RE: random monitor flash

["Jose M. Sanchez" <opjose ex-pressnet com>]

What you are experiencing is an input transistor hitting it's "Knee" in an
aberrant manner.

Transistors perform their tasks quickly and identically when certain
conditions are met. These conditions include, temperature, voltage, etc.

If voltages vary (say too much current being sunk to ground, etc.),
temperatures are too high (it's been on for awhile), or just age. The
transistor will no longer function at it's proper trigger point. This will
cause all subsequent circuitry to also fail.

The end result is that for a fraction of a second, your monitor looses all
sync with the signal the computer is outputting.

Lack of signal causes the monitor to go into it's powersave mode, hence the
picture goes black as the monitor attempts to power down.

Some of the quicker acting monitors merely "blink"...

Normally the involved transistor(s) are easy to find because they are
closest to the inputs stages to the monitor... but of course you need either
a wiring diagram, or patience to find the culprit.

This used to be SOOO problematic, that many older and more expensive
monitors were designed with replaceable, ceramic seated transistors for
their input stages...

Fixing one of these merely involved popping in a new set after removing the
cover!

Sadly most newer monitors use soldered-in circuitry... making repairs
difficult...

That said, I've seen monitors exhibit this behavior (especially in the dryer
months where static helps degrade the circuitry or "upsets" things) yet
continue to function for many years... other times I've seen this being the
harbinger of impending failure... changing your video adapter may vary the
signal levels enough to prevent this...

... though your results may vary.

-JMS
opjose ex-pressnet com
"I am not a consultant, I am just from out of town."


-----Original Message-----
From: corey playmore [mailto:plse69me hotmail com]
Sent: Wednesday, February 23, 2000 2:11 PM
To: redhat-install-list redhat com
Subject: random monitor flash



hope someone can help, i searched the sites (obvious with no
luck) and figured i better bother the people who know something
in about there systems.

the prob:
im having a random "thing" happen to where the screen will blank
out on me (blink the color black) for about 2 secs then restore
nothing bad happens but its annoying as heck!

more info: brand new hd,samsung, brand new vcard savage, the monitor
is a ctx vl500 but it didnt have that option just figured the one
up ought to support the olders (used vl700 during installation.)
but i think its the x server??? its set up to s3 gen, s3 is the chipset but
there were to options for the s3 anyways

if anything id like to know where(gnome)/commands (terminal)
for "adjusting these settings." at least i can screw with things
than not do anything at all. ;)

hope someone has time to answer me.