JVC TV No red Color

M

max

Guest
Hi
I have JVC TV model AV-27D303.Green and Blue is Ok no Red color.I was
checked Video amps transistors on CRT board.It looks good.Voltage on Rk goes
240V instead 160V as on Gk and Bk.
Suspected IC 201 TOSHIBA 8812CSDNG3U68 which was replaced but problem still
exist.

Any suggestions?

Thanks
 
Compare the bias volts to the tube elements between all the colour
channels. If these are very close, then check that there is video
drive at proper specs going from the outputs of the video amps to the
CRT.

If all this complies, then you have a bad CRT.

Jerry Greenberg
http://www.zoom-one.com

--

"max" <mxgl@cwnet.com> wrote in message news:<106u2gkm4fo4i6b@corp.supernews.com>...
Hi
I have JVC TV model AV-27D303.Green and Blue is Ok no Red color.I was
checked Video amps transistors on CRT board.It looks good.Voltage on Rk goes
240V instead 160V as on Gk and Bk.
Suspected IC 201 TOSHIBA 8812CSDNG3U68 which was replaced but problem still
exist.

Any suggestions?

Thanks
Click to expand...
 
On 3 Apr 2004 15:16:29 -0800, jerryg50@hotmail.com (Jerry Greenberg)
wrote:

Compare the bias volts to the tube elements between all the colour
channels. If these are very close, then check that there is video
drive at proper specs going from the outputs of the video amps to the
CRT.

If all this complies, then you have a bad CRT.

Jerry Greenberg
http://www.zoom-one.com
Click to expand...
Whoa!

This fooled me, went far as changed a CRT on those JVC newer chassis
even changed that super jungle! The problem was in the CRT board SMD
resistors. Some had bad solder connection or one bad resistor. Check
those! With meter and do a resoldering on those if you can't see
anything look bad solder.

The bias voltage will looks close but is still wrong.

So far I seen about 4 of this after this initial incident, recent one
was last week. :-O

Summary: Check the CRT board for any bad part, duff resistor or bad
solder joint (redo solder just the affected color).

Cheers,

Wizard
 
I have seen two of these also. A 150 ohm resistor feeding signal from the
jungle IC to the base of the red output transistor, and a 270 ohm from the
emitter to ground. If only one checks bad, replace the other also as it's
likely to go soon after.

-Woodie

"Jason D." <jpero@sympatico.ca> wrote in message
news:406f71b3.7508542@news1.on.sympatico.ca...
On 3 Apr 2004 15:16:29 -0800, jerryg50@hotmail.com (Jerry Greenberg)
wrote:

Compare the bias volts to the tube elements between all the colour
channels. If these are very close, then check that there is video
drive at proper specs going from the outputs of the video amps to the
CRT.

If all this complies, then you have a bad CRT.

Jerry Greenberg
http://www.zoom-one.com

Whoa!

This fooled me, went far as changed a CRT on those JVC newer chassis
even changed that super jungle! The problem was in the CRT board SMD
resistors. Some had bad solder connection or one bad resistor. Check
those! With meter and do a resoldering on those if you can't see
anything look bad solder.

The bias voltage will looks close but is still wrong.

So far I seen about 4 of this after this initial incident, recent one
was last week. :-O

Summary: Check the CRT board for any bad part, duff resistor or bad
solder joint (redo solder just the affected color).

Cheers,

Wizard
Click to expand...
 
thats what I suspected too I replaced one resistor for 15 Om some resistors
not installed by manufacture.Today I will check resistor between 270 Om and
emitter.Thanks for suggestions guys.
"Woodie Morris" <woodie7@comcast.net> wrote in message
news:D8GdnT8C1bEGHPLdRVn-uQ@comcast.com...
I have seen two of these also. A 150 ohm resistor feeding signal from the
jungle IC to the base of the red output transistor, and a 270 ohm from
the
emitter to ground. If only one checks bad, replace the other also as it's
likely to go soon after.

-Woodie

"Jason D." <jpero@sympatico.ca> wrote in message
news:406f71b3.7508542@news1.on.sympatico.ca...
On 3 Apr 2004 15:16:29 -0800, jerryg50@hotmail.com (Jerry Greenberg)
wrote:

Compare the bias volts to the tube elements between all the colour
channels. If these are very close, then check that there is video
drive at proper specs going from the outputs of the video amps to the
CRT.

If all this complies, then you have a bad CRT.

Jerry Greenberg
http://www.zoom-one.com

Whoa!

This fooled me, went far as changed a CRT on those JVC newer chassis
even changed that super jungle! The problem was in the CRT board SMD
resistors. Some had bad solder connection or one bad resistor. Check
those! With meter and do a resoldering on those if you can't see
anything look bad solder.

The bias voltage will looks close but is still wrong.

So far I seen about 4 of this after this initial incident, recent one
was last week. :-O

Summary: Check the CRT board for any bad part, duff resistor or bad
solder joint (redo solder just the affected color).

Cheers,

Wizard
Click to expand...
 
Thanks guys for your help.Resistor between emitter and ground was bad.27 Om
on meter shows me 3.2kOm.Replace it back on 27Om return the red color back.

"max" <mxgl@cwnet.com> wrote in message
news:1070qqvlune9be4@corp.supernews.com...
thats what I suspected too I replaced one resistor for 15 Om some
resistors
not installed by manufacture.Today I will check resistor between 270 Om
and
emitter.Thanks for suggestions guys.
"Woodie Morris" <woodie7@comcast.net> wrote in message
news:D8GdnT8C1bEGHPLdRVn-uQ@comcast.com...
I have seen two of these also. A 150 ohm resistor feeding signal from
the
jungle IC to the base of the red output transistor, and a 270 ohm from
the
emitter to ground. If only one checks bad, replace the other also as
it's
likely to go soon after.

-Woodie

"Jason D." <jpero@sympatico.ca> wrote in message
news:406f71b3.7508542@news1.on.sympatico.ca...
On 3 Apr 2004 15:16:29 -0800, jerryg50@hotmail.com (Jerry Greenberg)
wrote:

Compare the bias volts to the tube elements between all the colour
channels. If these are very close, then check that there is video
drive at proper specs going from the outputs of the video amps to
the
CRT.

If all this complies, then you have a bad CRT.

Jerry Greenberg
http://www.zoom-one.com

Whoa!

This fooled me, went far as changed a CRT on those JVC newer chassis
even changed that super jungle! The problem was in the CRT board SMD
resistors. Some had bad solder connection or one bad resistor. Check
those! With meter and do a resoldering on those if you can't see
anything look bad solder.

The bias voltage will looks close but is still wrong.

So far I seen about 4 of this after this initial incident, recent one
was last week. :-O

Summary: Check the CRT board for any bad part, duff resistor or bad
solder joint (redo solder just the affected color).

Cheers,

Wizard
Click to expand...
 
On Sun, 4 Apr 2004 20:18:50 -0700, "max" <mxgl@cwnet.com> wrote:

Thanks guys for your help.Resistor between emitter and ground was bad.27 Om
on meter shows me 3.2kOm.Replace it back on 27Om return the red color back.
Click to expand...
Max,

You're welcome!

Jerry gave good advices but I sometimes have hard time reading what
he's implying at.

Cheers,

Wizard
 
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