RCA DTV306 Hdrive problem

[JURB6006]

Hey all;

Set goes shutdown pretty quick. Found out there is no drive to the Hout,
therefore it's in lack-of-sweep shutdown. This drive is supposed to come from a
standup board incorprating a deflection chip, I dont remember the number but
it's an advanced chip with PCC output and who knows what else.

This chip appears to ONLY take a V sync signal, no horizontal coming in
according to the print. The H input of the chip is grounded according to the
schematic, and there s a seperate EPROM on that board. Can it really get all of
that info that way ? I guess so.

What I've seen,,,,,, HVOT works at a low level B4 it shutsdown. Hout never gets
any drive but does get B+. I'm pretty sure this model incorporates sweep-loss
shutdown or else the tubes could be BUBAR.

Problem is I don't understand is there appears to be no H input to this chip,
is it totally bus conteolled ?

Any help s appreciated and TIA

JURB

 

[Art]

Suggestion, if you don't have the Thompson CD and all the troubleshooting
information this will turn into a real big dog in a hurry. Check the crts
for a burn in the center, in these sets there are modifications to the grid
kick circuit that must be preformed before replacing burnt crts. The burns
were caused by loss of sweep and the failure of the grid bias circuit to cut
off the crts before the bright flash in the center occurred. Only takes once
to flash burn these sets!! The SIP board itself tends to be rather reliable
and not a source of the problem, however the support power supplies do pose
an aggravation. Also many the drive signals come form the mico in the DM1
assembly, (Satellite Receiver). E-Mail me if you want further materials that
I do have available. Art
"JURB6006" <jurb6006@aol.com> wrote in message
news:20040206015750.13001.00001842@mb-m02.aol.com...

Hey all;

Set goes shutdown pretty quick. Found out there is no drive to the Hout,
therefore it's in lack-of-sweep shutdown. This drive is supposed to come
from a
standup board incorprating a deflection chip, I dont remember the number
but
it's an advanced chip with PCC output and who knows what else.

This chip appears to ONLY take a V sync signal, no horizontal coming in
according to the print. The H input of the chip is grounded according to
the
schematic, and there s a seperate EPROM on that board. Can it really get
all of
that info that way ? I guess so.

What I've seen,,,,,, HVOT works at a low level B4 it shutsdown. Hout never
gets
any drive but does get B+. I'm pretty sure this model incorporates
sweep-loss
shutdown or else the tubes could be BUBAR.

Problem is I don't understand is there appears to be no H input to this
chip,
is it totally bus conteolled ?

Any help s appreciated and TIA

JURB

 

[Jason D.]

On Fri, 6 Feb 2004 05:57:56 -0500, "Art" <stubby@comcast.net> wrote:

Suggestion, if you don't have the Thompson CD and all the troubleshooting
information this will turn into a real big dog in a hurry. Check the crts

Snip

I second Art's recommandation for CDs and study the training part
comes on that same CD. MMCxxx, DTVxxx are most complicated chassis
and very sulky chassis to tame. Complex barely describes this and can
be a dog if one is not famillar with them. (Usually cracked traces
because of poor chassis support design because of long, heavy chassis
and standby SMPS blown to bits because of bad batch of diodes, you can
see it easily by a medium sized SMPS transformer is a crispy resistor
at a diagonal location, and usually black soot around the SMPS
transistor.) I can supply the list of this parts to 100% repair this.

Oh, be 100% sure the rear circuit board (this green double sided with
scads of inputs and ICs on it, micro & jungle, etc lives on it also.)
is repairable otherwise, it is about 1500. OUCH!!

DTVxxx/MMCxxx chassis has multiple trip circuits all strung along on
one circuit and trip one of them and you have a shutdown. Catch 22.

ATC221 is also complex but bit better.

Chipper check II w/ new adapters is required not just by choice for
these newer chassies for those two. I managed to do the convergence
without chipper check on ATC311.

Cheers,

Wizard

"JURB6006" <jurb6006@aol.com> wrote in message
news:20040206015750.13001.00001842@mb-m02.aol.com...
Hey all;

Set goes shutdown pretty quick. Found out there is no drive to the Hout,
therefore it's in lack-of-sweep shutdown. This drive is supposed to come
from a
standup board incorprating a deflection chip, I dont remember the number
but
it's an advanced chip with PCC output and who knows what else.

This chip appears to ONLY take a V sync signal, no horizontal coming in
according to the print. The H input of the chip is grounded according to
the
schematic, and there s a seperate EPROM on that board. Can it really get
all of
that info that way ? I guess so.

What I've seen,,,,,, HVOT works at a low level B4 it shutsdown. Hout never
gets
any drive but does get B+. I'm pretty sure this model incorporates
sweep-loss
shutdown or else the tubes could be BUBAR.

