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b December 30th 08 12:03 PM

TV with weak colour
 
I have a late '80s vintage Philips CP110 Tv , which works well, but
the colour is weak, even with the saturation control set to full the
picture is only just more 'colourful' than B&W!
.. is this likely to be something like a low voltage to the RGB
stage,or something more serious?

-B

Dave Plowman (News) December 30th 08 01:19 PM

TV with weak colour
 
In article
,
b wrote:
I have a late '80s vintage Philips CP110 Tv , which works well, but
the colour is weak, even with the saturation control set to full the
picture is only just more 'colourful' than B&W!
. is this likely to be something like a low voltage to the RGB
stage,or something more serious?


What happens if you drive it with an RGB signal?

--
*Always borrow money from pessimists - they don't expect it back *

Dave Plowman London SW
To e-mail, change noise into sound.

Arfa Daily December 30th 08 02:46 PM

TV with weak colour
 

"b" wrote in message
...
I have a late '80s vintage Philips CP110 Tv , which works well, but
the colour is weak, even with the saturation control set to full the
picture is only just more 'colourful' than B&W!
. is this likely to be something like a low voltage to the RGB
stage,or something more serious?

-B


If the A1 control is set wrongly, some of the older CRT types can look
'washed out'. Sometimes, beam limiter problems can give the same effect. A
fault in the ACC circuitry will do it, and sometimes, a mishapen sandcastle
pulse, which used to be quite common back then. Often down to a resistor in
the HOP stage, where the pulse is 'constructed', having gone high.

Arfa



b February 2nd 09 01:02 AM

TV with weak colour
 
On 30 dic 2008, 15:46, "Arfa Daily" wrote:
"b" wrote in message

...

I have a late '80s vintage Philips CP110 Tv , which works well, but
the colour is weak, even with the saturation control set to full the
picture is only just more 'colourful' than B&W!
. is this likely to be something like a low voltage to the RGB
stage,or something more serious?


-B


If the A1 control is set wrongly, some of the older CRT types can look
'washed out'. Sometimes, beam limiter problems can give the same effect. A
fault in the ACC circuitry will do it, and sometimes, a mishapen sandcastle
pulse, which used to be quite common back then. Often down to a resistor in
the HOP stage, where the pulse is 'constructed', having gone high.

Arfa


I finally dug this set out again today and it did seem as if the G2
was a bit high, so I lowered the SCREEN control slightly on the Line o/
p tranny and that gave a far more natural colour. Haven't tried it
with RGB source, as didn't have one to hand. set seems fine now ,
cheers,
B.

Farmer Giles[_2_] February 2nd 09 12:10 PM

TV with weak colour
 

"b" wrote in message
...
On 30 dic 2008, 15:46, "Arfa Daily" wrote:
"b" wrote in message

...

I have a late '80s vintage Philips CP110 Tv , which works well, but
the colour is weak, even with the saturation control set to full the
picture is only just more 'colourful' than B&W!
. is this likely to be something like a low voltage to the RGB
stage,or something more serious?


-B


If the A1 control is set wrongly, some of the older CRT types can look
'washed out'. Sometimes, beam limiter problems can give the same effect.
A
fault in the ACC circuitry will do it, and sometimes, a mishapen
sandcastle
pulse, which used to be quite common back then. Often down to a resistor
in
the HOP stage, where the pulse is 'constructed', having gone high.

Arfa


I finally dug this set out again today and it did seem as if the G2
was a bit high, so I lowered the SCREEN control slightly on the Line o/
p tranny and that gave a far more natural colour. Haven't tried it
with RGB source, as didn't have one to hand. set seems fine now ,
cheers,
B.


I'm not familiar with the model - and slightly out of touch with TVs in
general - but having considerable experience in TV service in the distant
past, I can tell you that colour saturation has nothing to do with A1 or A2
controls - which only affect brightness or 'grey-scale' settings. Look for
the chrominance amplifier circuitry, that is where the problem is likely to
be.




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