RCA CTC177

[Ken Weitzel]

Hi...

Wonder if anyone can point me where I might
buy/beg/borrow/steal or download a schematic
for a RCA CTC177 chassis?

Got one here, just went dead. Power supplies
are up but won't turn on. Nothing does anything

Hints and tips also gratefully accepted

Would be great for the cottage could I but get it
going again...

Thanks in advance, and take care.

Ken

 

[Sofie]

Ken Weitzel:
Do a google archival search and you will probably come up with on board
tuner ground re-soldering.... and EPROM replacement.... among other
possibilities.
Other good information on the web site for this newsgroup at
http://www.repairfaq.org/

 

[David]

www.repairfaq.org has tons of information on that series of chassis.

Pay particular attention to the tuner ground problem and corrupted eeprom
causing dead set. You will need an extensive array of equipment (for a
hobbyist) to properly realign the tuner section of the tv set after
replacing the eeprom.

As to the service manual, you can buy one from any Thomson authorized parts
distributor, around $45.

David

 

[Jason D.]

Hi...

Wonder if anyone can point me where I might
buy/beg/borrow/steal or download a schematic
for a RCA CTC177 chassis?

Got one here, just went dead. Power supplies
are up but won't turn on. Nothing does anything

Hints and tips also gratefully accepted

Would be great for the cottage could I but get it
going again...

Thanks in advance, and take care.

Ken

This chassis requires speciality tools: RF generator that outputs
specific channels with video of your favorite, dmm to measure the AFT
voltage, also may need scope and chipper check w/ clip adapter is
asoluately required to reinitialize eeprom. Aligning tuner takes
three adjustments for one channel. There is 19 channels total to
align there's 57 adjustments to do, including stereo detection
adjustments too in section 77. The tuner adjustments are in 78 level.

The 76 is for the horizontal freq, horizontal, pincushion, vertical
size & linearity, color balance.

Redoing the solder joints must do the all: Micro shield grounds,
tuner grounds (must take the bottom tin lid off.) repair faq section
has this details.

This is why you need to send this tv to the RCA shop whom does this
daily especially for reintializing and adjustments. Usually 100 to
140 for this job.

Reintializing that eeprom only refreshes the small area for the micro
not the adjustment info areas so there's chances that doesn't need to
adjustment.

Prior to this total failure, I'm wondering why you didn't caught on
there was plenty of warning signs like intermittent snow, top vertical
drop down (not the fold over) etc that signals the grounds IS failing.
Caught early, it's easy and no adjustments usually but this time have
to bite the nail and pay someone to straighten tv out.

Cheers,

Wizard

 

[John Del]

Subject: Re: RCA CTC177

From: [email protected] (Jason D.)
Date: 2/22/04 6:10 PM Pacific Standard Time
Message-id: <[email protected]>

This is why you need to send this tv to the RCA shop whom does this
daily especially for reintializing and adjustments. Usually 100 to
140 for this job.

Is that Canadian? Here on the East Coast US, a typical carry in for this type
of failure is less than $100, with the proper updates and replacement of the
smps electrolytics.

John Del
Wolcott, CT

"I'm just trying to get into heaven, I'm not running for Jesus!"
Homer Simpson

(remove S for email reply)

 

[RayRay]

This chassis requires speciality tools: RF generator that outputs
specific channels with video of your favorite, dmm to measure the AFT
voltage, also may need scope and chipper check w/ clip adapter is
asoluately required to reinitialize eeprom. Aligning tuner takes
three adjustments for one channel. There is 19 channels total to
align there's 57 adjustments to do, including stereo detection
adjustments too in section 77. The tuner adjustments are in 78 level.

The 76 is for the horizontal freq, horizontal, pincushion, vertical
size & linearity, color balance.

Redoing the solder joints must do the all: Micro shield grounds,
tuner grounds (must take the bottom tin lid off.) repair faq section
has this details.

This is why you need to send this tv to the RCA shop whom does this
daily especially for reintializing and adjustments. Usually 100 to
140 for this job.

Reintializing that eeprom only refreshes the small area for the micro
not the adjustment info areas so there's chances that doesn't need to
adjustment.

Prior to this total failure, I'm wondering why you didn't caught on
there was plenty of warning signs like intermittent snow, top vertical
drop down (not the fold over) etc that signals the grounds IS failing.
Caught early, it's easy and no adjustments usually but this time have
to bite the nail and pay someone to straighten tv out.