Problem is I don't understand is there appears to be no H input to this
chip,
is it totally bus conteolled ?

Any help s appreciated and TIA

JURB

 

[JURB6006]

Hi and thanks;

Suggestion, if you don't have the Thompson CD and all the troubleshooting
information this will turn into a real big dog in a hurry

I do have the CD. What I lack is a training manual. The only thing I can
discern is pin 14 (IIRC) as any kind of clock input, and it has a varactor
based VCO feeding it. That part of the circuit is working. The Hdrive output
pin is flat @ 8 volts. Vcc is there etc., I suspect the IC, but when I found
the whole board was like $32 I ordered it, but I find it NLA (NLA ! ? set was
built in 2000 !) Our miracle parts guy found one but they're gouging us $50 for
it. Perhaps they know something we don't ?

If you have training materials for these things you'd be willing to share with
me they would be greatly appreciated. I'll try to return the favor.

I remember the old CTC169 print had quite a bit of useful info, but I have
searched the entire DTV306 part of the disk and have found nothing comparable,
except on the power supply. Even though I am VERY not fond of the Force
software on the NAP CDs, I think I like this even less, if that's actually
possible. Friggin thing is pointed to drive N: and you can't seem to get out of
it, I figured out how to get directly to the DWG files and I think I can find
other progs to open them up.

As much as I'm not really fond of Hitachis, I think they might become the least
unrecommended new buy. This because you can just DL regular PDFs from them.
Thompsom really should do that, they're percieved as an American company, they
have a good market share, their stuff is possible to repair (despite their best
efforts it sometimes seems) and their CRTs seem to hold up.

Anyway, you can have the soapbox back for now, it's Friday and I am waiting for
the crowd. It's gonna be pizza time and they will ante up. As far as this job,
I'll let you know if the board cures it. I would still like to get my hands on
a training manual for this thing. Might just buy one if nothing else.

I'll send you a seperate email with my real email address soon. I'll use an
appropriate header so I don't get lost in spam.

Thanks again.

JURB

 

[Art]

Presume that he has a shop and does this for a living, Eh. Even the best
techs have a FUBAR once in a while that requires outside assistance. Or are
you god??
"Ken G." <goodguyy@webtv.net> wrote in message
news:26998-40243FE7-404@storefull-3252.bay.webtv.net...

Art you forgot to just tell him to take it to a shop

 

[Ken G.]

Art you forgot to just tell him to take it to a shop

 

[Jason D.]

On 07 Feb 2004 01:31:35 GMT, jurb6006@aol.com (JURB6006) wrote:

Hi and thanks;

Suggestion, if you don't have the Thompson CD and all the troubleshooting
information this will turn into a real big dog in a hurry

I do have the CD. What I lack is a training manual. The only thing I can
discern is pin 14 (IIRC) as any kind of clock input, and it has a varactor
based VCO feeding it. That part of the circuit is working. The Hdrive output
pin is flat @ 8 volts. Vcc is there etc., I suspect the IC, but when I found
the whole board was like $32 I ordered it, but I find it NLA (NLA ! ? set was
built in 2000 !) Our miracle parts guy found one but they're gouging us $50 for
it. Perhaps they know something we don't ?

If you have training materials for these things you'd be willing to share with
me they would be greatly appreciated. I'll try to return the favor.

I remember the old CTC169 print had quite a bit of useful info, but I have
searched the entire DTV306 part of the disk and have found nothing comparable,
except on the power supply. Even though I am VERY not fond of the Force
software on the NAP CDs, I think I like this even less, if that's actually
possible. Friggin thing is pointed to drive N: and you can't seem to get out of
it, I figured out how to get directly to the DWG files and I think I can find
other progs to open them up.

Thomson's CDs are fine and don't see a problem with them. NAP's
force32 stuff is AWFUL and must get new key every so often from NAP.

Your computer has auto insertion disabled or cd program not run to
install the thing so you can view the schematics. CDs from thomson is
unsecured. Get it installed and working first.

Accessing schematics in my typical repair on RCA goes like this:
insert a RCA cd for that chassis I'm working on. Computer autolaunches
program that displays listings by model, I choose one (either double
click on it or press view button) The program now presents the
default menu. I choose schematics from that menu and then deflection
processing or like that to look at jungle area as if I was working on
DTV306 like you have instead of digging through CD's contents with
exploder.

We have nearly whole range of thomson CDs all the way from CTC17x to
this latest ITCxxx (came out last year). Right now my boss is trying
to get the CD for CTC169 DTV version, already ordered long ago and
credit was charged but no cd. Do have prints for PTV only but this is
not 100% same as DTV version of 169. I get lot of 169'ers to work on
I does need the DTV version on cd. Prints is available but more
expensive.

