Toshiba TV29C90 problem; Image fades to black...

[b]

On 17 jun, 09:28, Franc Zabkar <fzab...@iinternode.on.net> wrote:

On Mon, 15 Jun 2009 16:06:10 -0700 (PDT), b
reverend_rog...@yahoo.com> put finger to keyboard and composed:

I am trying to repair a digital terrestrial set top box which had
bulging caps, would shut down and had no audio. changed the caps, box
works but still no sound. I discovered two small 3 legged smd
transistors (at least I assujme thats what they are) burned,
presumably due to high voltage and/or poor regulation from the faulty
psu.
The only reference visible on the components is a '2'. In the same
pcb there are others marked '2A', so i'm assuming these two might be
the same.

They are on the pcb as Q5 and Q6, and the pcbitself is maerked: HY650
39150 DST VER 1.7 (2004) and it has the Zoran supraTv chip

http://www.elektronikjk.republika.pl/s1.html

2A = 2N3906 / FMMT3906 / MMBT3906 / MMBT3906L / PMBT3906 / SMBT3906 /
YTS3906/ MMBT3906W / PXT3906 / SXT3906

I'd check the other 2x numbers in the above reference.

FWIW, here are service manuals for three LG set-top boxes:

http://www.jordansmanuals.com/Default.aspx?Brand=LG&Product=Set-Top-B...

Maybe they will give you a general idea as to how they work.

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

Thanks franc. I discovered the two transistors were for muting.
Removal restored the sound. that and changing the caps (C365-100uF,
C143-2200uF AND ONE OTHER 330uF) and the unit seems to work ok. model
in question: Mx-onda TDT MX-STB 5290.

2 of the bad caps were 'CHANG' mentioned here:http://www.badcaps.net/
forum/showthread.php?t=388&page=5&pp=20
hope this may be of use to others.
-B

 

[Gordon Lightfoot III]

"Sylvia Else" <sylvia@not.at.this.address> wrote in message
news:0087f50d$0$27878$c3e8da3@news.astraweb.com...

How to disable a bomb that's triggered by a satellite phone.

Step 1. Pull off the antenna.

Step 2. Get a beer.

Sylvia.

Dear Sylvia.

You will be lambasted by all and sundry for this post.
Can you please tell us how many bombs you have disabled?

 

[Sylvia Else]

Gordon Lightfoot III wrote:

"Sylvia Else" <sylvia@not.at.this.address> wrote in message
news:0087f50d$0$27878$c3e8da3@news.astraweb.com...
How to disable a bomb that's triggered by a satellite phone.

Step 1. Pull off the antenna.

Step 2. Get a beer.

Sylvia.

Dear Sylvia.

You will be lambasted by all and sundry for this post.
Can you please tell us how many bombs you have disabled?

You got your last lambasting call wrong, and this one looks like going
the same way.

But keep up the good work.

Sylvia.

 

[bernardus]

root schreef:

bernardus <bvenema@orange.nl> wrote:
Can anyone help on a U61 problem? on a panasonic dvd recorder
it seems not to be the Capacitor
neither the position of the lens.

kind regards

The manual says that the unit suffered a power drop out and
is in the process of recovering. The manual adds there
is no problem with the unit, and you just have to wait
for the recovery process to complete.
thanks but this was not the issue.

I tried it but no use.

something is broken

 

[Archimedes' Lever]

On Thu, 2 Jul 2009 21:56:48 -0700 (PDT), Deodiaus <deodiaus@yahoo.com>
wrote:

BTW, I have a follow up question.
I am buying a
AO Smith DL1056 1/2 HP Direct Drive Blower Motor
motor, which needs a 10 mF capacitor (according to manufacturer's
specs),
but the AC guy put in a 7.5 mF cap.
Any reasons why he would do that other than that's what he had
available (because he had to make a special run to grainger anyway?

It will likely work, but it is almost certain he got that because it
was all that was available or because he thought it was the right animal
for the job.

 

[Deodiaus]

BTW, I have a follow up question.
I am buying a
AO Smith DL1056 1/2 HP Direct Drive Blower Motor
motor, which needs a 10 mF capacitor (according to manufacturer's
specs),
but the AC guy put in a 7.5 mF cap.
Any reasons why he would do that other than that's what he had
available (because he had to make a special run to grainger anyway?

 

[Stormin Mormon]

Can't think of any.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"Deodiaus" <deodiaus@yahoo.com> wrote in message
news:a7166cd5-854d-405a-aa98-2f08d1d78de1@b14g2000yqd.googlegroups.com...
BTW, I have a follow up question.
I am buying a
AO Smith DL1056 1/2 HP Direct Drive Blower Motor
motor, which needs a 10 mF capacitor (according to
manufacturer's
specs),
but the AC guy put in a 7.5 mF cap.
Any reasons why he would do that other than that's what he
had
available (because he had to make a special run to grainger
anyway?

