Hi.

I have 15" CRT monitor VISION DX-1564 (~1998), operating at 1024x768.
It supports refresh rate of up to 75Hz at 1024x768 and 60Hz at 1280x1024.

I wish to use 75Hz refresh, but when I put 75Hz refresh rate, the image
has very bright lines. When I put 70Hz the image is good.

What can be causing this problem?
The monitor is connect to S3 video card.

[]s
--
Chaos Master®, posting from Canoas, Brazil - 29.55° S / 51.11° W (GMT -2
(BRST) / GMT -3 (BRT))

"Two of the most famous products of Berkeley are LSD and Unix. I don't
think that this is a coincidence." -- Anonymous

On Tue, 14 Dec 2004 00:20:41 -0200, Chaos Master
put finger to keyboard and composed:

I have 15" CRT monitor VISION DX-1564 (~1998), operating at 1024x768.
It supports refresh rate of up to 75Hz at 1024x768 and 60Hz at 1280x1024.

I wish to use 75Hz refresh, but when I put 75Hz refresh rate, the image
has very bright lines.

Do you mean retrace lines?


- Franc Zabkar
--
Please remove one 's' from my address when replying by email.

On Tue, 14 Dec 2004 00:20:41 -0200, Chaos Master
wrote:

Hi.

I have 15" CRT monitor VISION DX-1564 (~1998), operating at 1024x768.
It supports refresh rate of up to 75Hz at 1024x768 and 60Hz at 1280x1024.

I wish to use 75Hz refresh, but when I put 75Hz refresh rate, the image
has very bright lines. When I put 70Hz the image is good.

What can be causing this problem?
The monitor is connect to S3 video card.

[]s
--
Chaos Master®, posting from Canoas, Brazil - 29.55° S / 51.11° W (GMT -2
(BRST) / GMT -3 (BRT))

"Two of the most famous products of Berkeley are LSD and Unix. I don't
think that this is a coincidence." -- Anonymous

Get an engineer to slightly turn down the flyback screen control to
see if will adjust it,it should.

(Harry Hotspur) writes:

On Tue, 14 Dec 2004 00:20:41 -0200, Chaos Master
wrote:

Hi.

I have 15" CRT monitor VISION DX-1564 (~1998), operating at 1024x768.
It supports refresh rate of up to 75Hz at 1024x768 and 60Hz at 1280x1024.

I wish to use 75Hz refresh, but when I put 75Hz refresh rate, the image
has very bright lines. When I put 70Hz the image is good.

What can be causing this problem?
The monitor is connect to S3 video card.

Get an engineer to slightly turn down the flyback screen control to
see if will adjust it,it should.

If it happened suddenly, it's not an adjustment but a power supply,
deflection, or video problem. IF you adjust the screen/G2 control,
it will probably mess up other refresh rates making them too dark, and
is likely just masking some other problem.

--- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/
Repair | Main Table of Contents: http://repairfaq.ece.drexel.edu/REPAIR/
+Lasers | Sam's Laser FAQ: http://repairfaq.ece.drexel.edu/sam/lasersam.htm
| Mirror Sites: http://repairfaq.ece.drexel.edu/REPAIR/F_mirror.html

Note: These links are hopefully temporary until we can sort out the excessive
traffic on Repairfaq.org.

Important: Anything sent to the email address in the message header is ignored.
To contact me, please use the Feedback Form in the FAQs.

"Harry Hotspur" wrote in message
...
On Tue, 14 Dec 2004 00:20:41 -0200, Chaos Master
wrote:

Hi.

I have 15" CRT monitor VISION DX-1564 (~1998), operating at 1024x768.
It supports refresh rate of up to 75Hz at 1024x768 and 60Hz at 1280x1024.

I wish to use 75Hz refresh, but when I put 75Hz refresh rate, the image
has very bright lines. When I put 70Hz the image is good.

What can be causing this problem?
The monitor is connect to S3 video card.

[]s
--
Chaos Master®, posting from Canoas, Brazil - 29.55° S / 51.11° W (GMT -2
(BRST) / GMT -3 (BRT))

"Two of the most famous products of Berkeley are LSD and Unix. I don't
think that this is a coincidence." -- Anonymous

Get an engineer to slightly turn down the flyback screen control to
see if will adjust it,it should.

That's not a fix, he said it's brighter at a higher refresh rate, which is
unusual, normally it becomes darker. Did the problem happen gradually? Does
it change at all as the monitor warms up? If so I suspect a capacitor is
failing, if it happened suddenly then I'd look for a cracked solder joint
around the HV section or a shorted transistor in the regulator.

