easier way of doing
things.

and you waste your time thinking about what measurement system a bunch
of fat, lazy, burger eating, bible thumping, hypocritical, cowardly
morons use?

Hou je mond dicht, of was hem/haar eerst uit met groene zeep.

--
Best regards
Han
email address is invalid

 

[Eeyore]

Han wrote:

"Lynn" <funforum@xs4all.nl> wrote
"Terry" <kilowatt@charter.net> wrote in message

American's are so stupid that they reject a much easier way of doing
things.

and you waste your time thinking about what measurement system a bunch
of fat, lazy, burger eating, bible thumping, hypocritical, cowardly
morons use?

Hou je mond dicht, of was hem/haar eerst uit met groene zeep.

Is that Dutch or Double Dutch ?

Graham

 

[Curtis Brown]

"Lynn" <funforum@xs4all.nl> wrote in message
news:gt1v65$nku$1@localhost.localdomain...

"James Sweet" <jamessweet1@trashmail.net> wrote in message
news:gsotf5$pf7$1@news.motzarella.org...
http://picasaweb.google.com/lh/photo/vZDkQ8cEjsiEV6QAyGspMQ?feat=directlink

This cute little First Alert nightlight someone gave me a while back
lasted all of 6 hours before it failed. The lamp is a small U-shaped hot
cathode fluorescent made of tubing roughly 11mm diameter. R3 was burned
beyond recognition but measured around 32K which may or may not be close
to its original value and both cathodes in the lamp are open. All
resistors are 1/4W except for R2 which appears to be a 1/2W fusible type.

D1, D2, C1, and C2 form a half wave bridge voltage doubler. R1 and R5
discharge the capacitors when the unit is unplugged. R2 serves as the
ballast, limiting current in the tube, while R3 and R4 provide current to
heat the cathodes. Running the tube from DC can't be good for it under
the best of circumstances but I would hope these typically last longer
than this one did.

now you know why someone gave it to you

why don't you shut your ass up you fucking cunt?

 

[Han]

Eeyore <rabbitsfriendsandrelations@hotmail.com> wrote in
news:49F4804F.94BB44EE@hotmail.com:

Han wrote:

"Lynn" <funforum@xs4all.nl> wrote
"Terry" <kilowatt@charter.net> wrote in message

American's are so stupid that they reject a much easier way of
doing things.

and you waste your time thinking about what measurement system a
bunch of fat, lazy, burger eating, bible thumping, hypocritical,
cowardly morons use?

Hou je mond dicht, of was hem/haar eerst uit met groene zeep.

Is that Dutch or Double Dutch ?

Graham

"Shut up (your mouth), or first wash it out with green (lye) soap"
I'm Dutch by birth, but this outcry was out of line, even though the
sentiment may be OK.

--
Best regards
Han
email address is invalid