Training stuff is available both from their website & on CD buy it for
norminal cost. I use it lot, many of these are found on the CDs so I
took use of it to be good at fixing them and understand them better.

Samsung usually & JVC (sometimes) made me chase dogs for long time
because their schematics is good but too little on info (theory of
operation). In Samsung's case I discovered undocumented programming
design in samsung set that reboots if you try to adjust that volume
level but it is "fixed" if I run reset in the service mode (reset is
partial clearing portions of micro's memory contents NOT eeprom!).
Long as that tv was left plugged; turn on and off, play with it is all
day is fine. Then tv is back to bad boy when unplugged then plugged
back in. That was when this "power loss" event data got written into
eeprom, plug tv back in eeprom is read and rest of time eeprom is left
alone and not read or written at all. That part was not typical
design. Thomson's writes & reads eeprom often.

That eeprom's has bad bit in one byte that where volume level info is
read into micro's memory during plug in. Adjusting corrupted volume
info in memory rebooted micro. New eeprom fixed that.

Enjoy your weekend.

Cheers,

Wizard

As much as I'm not really fond of Hitachis, I think they might become the least
unrecommended new buy. This because you can just DL regular PDFs from them.
Thompsom really should do that, they're percieved as an American company, they
have a good market share, their stuff is possible to repair (despite their best
efforts it sometimes seems) and their CRTs seem to hold up.

Anyway, you can have the soapbox back for now, it's Friday and I am waiting for
the crowd. It's gonna be pizza time and they will ante up. As far as this job,
I'll let you know if the board cures it. I would still like to get my hands on
a training manual for this thing. Might just buy one if nothing else.

I'll send you a seperate email with my real email address soon. I'll use an
appropriate header so I don't get lost in spam.

Thanks again.

JURB

 

[JURB6006]

Yes I have a shop and over 25 yrs experience. What I don't have is an attitude.
You've met the type, walk by and see a tech. working on something and you
recognize the symptom and try to tell him, the idiot'll snarl at you as if you
insulted his competence !

I pretty much ran this down, but as jpero said, there are some wierd designs
out there and you never know. I ask for assistance sometimes when I'm in new
territory, not because I'm unable to troubleshoot, but because I don't want to
miss anything. Those times when I'm completely lost are rare indeed.( it does
happen )

Now, someone mentioned the training part of the Thomson CD, just how do you get
to that ? I looked around and found some stuff on the power supply, but not
much else.

One of these days I'm going to make a copy of that CD and bring it home, as
much as this may dismay copyright attorneys and their ilk. Who knows what I
might find. My next little pet project might be to make Force run off the
harddrive because the CD is too damslow.

Anyway, my first DTV306, after about 5 minutes I told the boss we needed a
print. I knew I wasn't looking at a toaster, so I agree with those telling me I
need the service info. Doing without it is literally scary, even to me. I used
to be real good at reverse engineering, but this has become too difficult with
alot of newer stuff. I'm not fond of being dependant on the manufacturer, a
company with interests that are diametrically opposed to servicers, but
alternatives are lacking.

Thanks again to all who read and responded.

JURB

 

[John Del]

Subject: Re: RCA DTV306 Hdrive problem
From: jurb6006@aol.com (JURB6006)
Date: 2/7/04 10:50 AM Pacific Standard Time

One of these days I'm going to make a copy of that CD and bring it home, as
much as this may dismay copyright attorneys and their ilk. Who knows what I
might find.

In order to run the CD properly, you need to run it from the Electronic Service
program, which I believe is included on the CDs anyway. Look in the contents
for an installation program.

I might have the DTV training manual in paper. I'll check Monday to see if I
do.

John

 

[Bill Jr]

Jeff,
There is a training manual set for all the new DTV.
It covers the MMxxx, MMCxxx, DTVxxx and CTC2xx sets.
We just acquired it from Thomson for around $69
And its "paper"
Just point your browser to www.thomsonnetwork.com and click on Publications
Ordering.
Follow to "Subscription Packages and Special Offers"
What you want is TMMMMCDTV
Good Information.

Good Luck,
Bill Jr






"John Del" <ohger1s@aol.com> wrote in message
news:20040207204827.11576.00001522@mb-m12.aol.com...

Subject: Re: RCA DTV306 Hdrive problem
From: jurb6006@aol.com (JURB6006)
Date: 2/7/04 10:50 AM Pacific Standard Time

One of these days I'm going to make a copy of that CD and bring it home,
as
much as this may dismay copyright attorneys and their ilk. Who knows what
I
might find.

In order to run the CD properly, you need to run it from the Electronic
Service
program, which I believe is included on the CDs anyway. Look in the
contents
for an installation program.