On Tue, 14 Dec 2004 18:08:14 GMT, (Harry
Hotspur) put finger to keyboard and composed:

On Tue, 14 Dec 2004 00:20:41 -0200, Chaos Master
wrote:

Hi.

I have 15" CRT monitor VISION DX-1564 (~1998), operating at 1024x768.
It supports refresh rate of up to 75Hz at 1024x768 and 60Hz at 1280x1024.

I wish to use 75Hz refresh, but when I put 75Hz refresh rate, the image
has very bright lines. When I put 70Hz the image is good.

What can be causing this problem?
The monitor is connect to S3 video card.

[]s
--
Chaos Master®, posting from Canoas, Brazil - 29.55° S / 51.11° W (GMT -2
(BRST) / GMT -3 (BRT))

"Two of the most famous products of Berkeley are LSD and Unix. I don't
think that this is a coincidence." -- Anonymous

Get an engineer to slightly turn down the flyback screen control to
see if will adjust it,it should.

I wonder if the EHT rises too high at the 75Hz refresh rate. It could
be that the different line rates call for different tuning caps, one
of which may be slightly open, causing the flyback pulses at the
collector of the HOT to rise too high, which in turn would cause the
EHT to increase.


- Franc Zabkar
--
Please remove one 's' from my address when replying by email.

Hi!

I have 15" CRT monitor VISION DX-1564 (~1998), operating at 1024x768.
It supports refresh rate of up to 75Hz at 1024x768 and 60Hz at 1280x1024.

When you run a a monitor at the maximum supported scan rate for a given
resolution, you may find that it doesn't always run well, especially when
you get to the upper ends of the monitor's abilities. Sometimes that is just
the way it is--other times the monitor may have worn components that can't
handle what they once were designed for.

Have you checked to see what happens at 75Hz in lower resolutions?

What can be causing this problem?
The monitor is connect to S3 video card.

The video card shouldn't be a factor in this, so long as it basically works.
I have here a Trio64V2 with 2MB VRAM running a cheap-o Dell 17 inch monitor
at 1024x768/75Hz vertical. I didn't know that those early S3 video chips
were capable of that high a scan rate, but it will go to 85Hz if I select
that.

William

On 14 Dec 2004 13:33:54 -0500, Sam Goldwasser
wrote:

(Harry Hotspur) writes:

On Tue, 14 Dec 2004 00:20:41 -0200, Chaos Master
wrote:

Hi.

I have 15" CRT monitor VISION DX-1564 (~1998), operating at 1024x768.
It supports refresh rate of up to 75Hz at 1024x768 and 60Hz at 1280x1024.

I wish to use 75Hz refresh, but when I put 75Hz refresh rate, the image
has very bright lines. When I put 70Hz the image is good.

What can be causing this problem?
The monitor is connect to S3 video card.

Get an engineer to slightly turn down the flyback screen control to
see if will adjust it,it should.

If it happened suddenly, it's not an adjustment but a power supply,
deflection, or video problem. IF you adjust the screen/G2 control,
it will probably mess up other refresh rates making them too dark, and
is likely just masking some other problem.

--- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/
Repair | Main Table of Contents: http://repairfaq.ece.drexel.edu/REPAIR/
+Lasers | Sam's Laser FAQ: http://repairfaq.ece.drexel.edu/sam/lasersam.htm
| Mirror Sites: http://repairfaq.ece.drexel.edu/REPAIR/F_mirror.html

Note: These links are hopefully temporary until we can sort out the excessive
traffic on Repairfaq.org.

Important: Anything sent to the email address in the message header is ignored.
To contact me, please use the Feedback Form in the FAQs.

I wasn't aware he said it happened suddenly,diffence between 70 Hz and
75HZ is small.I know the screen control may have a problem,a small
tweak on the flyback pot should not mess up other refresh rates to any
extent.As you know it's a very fine adj.to blank out retrace lines,if
he wants to run on his said 1024x768 I think the result will be
sufficient for most people,coupled with brightness and contrast
control.
If he wants to go into employing us to check out all the screen feeds
then it's cheaper to buy another monitor as it is 15" and 6 years
old.Just trying to advise a cheap remedy for him.

Franc Zabkar squeaks:

I have 15" CRT monitor VISION DX-1564 (~1998), operating at 1024x768.
It supports refresh rate of up to 75Hz at 1024x768 and 60Hz at 1280x1024.

