Where to get a Toshiba service manual?

[James Sweet]

I'm looking for a service manual or schematic for a TAC9190 chassis, this
seems to be a very uncommon once since I can't locate it anywhere.

Set has a very dark pic, but PIP pic is fine, never seen this problem
before. Have ESR'd virtually every cap in the set and done lots of
resoldering and freeze spray with no change. Suggestions?

 

[ampdoc]

model # please

 

[James Sweet]

model # please

I posted the chassis number, that should be more relevant than the model.
Either way the model is CF3566A.

 

[ampdoc]

Our filing cabinet at work is organized by model. I'll look tomorrow and see
if we have it.
--
Jammy Harbin
J & J Electronics, Inc
227 S. 4Th St.
Selmer, TN 38375
731-645-3311

 

[H. R. Bob Hofmann]

I'm looking for a service manual or schematic for a TAC9190 chassis, this
seems to be a very uncommon once since I can't locate it anywhere.

Set has a very dark pic, but PIP pic is fine, never seen this problem
before. Have ESR'd virtually every cap in the set and done lots of
resoldering and freeze spray with no change. Suggestions?

How do the brightness and contrast controls work, do they have any
effect on the main picture, and do they also affect the PIP? That
might give you a clue as to where the problem is.

If you can find the set in a SAMS photfact index, or look on the back
of the set, you can tell when it was made, and then look at sets mfd
around the same time to get ideas .

H. R. (Bob) Hofmann

 

[James Sweet]

How do the brightness and contrast controls work, do they have any
effect on the main picture, and do they also affect the PIP? That
might give you a clue as to where the problem is.

If you can find the set in a SAMS photfact index, or look on the back
of the set, you can tell when it was made, and then look at sets mfd
around the same time to get ideas .

H. R. (Bob) Hofmann

The brightness and contrast effect the main pic if I remember right, I never
tried to see what they do to the PIP, I'll try that next time I mess with
it.

 

[David]

I have seen that many times a long time ago. As I recall look for an open
resistor that goes between the 120v b+ line and the ABL line sense of the
set. Usually something like a 180K ohm small wattage resistor. I think
they used a 180K and a 120K in series. Without the service manual available
in front of me I cannot give the exact location, but a little looking on the
pcb should find it easily as the abl line off the flyback is always the same
on the Toshiba sets and the main b+ is also usually easy to find.

David

 

[James Sweet]

I have seen that many times a long time ago. As I recall look for an open
resistor that goes between the 120v b+ line and the ABL line sense of the
set. Usually something like a 180K ohm small wattage resistor. I think
they used a 180K and a 120K in series. Without the service manual available
in front of me I cannot give the exact location, but a little looking on the
pcb should find it easily as the abl line off the flyback is always the same
on the Toshiba sets and the main b+ is also usually easy to find.

David

Thanks! That's the first tip I've gotten on this since I first posted about
it. If that fixes it I'll mail you a beer.

 

[James Sweet]

I have seen that many times a long time ago. As I recall look for an open
resistor that goes between the 120v b+ line and the ABL line sense of the
set. Usually something like a 180K ohm small wattage resistor. I think
they used a 180K and a 120K in series. Without the service manual available
in front of me I cannot give the exact location, but a little looking on the
pcb should find it easily as the abl line off the flyback is always the same
on the Toshiba sets and the main b+ is also usually easy to find.

David

Amazing, I've had that set sitting in my garage for almost a year, I've
spent hours poking and prodding with a DMM and Cap Wizard, scouring the
internet for possible solutions and posting on the group numerous times with
zero results and was about to give up but on your tip I found an open
resistor, a stupid little 1/8th watt resistor, which strangely has 4 bands,
green brown orange red, anyway as you said it was in series with another
resistor, 15k in this case. Replaced it with a 51k I had on hand and the
picture came up! 10 years of repairing things as a hobby and this is the
first time I've had such a teeny little single part cause me so much
trouble.

I owe you one!

 

[Jason D.]

Amazing, I've had that set sitting in my garage for almost a year, I've
spent hours poking and prodding with a DMM and Cap Wizard, scouring the
internet for possible solutions and posting on the group numerous times with
zero results and was about to give up but on your tip I found an open
resistor, a stupid little 1/8th watt resistor, which strangely has 4 bands,
green brown orange red, anyway as you said it was in series with another
resistor, 15k in this case. Replaced it with a 51k I had on hand and the
picture came up! 10 years of repairing things as a hobby and this is the
first time I've had such a teeny little single part cause me so much
trouble.

I owe you one!

Bravo...

I have seen several appox 1 year old JVC sets come in with bad SMD
resistors, once had one missing (22KHz, narrow raster).

Remember the RCA SMPS's resistor. Same thing.

Cheers,

Wizard