Hello all,

I have an the following TV

RCA - Model #F32665
Chasis #CTC203CX

A friend of mine owned this unit for a few years, and it reciently
went out on him. His story is that one morning he went to turn on the
TV, and when he turned on the power to the room the TV made a loud
buzzing sound. He asked me to look at it (I'm a Computer Tech, have no
idea what he was thinking) - but anyways, I dont know enough about
TV's to start tearing stuff up.

Well - he just went and baught a new one instead of looking at the
repair option and asked me if I wanted it.

I took the TV apart, trying to track down the source of the sound.

pictures are here

http://www.gpetty.com/TV/

I cant specifically tell where the sound is coming from, just hard to
tell, but the pictures are of the general area.

I probably wont get it repaired either, the nearest place is about 45
minutes, and with the quote they gave me to just come out, I could buy
a new 32" TV.

If I cant fix it......what is the proper disposal of a TV of this
sort?

Thanks for any advice.

Where do you live?
Do a Google groups search for that chassis for lots of information and tips.
Aslo read www.repairfaq.org for some other hints, especially the safety
section.

If you do not want to take it on, and are close to N.E Indiana, I will take
it. (as long as it was not dropped or set outside in the rain)

David

"Guy Petty" wrote in message
om...
Hello all,

I have an the following TV

RCA - Model #F32665
Chasis #CTC203CX

A friend of mine owned this unit for a few years, and it reciently
went out on him. His story is that one morning he went to turn on the
TV, and when he turned on the power to the room the TV made a loud
buzzing sound. He asked me to look at it (I'm a Computer Tech, have no
idea what he was thinking) - but anyways, I dont know enough about
TV's to start tearing stuff up.

Well - he just went and baught a new one instead of looking at the
repair option and asked me if I wanted it.

I took the TV apart, trying to track down the source of the sound.

pictures are here

http://www.gpetty.com/TV/

I cant specifically tell where the sound is coming from, just hard to
tell, but the pictures are of the general area.

I probably wont get it repaired either, the nearest place is about 45
minutes, and with the quote they gave me to just come out, I could buy
a new 32" TV.

If I cant fix it......what is the proper disposal of a TV of this
sort?

Thanks for any advice.

Guy Petty wrote:

Hello all,

I have an the following TV

RCA - Model #F32665
Chasis #CTC203CX

A friend of mine owned this unit for a few years, and it reciently
went out on him. His story is that one morning he went to turn on the
TV, and when he turned on the power to the room the TV made a loud
buzzing sound. He asked me to look at it (I'm a Computer Tech, have no
idea what he was thinking) - but anyways, I dont know enough about
TV's to start tearing stuff up.

Well - he just went and baught a new one instead of looking at the
repair option and asked me if I wanted it.

I took the TV apart, trying to track down the source of the sound.

pictures are here

http://www.gpetty.com/TV/

I cant specifically tell where the sound is coming from, just hard to
tell, but the pictures are of the general area.

I probably wont get it repaired either, the nearest place is about 45
minutes, and with the quote they gave me to just come out, I could buy
a new 32" TV.

If I cant fix it......what is the proper disposal of a TV of this
sort?

Thanks for any advice.

Described as buzzing - perhaps the vertical output
transformer (or whatever the younger fellows call it
nowadays

Or, how about the degaussing coil?

Just thinking out loud...

Ken

On Sat, 01 May 2004 02:56:39 GMT, Ken Weitzel
wrote:



Guy Petty wrote:

Hello all,

I have an the following TV

RCA - Model #F32665
Chasis #CTC203CX

A friend of mine owned this unit for a few years, and it reciently
went out on him. His story is that one morning he went to turn on the
TV, and when he turned on the power to the room the TV made a loud
buzzing sound. He asked me to look at it (I'm a Computer Tech, have no
idea what he was thinking) - but anyways, I dont know enough about
TV's to start tearing stuff up.

Well - he just went and baught a new one instead of looking at the
repair option and asked me if I wanted it.

I took the TV apart, trying to track down the source of the sound.

pictures are here

http://www.gpetty.com/TV/

I cant specifically tell where the sound is coming from, just hard to
tell, but the pictures are of the general area.