I might have the DTV training manual in paper. I'll check Monday to see
if I
do.

John

 

[Art]

Jurb: I've a cd, self generated, not copyrighted, which are supplimental to
the Thompson materials. We included some inclusive procedures which tend to
save a bit of time in diagnosing and repairing these items. Post me an
address & I'll forward a copy for your eveluation. However, the Thompson
materials are very good in their coverage however a bit "long-winded". Art
"Jason D." <jpero@sympatico.ca> wrote in message
news:402446a1.9922911@news1.on.sympatico.ca...

On 07 Feb 2004 01:31:35 GMT, jurb6006@aol.com (JURB6006) wrote:

Hi and thanks;

Suggestion, if you don't have the Thompson CD and all the
troubleshooting
information this will turn into a real big dog in a hurry

I do have the CD. What I lack is a training manual. The only thing I can
discern is pin 14 (IIRC) as any kind of clock input, and it has a
varactor
based VCO feeding it. That part of the circuit is working. The Hdrive
output
pin is flat @ 8 volts. Vcc is there etc., I suspect the IC, but when I
found
the whole board was like $32 I ordered it, but I find it NLA (NLA ! ? set
was
built in 2000 !) Our miracle parts guy found one but they're gouging us
$50 for
it. Perhaps they know something we don't ?

If you have training materials for these things you'd be willing to share
with
me they would be greatly appreciated. I'll try to return the favor.

I remember the old CTC169 print had quite a bit of useful info, but I
have
searched the entire DTV306 part of the disk and have found nothing
comparable,
except on the power supply. Even though I am VERY not fond of the Force
software on the NAP CDs, I think I like this even less, if that's
actually
possible. Friggin thing is pointed to drive N: and you can't seem to get
out of
it, I figured out how to get directly to the DWG files and I think I can
find
other progs to open them up.

Thomson's CDs are fine and don't see a problem with them. NAP's
force32 stuff is AWFUL and must get new key every so often from NAP.

Your computer has auto insertion disabled or cd program not run to
install the thing so you can view the schematics. CDs from thomson is
unsecured. Get it installed and working first.

Accessing schematics in my typical repair on RCA goes like this:
insert a RCA cd for that chassis I'm working on. Computer autolaunches
program that displays listings by model, I choose one (either double
click on it or press view button) The program now presents the
default menu. I choose schematics from that menu and then deflection
processing or like that to look at jungle area as if I was working on
DTV306 like you have instead of digging through CD's contents with
exploder.

We have nearly whole range of thomson CDs all the way from CTC17x to
this latest ITCxxx (came out last year). Right now my boss is trying
to get the CD for CTC169 DTV version, already ordered long ago and
credit was charged but no cd. Do have prints for PTV only but this is
not 100% same as DTV version of 169. I get lot of 169'ers to work on
I does need the DTV version on cd. Prints is available but more
expensive.

Training stuff is available both from their website & on CD buy it for
norminal cost. I use it lot, many of these are found on the CDs so I
took use of it to be good at fixing them and understand them better.

Samsung usually & JVC (sometimes) made me chase dogs for long time
because their schematics is good but too little on info (theory of
operation). In Samsung's case I discovered undocumented programming
design in samsung set that reboots if you try to adjust that volume
level but it is "fixed" if I run reset in the service mode (reset is
partial clearing portions of micro's memory contents NOT eeprom!).
Long as that tv was left plugged; turn on and off, play with it is all
day is fine. Then tv is back to bad boy when unplugged then plugged
back in. That was when this "power loss" event data got written into
eeprom, plug tv back in eeprom is read and rest of time eeprom is left
alone and not read or written at all. That part was not typical
design. Thomson's writes & reads eeprom often.

That eeprom's has bad bit in one byte that where volume level info is
read into micro's memory during plug in. Adjusting corrupted volume
info in memory rebooted micro. New eeprom fixed that.

Enjoy your weekend.

Cheers,

Wizard


As much as I'm not really fond of Hitachis, I think they might become the
least
unrecommended new buy. This because you can just DL regular PDFs from
them.
Thompsom really should do that, they're percieved as an American company,
they
have a good market share, their stuff is possible to repair (despite
their best
efforts it sometimes seems) and their CRTs seem to hold up.

Anyway, you can have the soapbox back for now, it's Friday and I am
waiting for
the crowd. It's gonna be pizza time and they will ante up. As far as this
job,
I'll let you know if the board cures it. I would still like to get my
hands on
a training manual for this thing. Might just buy one if nothing else.

I'll send you a seperate email with my real email address soon. I'll use
an
appropriate header so I don't get lost in spam.

Thanks again.

JURB