RCA CTC 203 sound
 

Hi!
I am still trying to figure out why the sound gos out on these 203 chassis,
you pick the set up, take it to the shop plug it in to check it out and the
sound is ok, I've had a lot of these do the same thing, it has gotten to
where I just tell them to unplug the set and plug it back in again and 9
times out ao 10 the set is ok, so you are giving away info for nothing.
Need some idea about these.
Thanks
Vince

RCA CTC 203 sound
 

Vince wrote:

Hi!
I am still trying to figure out why the sound gos out on these 203 chassis,
you pick the set up, take it to the shop plug it in to check it out and the
sound is ok, I've had a lot of these do the same thing, it has gotten to
where I just tell them to unplug the set and plug it back in again and 9
times out ao 10 the set is ok, so you are giving away info for nothing.
Need some idea about these.
Thanks
Vince


Many threads about this recently. There is no real fix, but a
workarouns is a cap from a pin of the micro to somewhere else, maybe
round. Look it up.
The cap will also disable CC, so it's not a completely perfect fix.

RCA CTC 203 sound
 

Again, Thomson mentions "They are working on it" since the early CTC19X
Series. Still no fix from them other than unplugging the set and plugging it
back in. Great Design!! As mentioned, check the other threads. Putting the
cap into the set fixes the sound dropout but disables the Closed Caption.
Not a manufacturer recommend fix!
"Jumpster Jiver" wrote in message
news:kefEf.5910$J81.4135@trndny01...
Vince wrote:

Hi!
I am still trying to figure out why the sound gos out on these 203
chassis, you pick the set up, take it to the shop plug it in to check it
out and the sound is ok, I've had a lot of these do the same thing, it
has gotten to where I just tell them to unplug the set and plug it back
in again and 9 times out ao 10 the set is ok, so you are giving away info
for nothing. Need some idea about these.
Thanks
Vince
Many threads about this recently. There is no real fix, but a workarouns
is a cap from a pin of the micro to somewhere else, maybe round. Look it
up.
The cap will also disable CC, so it's not a completely perfect fix.

RCA CTC 203 sound
 

If you don't have the same source, and tune to the same channels, you may
not be able to duplicate the problem. Even if you do you may not get the
same signal condition that triggers the problem.

Do some searching. There is much discussion on this matter and patches.
You might get on some of the many tech forums where techs share advice and
fixes. You can find lots of this info in the archives of this group with a
Google search. There is also an article in "The Speaker", a newsletter
published online by NESDA Ohio and can be accessed by simply signing up at
their site. There are many useful articles there.

Some places that you might look to for resources for service techs are
below. There are many more.

http://www.repairfaq.org/
http://www.nesda-ohio.com/
www.tech-assist.org
http://wa6ati.com/
http://wa6ati.com/
http://www.anatekcorp.com/
http://come.to/teklinks


"Vince" wrote in message
...
Hi!
I am still trying to figure out why the sound gos out on these 203
chassis, you pick the set up, take it to the shop plug it in to check it
out and the sound is ok, I've had a lot of these do the same thing, it has
gotten to where I just tell them to unplug the set and plug it back in
again and 9 times out ao 10 the set is ok, so you are giving away info for
nothing. Need some idea about these.
Thanks
Vince

RCA CTC 203 sound
 

Hi. For what it is worth, something I have learned about this problem, as I
have one to play with. I have found a workaround that works like a champ,
provided you have the A/V jacks on back and either a vcr, digital cable or
sat box. Take the output from your box of choice and connect to A/V jacks.
Then switch to A/V input with remote. The sound problem doesn't seem to
affect these jacks, and you get a sharper picture to boot.

I tried disconnecting the GEM module, which seemed to do the trick, but in
reality it didn't, as I had unplugged set to try the idea out.

I will see how the A/V bypass does, but no complaint so far. I know it isn't
a fix, but it was the only option available to me, see below.

I know it is some signal sent from the broadcaster, with 2 too many bits, or
some such, that overloads a buffer. I had considered doing the cap bypass
but couldn't, as the owner is 85 years old, has 2 hearing aids, and
deinitely uses closed caption.

Danny

RCA CTC 203 sound
 

RCA CTC195, CTC197, CTC203 Audio-Dropout "Glitch"

THOMSON AUDIO DROP-OUT

There has been a situation when in some RCA/GE televisions a
low-level,
scratchy-sounding noise comes out of the speakers instead of normal
audio, or when video is muted. These problems can occur when invalid
XDS data is broadcast by television stations and received by certain
Thomson television receivers. XDS data is digital information placed
within the video signal's vertical interval of an analog (NTSC)
television transmission. This data is used by the microprocessor in
the television receiver. It may be transmitted from any analog
television channel.


Explanation of XDS data:
In each frame of video, line 21 contains a single stream of data,
containing different types of data packets. Field 1 of line 21
contains two captioning channels (CC1 and CC2) and two
"text" channels (TEXT1 and TEXT2). All four of these data
channels share that 600 cps data stream, and the information is
sorted out using packet headers. Field 2 contains a matching set of
data channels (CC3, CC4, TEXT3, and TEXT4), and can also contain
extended data services (XDS) packets.

The XDS (extended data services) provide information about the current

program, TV station, and network. Unlike the caption and text data,
they are packets rather than continuous streams of data.

XDS packets include:

Name, length, and start time of current show
Type of show, based on a set of category codes
Program content advisory (see "V-chip data" below)
Network name Station name and number Time of day National weather
service warning codes.

The "Thomson audio drop-out problem" occurs when a
broadcaster sends invalid XDS data - that is, data that does not
contain truncation packets. There are certain XDS encoders on the
market that broadcasters may use that will do this. Thomson
television receivers using 16-bit microprocessors (i.e.
CTC197/PTK195 chassis) are programmed to decode XDS data by counting
data packets. When the microprocessor encounters corrupt data with no
truncation packets, the data overflows into memory registers where it
does not belong, the first of which relate to the audio processing.
When the microprocessor
encounters this corrupt data in the audio (or even video) registers,
it
interprets it as the start of a shut-down, and mutes the audio (and/or

video).

When the unit is unplugged and replugged, it empties these registers
of the corrupt data.

It is good to know that this problem was resolved in newer chassis
designs that use 32-bit microprocessors (i.e. MM101/102 and
DTV306/307).

But the vulnerable Thomson televisions will do this as they are
receiving
invalid data from a station to which the MAIN TUNER is tuned. This is
why it is so important to find out what channel, and more
specifically, what
program the viewer was watching at the time of the anomaly.

The real solution:
Broadcasters can upgrade their equipment so that the data they send is
valid (includes the necessary truncation packets), so that their
signal is always 100% valid, and does not mess up these Thomson
receivers. Some retailers have someone assigned to contact suspected
broadcasters. Once the customer identifies the program (or
commercial) was being watched (including the time of day) when the
incident occurred, they should report it to the home
service specialist.

A final note:
XDS data may be inserted live, or played back on video tape by a
broadcaster. It can also show up on a VHS tape that the customer
recorded from a previously-aired television program.

So the fix is to place a 1mfd capacitor to ground on U13101(15). This
swamps the closed caption data to the micro and stops the reception of
the defective data packet. In the event that later on the resolve the
defective data problem the capacitor can be removed. the closed
caption feature will not work with this cap. installed.

RCA CTC 203 sound
 

Oh Boy !! Not this again....

RCA CTC 203 sound
 

What Not ?
"tvguy" wrote in message
...
Not What ?