I probably wont get it repaired either, the nearest place is about 45
minutes, and with the quote they gave me to just come out, I could buy
a new 32" TV.

If I cant fix it......what is the proper disposal of a TV of this
sort?

Thanks for any advice.

Described as buzzing - perhaps the vertical output
transformer (or whatever the younger fellows call it
nowadays

Or, how about the degaussing coil?

32" is worth fixing! It is not that old YET, CTC203 was only around
since late 1999.

Errr.... The deguassing circuit cycles once at each turn on for that
chassis.

Contstant "buzzzzzzzz!" is the power supply noise becasue of short
circuit. Not healthy and will blow out three more transistors & a
small resistor. Maybe a fuse depending how power supply main
transistor blows. If left plugged in too long.

Plug that 32" tv again, chances the power supply will blow. This
buzzing noise is the power supply trying to power into a short
circuit. That short circuit is caused by shorted horizontal
transistor for the flyback transformer. Reason for this short can be
either the L14401 coil (small round bar wrapped around with length of
copper magnet wire has hot melt glue on it. Glue broke the solder
connection on one pin. Look at L14401 solder joint real carefully.
It is very tiny break. Resoldering is short term fix. Unsolder and
remove coil, remove glue, Unplug any glue clogged that hole that wire
went through for that bad solder joint. Reinstall coil and resolder.
Replace horizontal transistor, RCA part number 237470. Test fit that
replacement transistor with one middle pin formed to fit through three
holes WITH transistor flat to the heatsink with all three leads loose
in their holes. Get small bit of heatsink grease on back of
transistor and clamp it in place like you do with a CPU and heatsink.
In thin layer please. Trim excess length and solder. Reassemble set
with all wires in their original positions in their holders.


Secondly, this might be a bad flyback transformer. Look carefully for
a tiny pinhole. This usually happens mostly on 32" and 36" ctc203
models uses same fly and same fly for either two. Not often but does
happen. Cost of that fly is only about 60.

Anyway, get the set in for estimate at good RCA shop (preferably
authorized if you're not comfortable getting into it.

Btw, this glue thing is fairly common.

Cheers,

Wizard

Haven't seen a "Vertical Output Transformer" in a few decades of TV design.
Squeal from the SMPS is indicative of excessive loading, quite often caused
by a shorted Horizontal Output Device. This can be caused by failure of the
LOPT, failure of caps in the deflection circuit (rare), and poor, glue
coated connections of L14401, which has already been addressed. Have a local
shop have a go at the tele, giving you an estimate before repairing it.
LOPT, H Output, Repair of L14401 area normally will get these sets up and
running. Nominal cost should run btw $125 - $200 pending on shop charges,
etc. IMHO you can't purchase a quality 32" tele for that charge.
"Jason D." wrote in message
...
On Sat, 01 May 2004 02:56:39 GMT, Ken Weitzel
wrote:



Guy Petty wrote:

Hello all,

I have an the following TV

RCA - Model #F32665
Chasis #CTC203CX

A friend of mine owned this unit for a few years, and it reciently
went out on him. His story is that one morning he went to turn on the
TV, and when he turned on the power to the room the TV made a loud
buzzing sound. He asked me to look at it (I'm a Computer Tech, have no
idea what he was thinking) - but anyways, I dont know enough about
TV's to start tearing stuff up.

Well - he just went and baught a new one instead of looking at the
repair option and asked me if I wanted it.

I took the TV apart, trying to track down the source of the sound.

pictures are here

http://www.gpetty.com/TV/

I cant specifically tell where the sound is coming from, just hard to
tell, but the pictures are of the general area.

I probably wont get it repaired either, the nearest place is about 45
minutes, and with the quote they gave me to just come out, I could buy
a new 32" TV.

If I cant fix it......what is the proper disposal of a TV of this
sort?

Thanks for any advice.

Described as buzzing - perhaps the vertical output
transformer (or whatever the younger fellows call it
nowadays

Or, how about the degaussing coil?

32" is worth fixing! It is not that old YET, CTC203 was only around
since late 1999.

