TV with weak colour

[b]

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)]

In article
<d66fed69-3ff3-420b-b891-c50974d9cb8f@k36g2000pri.googlegroups.com>,
b <reverend_rogers@yahoo.com> 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 dave@davenoise.co.uk London SW
To e-mail, change noise into sound.

 

[Arfa Daily]

"b" <reverend_rogers@yahoo.com> wrote in message
news:d66fed69-3ff3-420b-b891-c50974d9cb8f@k36g2000pri.googlegroups.com...

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

 

[Meat Plow]

On Tue, 30 Dec 2008 04:03:46 -0800 (PST), b
<reverend_rogers@yahoo.com>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?

-B

Let's see you say it works WELL but has no/little color?

Get service literature with voltage and video/chroma waveform test
points. Get a DVM and a scope. It's not likely that you'll find the
problem without these basic tools unless you want to heat and cool
components while the set is on the bench live.

 

[b]

On 30 dic 2008, 15:46, "Arfa Daily" <arfa.da...@ntlworld.com> wrote:

"b" <reverend_rog...@yahoo.com> wrote in message

news:d66fed69-3ff3-420b-b891-c50974d9cb8f@k36g2000pri.googlegroups.com...

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]

"b" <reverend_rogers@yahoo.com> wrote in message
news:9a755f12-6546-4a1a-bae1-c6b4342ab351@s1g2000prg.googlegroups.com...

On 30 dic 2008, 15:46, "Arfa Daily" <arfa.da...@ntlworld.com> wrote:
"b" <reverend_rog...@yahoo.com> wrote in message

news:d66fed69-3ff3-420b-b891-c50974d9cb8f@k36g2000pri.googlegroups.com...

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.