I wish to use 75Hz refresh, but when I put 75Hz refresh rate, the image
has very bright lines.

Do you mean retrace lines?

OK, most likely, I didn't knew the term in English.
--
Chaos Master®, posting from Canoas, Brazil - 29.55° S / 51.11° W

"People told me I can't dress like a fairy.
I say, I'm in a rock band and I can do what the hell I want!"
-- Amy Lee

NOTE: messages are automatically sent after 00:00AM! I'm on dial-up!

NP: nothing (Winamp is stopped)

James Sweet squeaks:

Get an engineer to slightly turn down the flyback screen control to
see if will adjust it,it should.

That's not a fix, he said it's brighter at a higher refresh rate, which is
unusual, normally it becomes darker. Did the problem happen gradually? Does
it change at all as the monitor warms up? If so I suspect a capacitor is
failing, if it happened suddenly then I'd look for a cracked solder joint
around the HV section or a shorted transistor in the regulator.

Doesn't change as monitor warm up. But I will have to check for those
failed components as the monitor is old and suffered some heavy usage.

[]s
--
Chaos Master®, posting from Canoas, Brazil - 29.55° S / 51.11° W

"People told me I can't dress like a fairy.
I say, I'm in a rock band and I can do what the hell I want!"
-- Amy Lee

NOTE: messages are automatically sent after 00:00AM! I'm on dial-up!

NP: Lacuna Coil - Heaven's A Lie

William R. Walsh squeaks:

When you run a a monitor at the maximum supported scan rate for a given
resolution, you may find that it doesn't always run well, especially when
you get to the upper ends of the monitor's abilities. Sometimes that is just
the way it is--other times the monitor may have worn components that can't
handle what they once were designed for.

Maybe this is the problem, this monitor is cheap monitor, maybe it was
designed without 75Hz in mind?

Have you checked to see what happens at 75Hz in lower resolutions?

The image is good on 800x600@75Hz.

What can be causing this problem?
The monitor is connect to S3 video card.

The video card shouldn't be a factor in this, so long as it basically works.
I have here a Trio64V2 with 2MB VRAM running a cheap-o Dell 17 inch monitor
at 1024x768/75Hz vertical. I didn't know that those early S3 video chips
were capable of that high a scan rate, but it will go to 85Hz if I select
that.

I know, but I just put this for completeness.
--
Chaos Master®, posting from Canoas, Brazil - 29.55° S / 51.11° W

"People told me I can't dress like a fairy.
I say, I'm in a rock band and I can do what the hell I want!"
-- Amy Lee

NOTE: messages are automatically sent after 00:00AM! I'm on dial-up!

NP: Lacuna Coil - When A Dead Man Walks

Harry Hotspur exposed:

I wasn't aware he said it happened suddenly,diffence between 70 Hz and
75HZ is small.I know the screen control may have a problem,a small
tweak on the flyback pot should not mess up other refresh rates to any
extent.As you know it's a very fine adj.to blank out retrace lines,if
he wants to run on his said 1024x768 I think the result will be
sufficient for most people,coupled with brightness and contrast
control.

I will use 70Hz for a while, until I buy a LCD monitor (in 6 months or
so), maybe then I will leave this monitor for usage as 2nd monitor.

[]s
--
Chaos Master®, posting from Canoas, Brazil - 29.55° S / 51.11° W

"People told me I can't dress like a fairy.
I say, I'm in a rock band and I can do what the hell I want!"
-- Amy Lee

NOTE: messages are automatically sent after 00:00AM! I'm on dial-up!

Hi!

Maybe this is the problem, this monitor is cheap monitor, maybe it was
designed without 75Hz in mind?

It's certainly very possible. I've seen a lot of monitors that didn't run
well close to their limits.

There's one line of 14/15 inch monitor that sticks out though--some
Sampo-made Dell Ultrascan displays. These were great monitors in my
experience. Every one of them I had would run 75Hz at 1024x768 with no
problems and 85Hz at 800x600. There were only a few weak points--these
monitors needed some new capacitors after a few years and the signal cables
were easy to break. Other than that these were nice basic monitors with good
pictures.

You might see if you could find one.

The image is good on 800x600@75Hz.

Almost certainly a weakness of the monitor or getting close to its limits.
This behavior could indicate a minor problem developing, but until the
behavior gets worse, it would be hard to say.

I know, but I just put this for completeness.

Same thing here. Just wanted you to know what I've used here.

William