Errr.... The deguassing circuit cycles once at each turn on for that
chassis.

Contstant "buzzzzzzzz!" is the power supply noise becasue of short
circuit. Not healthy and will blow out three more transistors & a
small resistor. Maybe a fuse depending how power supply main
transistor blows. If left plugged in too long.

Plug that 32" tv again, chances the power supply will blow. This
buzzing noise is the power supply trying to power into a short
circuit. That short circuit is caused by shorted horizontal
transistor for the flyback transformer. Reason for this short can be
either the L14401 coil (small round bar wrapped around with length of
copper magnet wire has hot melt glue on it. Glue broke the solder
connection on one pin. Look at L14401 solder joint real carefully.
It is very tiny break. Resoldering is short term fix. Unsolder and
remove coil, remove glue, Unplug any glue clogged that hole that wire
went through for that bad solder joint. Reinstall coil and resolder.
Replace horizontal transistor, RCA part number 237470. Test fit that
replacement transistor with one middle pin formed to fit through three
holes WITH transistor flat to the heatsink with all three leads loose
in their holes. Get small bit of heatsink grease on back of
transistor and clamp it in place like you do with a CPU and heatsink.
In thin layer please. Trim excess length and solder. Reassemble set
with all wires in their original positions in their holders.


Secondly, this might be a bad flyback transformer. Look carefully for
a tiny pinhole. This usually happens mostly on 32" and 36" ctc203
models uses same fly and same fly for either two. Not often but does
happen. Cost of that fly is only about 60.

Anyway, get the set in for estimate at good RCA shop (preferably
authorized if you're not comfortable getting into it.

Btw, this glue thing is fairly common.

Cheers,

Wizard

Thanks for all the info - it's more of a project now, a few of my
friends and I are tinkering with it a bit, following all the safety
precautions.

It's hard to narrow down the sound, and I'm not familiar with all the
"exact" terms for each item on the circuit boards.

The noise is similar to an alarm clock buzzing, although not as loud.
We plugged it in a few minutes and it just remained buzzing. (I know,
not the best thing, but the original owner left it on a few hours
running like that, figured it couldn't get much worse).

http://www.gpetty.com/TV2/

I put an edited picture on there, to give a general idea of where the
sound is coming from. And other small notes.

We are going to be bringing home testing equipment from the labs at
work to fool around a bit more, but before we started tearing it apart
to test and such, I figured we'd ask.

I'm going to be reading the webpages on this chasis, and I appreciate
the input.

Guy

On Sat, 01 May 2004 13:48:53 -0400, Guy wrote:

Thanks for all the info - it's more of a project now, a few of my
friends and I are tinkering with it a bit, following all the safety
precautions.

It's hard to narrow down the sound, and I'm not familiar with all the
"exact" terms for each item on the circuit boards.


Hi Guy,

To localize noise techs uses either steroscope or a listen through a
Mcdonald's drinking straw at item in turn. Extremely effective. (I
keep few of them in toolbox and invite one of my tech or boss to help
me find it. I'm deaf and can't hear small noises.

But on CTC203, I rather not blow it up more, order the RCA part number
237470 first. Check the Q14401, it WILL be shorted. Hence the buzz
noise. transistor is marked clearly on the circuit board and this
horizontal output transistor is clamped down with wide spring steel
clamp. If you have a plastic goes from square metal box running
across horizontal transistor to the power supply's heatsink. Take it
out and toss it. This plastic strap chokes the air flow for that
horizontal heatsink which is Bad Thing but good thing yours did not
have it.

Reason you hear buzz or squeal is the all SMPSes either or both
increases the "on" time and or decreases frequency to pump "Scotty,
more power!" This reasoanaces changes and made audible from parts
vibrating. More power to loads if power demands incrases to keep
voltage as stable as possible, some SMPS simply blows that instant
like in Sony. Shorted horizontal transistor is easily found with a
ohm meter (DMM).

Heating up is also consistant with bad parts that is shorted but this
is very misleading because the good parts does heat up more trying to
pump more power to something else. Also this is how some cases lets
out magic "smoke" that stink that goes with it.