Cheers,

Wizard

As far as reprogramming the EEPROM is concerned, this is what I did
and didn't need any special tools:

First, remove the old EEPROM and install a socket in it's place, then
plug the new EEPROM in. Turn on the TV, then turn it back off. Now, do
not unplug the set. Remove the new EEPROM from the socket and put the
old one back in. The set should power back up. When it does, go into
the programming mode and write down all of the values. You'll need
some codes to access all of the programming parameters. Perhaps
someone here has them. After writing down all of the values, power
down the set and install the new EEPROM again. Now power up the set
again, go into the programming mode, and enter in all of the values
previously written down. I did this to two of these sets and had
success with both, no special equipment needed. Hope this helps, Ray.

 

[Sofie]

RayRay:
The do-it-yourself method that you have used and described in your post may
or may not be fully successful in many repairs since SOME or MANY of the
parameters that you are copying from the bad EPROM chip may be
corrupted..... that is why the television is not powering up to start with.
I would certainly want the tech that performed an expensive repair
re-soldering the tuner grounds, replacing faulty parts and replaced a
corrupted EPROM in my television to check ALL the parameters with the proper
test equipment and procedures.... a TCE Chipper Checker makes the job a
little less time consuming, less mistakes, more reliable and more
complete..... not to mention less expensive because of the labor time saved.

 

[Ken Weitzel]

Thanks, David.

I didn't read more than 5 or 10 lines on that site
before they gave me the answer!

Sincerely appreciated!

Take care.

Ken

 

[Ken Weitzel]

Hi...

That site is a goldmine. They had the answer for
me before I fully comprehended the question

Thanks!

Take care.

Ken

 

[Ken Weitzel]

This chassis requires speciality tools: RF generator that outputs
specific channels with video of your favorite, dmm to measure the AFT
voltage, also may need scope and chipper check w/ clip adapter is
asoluately required to reinitialize eeprom. Aligning tuner takes
three adjustments for one channel. There is 19 channels total to
align there's 57 adjustments to do, including stereo detection
adjustments too in section 77. The tuner adjustments are in 78 level.

The 76 is for the horizontal freq, horizontal, pincushion, vertical
size & linearity, color balance.

Redoing the solder joints must do the all: Micro shield grounds,
tuner grounds (must take the bottom tin lid off.) repair faq section
has this details.

This is why you need to send this tv to the RCA shop whom does this
daily especially for reintializing and adjustments. Usually 100 to
140 for this job.

Reintializing that eeprom only refreshes the small area for the micro
not the adjustment info areas so there's chances that doesn't need to
adjustment.

Prior to this total failure, I'm wondering why you didn't caught on
there was plenty of warning signs like intermittent snow, top vertical
drop down (not the fold over) etc that signals the grounds IS failing.
Caught early, it's easy and no adjustments usually but this time have
to bite the nail and pay someone to straighten tv out.

Cheers,

Wizard

Hi Wizard...

The site the others suggested had the answer for
me instantly! One 1/4 resister open

But you ask why I didn't notice something going on,
so even though it will bore you I must answer...

That old (I think mid 90's or so) TV set stays at the
cottage. I'm an old retired guy, and love to go up
there. But NOT to watch TV; I love my kids and
grandkids to spend most or all of the summer there too.

So, I spend the days watching the grand kids run and laugh
and play and swim and fish... their joy of life make me
young and healthy again...

And after they're asleep, I spend the late evenings
enjoying the company of my daughters and sons in law,
sharing little tidbits of their life story with them...

So, you see, there is NO interest in TV at all... it's
only there for the youngsters if there's a rainy day
so they can watch cartoons or a movie.

And that's why I saw nothing happening.

Take care.

Ken

 

[James Sweet]

Thanks, David.

I didn't read more than 5 or 10 lines on that site
before they gave me the answer!

Sincerely appreciated!

Take care.

Ken

Hmm, makes me think that it might not be a bad idea to save the data off the
eeprom of the sets I own in case something goes wrong, is there much danger
in corrupting them by desoldering to pop them in the reader/burner I have?

 

[Tom Del Rosso]

In James Sweet typed:

Hmm, makes me think that it might not be a bad idea to save the data
off the eeprom of the sets I own in case something goes wrong, is
there much danger in corrupting them by desoldering to pop them in
the reader/burner I have?

But if something happened to the set, wouldn't you have to realign it
anyway?

What do you use for a signal when you align them, BTW? Does it have to
be modulated video or can it be a sine at the tuner frequency?