color adustments do only one at time (sony pvm-8220)
 

I got this sony pvm-8220 from a thrift shop and it was only black and
white when setup. There are two set of RGB adjustments in the back
that is easily accessible. But any adjustments results in either a
red, blue or green picture. (red and white, or blue and white and
etc.) Neither the tint or color knobs have any affects either while
the others work. I don,t know if this is a simple issue or complex
enough to end up in a thrift shop. That would be a start for me.

color adustments do only one at time (sony pvm-8220)
 

"NN" bravely wrote to "All" (17 Oct 05 18:51:05)
--- on the heady topic of "color adustments do only one at time (sony pvm-8220)"

NN From: "NN"
NN Xref: core-easynews sci.electronics.repair:345546

NN I got this sony pvm-8220 from a thrift shop and it was only black and
NN white when setup. There are two set of RGB adjustments in the back
NN that is easily accessible. But any adjustments results in either a
NN red, blue or green picture. (red and white, or blue and white and
NN etc.) Neither the tint or color knobs have any affects either while
NN the others work. I don,t know if this is a simple issue or complex
NN enough to end up in a thrift shop. That would be a start for me.


Could be a bad video processor IC. The lack of colour might mean the
colour info or reference isn't being demodulated. Maybe a bad crystal.
Perhaps someone played with the screws in the little cans. It might be
a tuner afc problem. Might be a bad contact for the colour control on
the main board, etc. More things can cause a loss of colour. It will
require good signal tracing and diagnostic skills. Are you savvy?

A*s*i*m*o*v

.... The first rule of intelligent tinkering is to save all the parts.

color adustments do only one at time (sony pvm-8220)
 

"NN" wrote in message
oups.com...
I got this sony pvm-8220 from a thrift shop and it was only black and
white when setup. There are two set of RGB adjustments in the back
that is easily accessible. But any adjustments results in either a
red, blue or green picture. (red and white, or blue and white and
etc.)

You shouldn't have touched those adjustments, they are irrelevent to your
problem. Did you mark them so you can return them to their original
settings?

Neither the tint or color knobs have any affects either while
the others work. I don,t know if this is a simple issue or complex
enough to end up in a thrift shop. That would be a start for me.



Look around the chroma processing circuitry. However, unless you are
familiar with the operation of chroma processing circuitry, you won't get
anywhere. You could check for dry joints, but that's about it I'm afraid.
Don't be tempted to start fiddling with settings, there is a fault which
needs repairing, and misaligning settings in the hope of sorting it out will
add to your problems.

If it's any help, I've known the crystals and trimmers in the chroma circuit
go bad in certain Sonys.

Dave

color adustments do only one at time (sony pvm-8220)
 

On 17 Oct 2005 18:51:05 -0700, "NN" wrote:

I got this sony pvm-8220 from a thrift shop and it was only black and
white when setup. There are two set of RGB adjustments in the back
that is easily accessible. But any adjustments results in either a
red, blue or green picture. (red and white, or blue and white and
etc.) Neither the tint or color knobs have any affects either while
the others work. I don,t know if this is a simple issue or complex
enough to end up in a thrift shop. That would be a start for me.


The common problem causing no color for this model is the varicap in
the color circuit. They go bad all the time. You can adjust it and
the color will come back but it will drift out again. It is located
at the lower right of the board when viewing it from the front. It is
available from Sony parts and costs under $5.00. Chuck

color adustments do only one at time (sony pvm-8220)
 

This sounds like a solution I can afford. I will have to readjust the
color boxes I moved around. You don,t know how to get to sony parts
online? I find sony stuff really hard to find on the web besides
regular consumer stuff at the store.

color adustments do only one at time (sony pvm-8220)
 

"NN" wrote in message
ups.com...
This sounds like a solution I can afford. I will have to readjust the
color boxes I moved around. You don,t know how to get to sony parts
online? I find sony stuff really hard to find on the web besides
regular consumer stuff at the store.


You can probably order it online from sony.com, I know Pioneer works that
way, for parts that is, not whole units.

color adustments do only one at time (sony pvm-8220)
 

"NN" wrote in message
ups.com...
This sounds like a solution I can afford. I will have to readjust the
color boxes I moved around. You don,t know how to get to sony parts
online? I find sony stuff really hard to find on the web besides
regular consumer stuff at the store.



Don't ask for a varicap though, that is an entirely different device. The
part is a 'variable capacitor'.