Heating up pointing to the small board is the pincushion circuit to
correct pincushioning error on some CRTs. Not all models has this
active pincushion. Very nice set indeed.

Below that pincushion board, right at the mainboard you will see a
small coil which is L14401 right next to base of heatsink of
horizontal transistor where that small board is mounted to that said
heatsink. On other side of that heatsink is the Q14401 horizontal
transistor with wide steel spring clamp which you will find shorted.

Fix the L14401's glue and replace Q14401 (part number 237470) will get
that tv fixed.

That Q14401 grounds B+ through flyback tranform to put energy into the
magnetic field of the ferrite core in linear fashion and horizontal
yoke winding. B+ is 140V typically measured from cold side ground, the
SMPS transformer is the isolation but it is still hot chassis since
the SMPS circut is still hot direct to line power). Grounding B+ via
flyback transformer during beam motion just before vertical centre of
crt's face and that transistor turns off at end of scan and capacitors
and diodes, windings in both coils and flyback oscillate from back EMF
in orderly way to kick beam from left to right and fall back to the
centre at correct speed, process repeats.

This horizontal circuit exacts very heavy demand on that transistor
and have to be designed carefully during design stage of a TV.
Normally could radiate about 40W during worst cases during horizontal
transistor's turn on and turn off part of pulses, hence the heatsink
for it. Anything wrong in that horizontal circuit that transistor
goes instantly with a snap of fingers. Just one bad pulse or bad part
anywhere in the horizontal circuit is enough. One of those killer
parts like glue that cracked L14401's solder joint will do that. That
L14401 coil is the part between horizontal transformer driver (T14301)
and the horizontal transistor's base pin.

Injecting small amount of current into base pin on BJT transistors
controls amount of current going C (collector) to E (emitter) in turn
vary the voltages, this is how audio amp does or as a voltage
regulator, etc. Also can be controlled fully on for full on or fully
held low for off such as for computer, horizontal transistor for
horizontal circuit applications.

Reason TVs needs horizontal transformer driver is impendance matching
and to turn low current into high current drive with very tiny volts
and ablity to pull base negative for tiny time as required to force
horiozntal transistor off while in satrated mode. Malformed waveforms
on base drive or bad parts anywhere in horizontal circuit upsets the
tuning in turn changes waveforms, this blows that transistor because
transistor isn't turned on or off properly or way too slow or too
fast.

Also that is reason this particular transistor is required for
reliable operation, poor horizontal transistor substutition won't work
and also there is so many fake transistors out there, hence reason for
ordering that one from RCA.

I've been burned by fake parts in past. Wastes time and makes
customers unhappy with repeats (aka call backs). Choosing good
supplier is important for us and knowing which supplier does and what
doesn't is good to know.

Cheers,

Wizard

Right On, Jason: Have a person that endures bi-lateral Tinnitus with
accompanying Hypertussis try to diagnose a ringing deflection circuit. Any
listening devices that can be safely applied are an asset. I personally use
a piece of plastic rod.
"Jason D." wrote in message
...
On Sat, 01 May 2004 13:48:53 -0400, Guy wrote:

Thanks for all the info - it's more of a project now, a few of my
friends and I are tinkering with it a bit, following all the safety
precautions.

It's hard to narrow down the sound, and I'm not familiar with all the
"exact" terms for each item on the circuit boards.


Hi Guy,

To localize noise techs uses either steroscope or a listen through a
Mcdonald's drinking straw at item in turn. Extremely effective. (I
keep few of them in toolbox and invite one of my tech or boss to help
me find it. I'm deaf and can't hear small noises.

But on CTC203, I rather not blow it up more, order the RCA part number
237470 first. Check the Q14401, it WILL be shorted. Hence the buzz
noise. transistor is marked clearly on the circuit board and this
horizontal output transistor is clamped down with wide spring steel
clamp. If you have a plastic goes from square metal box running
across horizontal transistor to the power supply's heatsink. Take it
out and toss it. This plastic strap chokes the air flow for that
horizontal heatsink which is Bad Thing but good thing yours did not
have it.