 

[Tzortzakakis Dimitrios]

? "Deodiaus" <deodiaus@gmail.com> ?????? ??? ??????
news:ca72dab6-4148-4e2d-ab73-6e5faba6a000@a36g2000yqc.googlegroups.com...

The motor I had in there is
http://americanhvacparts.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=MOT2426003&Category_Code=fasco-luxa
which as you can see here also comes recommended with a 7.5 MFD cap,
but the manufacturer suggests 10 MFD.

That's a much better capacitor than the crap plastic ones we have in EU;_) I

have no idea why they recommend 10 uF, since the website has a link to a GE
7.5 uF, and the electrician put a 7.5 uF.

Gott ist tod.
(your signature in German).
(Pronounced toont).


--
Tzortzakakis Dimitris
major in electrical engineering
mechanized infantry reservist
hordad AT otenet DOT gr

 

[Deodiaus]

The motor I had in there is
http://americanhvacparts.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=MOT2426003&Category_Code=fasco-luxa
which as you can see here also comes recommended with a 7.5 MFD cap,
but the manufacturer suggests 10 MFD.

God is Dead
-Nietzsche

 

[Dave M]

"Deodiaus" <deodiaus@yahoo.com> wrote in message
news:014fa559-8565-4a9e-82ff-bd701e61d1ac@37g2000yqp.googlegroups.com...

The other issue came up when I was looking at the new motor.
The one I had was a one speed motor.
The new one is 3 speed.
Ok, which speed should I choose?
High, med, or low?
I guess a high speed will give you more circulation, but consume more
electricity.
Any estimates on how much this will affect my energy consumption?
Should I just punt and chose medium speed?
--

Look at the nameplate on the old motor. The rated speed should be there.
Choose the same (or closest) speed on the new motor and wire it up
accordingly.
Make sure the new motor is wired to turn in the same direction as the old
motor. The capacitor hookup will determine the direction of rotation.
Rotation is always specified when looking at the shaft end of the motor.
Energy consumption will be modestly different on different brand motors, but
the difference will probably be negligible if the HP rating is the same,
regardless of the speed.

Cheers
Dave M.

 

[Deodiaus]

The other issue came up when I was looking at the new motor.
The one I had was a one speed motor.
The new one is 3 speed.
Ok, which speed should I choose?
High, med, or low?
I guess a high speed will give you more circulation, but consume more
electricity.
Any estimates on how much this will affect my energy consumption?
Should I just punt and chose medium speed?
--
God is Dead
and I know German!

 

[Big Bob]

Bull Shit!

motor. The capacitor hookup will determine the direction of rotation.

If it is a reversible type motor, there will be 2 wires to change.

Rotation is always specified when looking at the shaft end of the motor.

Again Bull shit. Have you ever looked in a motor catalog and wondered what
they mean when it says CCW Lead End?

Don't make statements not true that can cost somebody aggravation or money.

Stupid Rookie

 

[PeterD]

On Fri, 3 Jul 2009 21:20:17 -0500, "Big Bob" <bob@l.net> wrote:

Bull Shit!

motor. The capacitor hookup will determine the direction of rotation.

If it is a reversible type motor, there will be 2 wires to change.

Rotation is always specified when looking at the shaft end of the motor.

Again Bull shit. Have you ever looked in a motor catalog and wondered what
they mean when it says CCW Lead End?

Care to post a reference to a catalog page that says that?

 

[Dave M]

"PeterD" <peter2@hipson.net> wrote in message
news:soou45140joa8fu854tp3tph5e1o0ua1tl@4ax.com...

On Fri, 3 Jul 2009 21:20:17 -0500, "Big Bob" <bob@l.net> wrote:

Bull Shit!

motor. The capacitor hookup will determine the direction of rotation.

If it is a reversible type motor, there will be 2 wires to change.

Rotation is always specified when looking at the shaft end of the motor.

Again Bull shit. Have you ever looked in a motor catalog and wondered
what
they mean when it says CCW Lead End?


Care to post a reference to a catalog page that says that?

My, what venom!!! Cool down and let's converse without the profanity.

You're right ... when I spoke of the rotation, I knew what I wanted to
write, but I left out the pertinent word, which was "opposite". I meant to
say that the direction of rotation is almost always specified by looking at
the end opposite the shaft. My apologies to the OP for the error.
I don't have any books or catalogs on AC motor design and construction; I
was taught many years ago by an A/C professional installer and service guy
that the connection of the capacitor in the motor's circuit changes
direction of the motor, usually by changing the connection of the
capacitor's wires on the terminal board. Perhaps motor construction
techniques have changed over the years?