Dave

color adustments do only one at time (sony pvm-8220)
 

On Wed, 19 Oct 2005 13:18:37 +0100, "Dave D"
wrote:


"NN" wrote in message
oups.com...
This sounds like a solution I can afford. I will have to readjust the
color boxes I moved around. You don,t know how to get to sony parts
online? I find sony stuff really hard to find on the web besides
regular consumer stuff at the store.



Don't ask for a varicap though, that is an entirely different device. The
part is a 'variable capacitor'.

Dave

Thanks Dave. I must be going senile. Chuck

color adustments do only one at time (sony pvm-8220) Part no. of trimmer
 

On Wed, 19 Oct 2005 13:52:09 GMT, Chuck wrote:

On Wed, 19 Oct 2005 13:18:37 +0100, "Dave D"
wrote:


"NN" wrote in message
roups.com...
This sounds like a solution I can afford. I will have to readjust the
color boxes I moved around. You don,t know how to get to sony parts
online? I find sony stuff really hard to find on the web besides
regular consumer stuff at the store.



Don't ask for a varicap though, that is an entirely different device. The
part is a 'variable capacitor'.

Dave

Thanks Dave. I must be going senile. Chuck


Here is the Sony part no. for the trimmer cap. 1-141-245-00

color adustments do only one at time (sony pvm-8220)
 

"Chuck" wrote in message
...

Thanks Dave. I must be going senile. Chuck


That makes three of us! I mean two of us...

:-)

Dave

color adustments do only one at time (sony pvm-8220)
 

Thanks to both Chuck and Dave. I have soldering and take apart skills
and no tv knowledge beside safety issues with CRT and capacitors. The
part number is perfect for me to do the job.

David

color adustments do only one at time (sony pvm-8220) Part no. of trimmer
 

The order went smoothly with your help (actually step by step
directions) and the total was less than 6 dollars!

Now I would have never found the part because I tried to find it my way
by using their model number option and got no results.

color adustments do only one at time (sony pvm-8220)
 

"NN" wrote in message
ups.com...
Thanks to both Chuck and Dave. I have soldering and take apart skills
and no tv knowledge beside safety issues with CRT and capacitors. The
part number is perfect for me to do the job.

David



The best of luck with the repair. If it fails, at least you haven't spent a
large amount of money on it! With the absence of proper test equipment and
service manuals, you'll have to play around with the new variable capacitor
to get the right setting. TBH, it's good enough except perhaps for a
commercial outfit / dealer with strict procedures ;-) You'll know when you
get it right.

If it still doesn't work, then you are left with the problem of what to do
next. You could try replacing the crystal, but there'll come a time when
buying parts on the offchance they'll cure the fault will cease to be cost
effective. I think the new part will fix the problem though as it was a
common falure.

Dave

color adustments do only one at time (sony pvm-8220)
 

I can always leave it alone as a black and white if all else fails. It
is interesting to note that everything else works great and even the
blue screen works. No wonder it was at the thrift shop.

David

color adustments do only one at time (sony pvm-8220)
 

"NN" wrote in message
oups.com...
I can always leave it alone as a black and white if all else fails. It
is interesting to note that everything else works great and even the
blue screen works. No wonder it was at the thrift shop.



Does it have a scart socket or RGB inputs on the back? If so, you can input
an RGB signal and you'll get colour. ie, a satellite or terrestrial digital
TV decoder with an RGB output can be connected to your TV and you'll get a
colour picture as RGB does not use the chroma decoder circuitry in the TV.

Dave

got the part but don,t know where to look (sony pvm-8220)
 

Dave D wrote:
"NN" wrote in message
oups.com...
I can always leave it alone as a black and white if all else fails. It
is interesting to note that everything else works great and even the
blue screen works. No wonder it was at the thrift shop.



Does it have a scart socket or RGB inputs on the back? If so, you can input
an RGB signal and you'll get colour. ie, a satellite or terrestrial digital
TV decoder with an RGB output can be connected to your TV and you'll get a
colour picture as RGB does not use the chroma decoder circuitry in the TV.

Dave
All it has is two BNC (I use a rca adapter) in and out with a rf switch
for 75ohms and some other input labeled tally.

I got my part but I don,t know if it is covered by one of the external
control knobs or where to look. The tv is put together like sony
always does, modular boards all around.

The part is green, is that a standard to look for ? all they usually
green?

Thanks Again

David

got the part but don,t know where to look (sony pvm-8220)
 

to make clear, the rf switch is part of the monitor, not being used by
me since I input from a vcr video out.