Reason you hear buzz or squeal is the all SMPSes either or both
increases the "on" time and or decreases frequency to pump "Scotty,
more power!" This reasoanaces changes and made audible from parts
vibrating. More power to loads if power demands incrases to keep
voltage as stable as possible, some SMPS simply blows that instant
like in Sony. Shorted horizontal transistor is easily found with a
ohm meter (DMM).

Heating up is also consistant with bad parts that is shorted but this
is very misleading because the good parts does heat up more trying to
pump more power to something else. Also this is how some cases lets
out magic "smoke" that stink that goes with it.

Heating up pointing to the small board is the pincushion circuit to
correct pincushioning error on some CRTs. Not all models has this
active pincushion. Very nice set indeed.

Below that pincushion board, right at the mainboard you will see a
small coil which is L14401 right next to base of heatsink of
horizontal transistor where that small board is mounted to that said
heatsink. On other side of that heatsink is the Q14401 horizontal
transistor with wide steel spring clamp which you will find shorted.

Fix the L14401's glue and replace Q14401 (part number 237470) will get
that tv fixed.

That Q14401 grounds B+ through flyback tranform to put energy into the
magnetic field of the ferrite core in linear fashion and horizontal
yoke winding. B+ is 140V typically measured from cold side ground, the
SMPS transformer is the isolation but it is still hot chassis since
the SMPS circut is still hot direct to line power). Grounding B+ via
flyback transformer during beam motion just before vertical centre of
crt's face and that transistor turns off at end of scan and capacitors
and diodes, windings in both coils and flyback oscillate from back EMF
in orderly way to kick beam from left to right and fall back to the
centre at correct speed, process repeats.

This horizontal circuit exacts very heavy demand on that transistor
and have to be designed carefully during design stage of a TV.
Normally could radiate about 40W during worst cases during horizontal
transistor's turn on and turn off part of pulses, hence the heatsink
for it. Anything wrong in that horizontal circuit that transistor
goes instantly with a snap of fingers. Just one bad pulse or bad part
anywhere in the horizontal circuit is enough. One of those killer
parts like glue that cracked L14401's solder joint will do that. That
L14401 coil is the part between horizontal transformer driver (T14301)
and the horizontal transistor's base pin.

Injecting small amount of current into base pin on BJT transistors
controls amount of current going C (collector) to E (emitter) in turn
vary the voltages, this is how audio amp does or as a voltage
regulator, etc. Also can be controlled fully on for full on or fully
held low for off such as for computer, horizontal transistor for
horizontal circuit applications.

Reason TVs needs horizontal transformer driver is impendance matching
and to turn low current into high current drive with very tiny volts
and ablity to pull base negative for tiny time as required to force
horiozntal transistor off while in satrated mode. Malformed waveforms
on base drive or bad parts anywhere in horizontal circuit upsets the
tuning in turn changes waveforms, this blows that transistor because
transistor isn't turned on or off properly or way too slow or too
fast.

Also that is reason this particular transistor is required for
reliable operation, poor horizontal transistor substutition won't work
and also there is so many fake transistors out there, hence reason for
ordering that one from RCA.

I've been burned by fake parts in past. Wastes time and makes
customers unhappy with repeats (aka call backs). Choosing good
supplier is important for us and knowing which supplier does and what
doesn't is good to know.

Cheers,

Wizard

Wow, followed the directions and we got it working!

Was right on with the problem!

My hats off to the TV techs out there..

Guy

Thanks Guy, many times info is presented but not followed. The whole group
acknowledges your pleasent response.
"Guy" wrote in message
...
Wow, followed the directions and we got it working!

Was right on with the problem!

My hats off to the TV techs out there..

Guy

On Mon, 3 May 2004 18:25:33 -0400, "Art" wrote:

Thanks Guy, many times info is presented but not followed. The whole group
acknowledges your pleasent response.
"Guy" wrote in message
.. .
Wow, followed the directions and we got it working!

Was right on with the problem!

My hats off to the TV techs out there..

Guy



Bravo!!! Guy! Adjust the focus, by the way, on those RCA from factory
is bit off-focus. Very nice set and will last long time if you get
that glue out of that tiny teensy hole.

And Art's is in agreement with mine.

Cheers,

Wizard