Dave M

 

[PeterD]

On Sat, 4 Jul 2009 11:56:49 -0400, "Dave M" <masondg4499@comcast.net>
wrote:

"PeterD" <peter2@hipson.net> wrote in message
news:soou45140joa8fu854tp3tph5e1o0ua1tl@4ax.com...
On Fri, 3 Jul 2009 21:20:17 -0500, "Big Bob" <bob@l.net> wrote:

Bull Shit!

motor. The capacitor hookup will determine the direction of rotation.

If it is a reversible type motor, there will be 2 wires to change.

Rotation is always specified when looking at the shaft end of the motor.

Again Bull shit. Have you ever looked in a motor catalog and wondered
what
they mean when it says CCW Lead End?


Care to post a reference to a catalog page that says that?

My, what venom!!! Cool down and let's converse without the profanity.

Venom? I asked for a catalog reference page.

Profanity? None of the words I wrote could ever be considered
profanity.

Maybe you should learn some more of the English, such as the
definition of venom, profanity, and heck every word that I wrote.

 

[TheQuickBrownFox]

On Sat, 4 Jul 2009 21:13:41 -0700 (PDT), Deodiaus <deodiaus@yahoo.com>
wrote:

tolerance might
be off enough to throw the engine off.

They are called motors. Your credibility has taken a dive.

 

[Deodiaus]

Talking to a friend who is an electrician, he told me that maybe just
the capacitor might be of the wrong capacitance.
The problem with buying one off the shelf is that its tolerance might
be off enough to throw the engine off.
Does anyone know how to calculate the torque for an engine with a
capacitance?
I use to know this 30 years ago, but now, don't even know how to
google this question properly!!
Using a 7.5 MFD cap did not work. I tried a 10 MFD cap, which worked
for 10 mins.
BTW, I found a cheap motor at
https://www.plumbersstock.com/product.html?partNumber=12476
Does anyone have experience with this brand,
PARTNERS CHOICE ??

 

[Wild_Bill]

It sounds as though you are in over your head, and it's time to get a
qualified, experienced person to take over the job.

A residential air system blower motor should work about the same with a
properly rated AC capacitor of 7.5uF or 10uF value (for a motor that's
marked for either a 7.5uF or a 10uF), with only a small difference in motor
speed.
These motors are typically PSC permanent split capacitor type motors, and
may be reversible, but may be designed to operate more efficiently/cooler in
one direction.

The motor you referred to is not a cheap motor, it's just not an exessively
inflated priced motor.
New surplus blower motors can be found at numerous surplus dealers for about
$30 or less, plus shipping.

--
Cheers,
WB
..............


"Deodiaus" <deodiaus@yahoo.com> wrote in message
news:f47b22c7-bfd1-438c-8785-99f43b593192@n11g2000yqb.googlegroups.com...

Talking to a friend who is an electrician, he told me that maybe just
the capacitor might be of the wrong capacitance.
The problem with buying one off the shelf is that its tolerance might
be off enough to throw the engine off.
Does anyone know how to calculate the torque for an engine with a
capacitance?
I use to know this 30 years ago, but now, don't even know how to
google this question properly!!
Using a 7.5 MFD cap did not work. I tried a 10 MFD cap, which worked
for 10 mins.
BTW, I found a cheap motor at
https://www.plumbersstock.com/product.html?partNumber=12476
Does anyone have experience with this brand,
PARTNERS CHOICE ??

 

[Wild_Bill]

The capacitor in this discussion is a Run capacitor, not a start capacitor.
Your progression to this point has been backwards.

When the motor hums instead of starting, it's not because the value needs to
be 8.645789uF, it's because the motor is not wired properly.

You need a qualified, experienced person to take care of the installation.

--
Cheers,
WB
..............


"Deodiaus" <deodiaus@yahoo.com> wrote in message
news:b6e02d73-4a51-42b1-b1e1-a1c41f34b993@d4g2000yqa.googlegroups.com...

Actually, where do I find a site with the physics of starter windings
on motors explained. 30 years ago, I had someone explain this to me
in a class, but I have forgotten it all.
Any good descriptive web sites??

BTW, does anyone know of cheaper motors on the web?
https://www.plumbersstock.com/product.html?partNumber=12476
The above site lists some substitute motors, but some just hang my
browser .

 

[Deodiaus]

Actually, where do I find a site with the physics of starter windings
on motors explained. 30 years ago, I had someone explain this to me
in a class, but I have forgotten it all.
Any good descriptive web sites??

BTW, does anyone know of cheaper motors on the web?
https://www.plumbersstock.com/product.html?partNumber=12476
The above site lists some substitute motors, but some just hang my
browser .