I have g771 viewsonic monitor. It has been working fine until
just recently. When I cleaned the screen, it looks like it
still has dust on it. I have snooped about the web and in the
newsgroups trying to figure out what is going on.
The G771 is a 17" flat screen monitor from 1998. It appears
to have a flat glass screen treated with an anti-glare
substance in front of the crt face. When I use the monitor's
controls to change the view area size, I end up with a white
border around the 'dusty' area. Peering into the corners and
thru the screen with a flashlight, it appears that there is a
gap between the screen and crt face of perhaps as much as 1/4
of an inch; and that the crt face has dust on it. Perhaps the
seal between the screen and the crt face has deteriorated.
I am wondering if it possible to fix this situation. I can
not find a service manual which addresses the way the tube and
screen are joined. I had read somewhere that the two are
sealed and can be held in place by a steel band, which band is
not supposed to be fiddled with.
I would appreciate any thoughts folk might have. The monitor
works just fine, and with new nvidia drivers for the video
card seems to have regained any lost sharpness, etc.
Thanks in advance.
Be well,
Tim
Old system: <s&g>
Gigabyte G7xe
Duron 1000mhz
500 meg memory
GeForce4 MX 4000
Silicon Image pci ide controller
5 Western Digital hard drives
"Tim" <timmib.nospam@excite.not.com> wrote in message
news:a9KdnbZPnZIp4hvanZ2dnUVZ_uevnZ2d@giganews.com ...
> Greetings,
>
> I have g771 viewsonic monitor. It has been working fine until
> just recently. When I cleaned the screen, it looks like it
> still has dust on it. I have snooped about the web and in the
> newsgroups trying to figure out what is going on.
>
> The G771 is a 17" flat screen monitor from 1998. It appears
> to have a flat glass screen treated with an anti-glare
> substance in front of the crt face. When I use the monitor's
> controls to change the view area size, I end up with a white
> border around the 'dusty' area. Peering into the corners and
> thru the screen with a flashlight, it appears that there is a
> gap between the screen and crt face of perhaps as much as 1/4
> of an inch; and that the crt face has dust on it. Perhaps the
> seal between the screen and the crt face has deteriorated.
>
> I am wondering if it possible to fix this situation. I can
> not find a service manual which addresses the way the tube and
> screen are joined. I had read somewhere that the two are
> sealed and can be held in place by a steel band, which band is
> not supposed to be fiddled with.
>
> I would appreciate any thoughts folk might have. The monitor
> works just fine, and with new nvidia drivers for the video
> card seems to have regained any lost sharpness, etc.
2 things: If you take the monitor apart, leave it to rest for a while before
going near it. A very high voltage builds up on there and it takes a while
to dissipate. If you touch the wrong part, you will blow yourself out of the
building!
Secondly, you have confused me with your last statement - "The monitor works
just fine... ... with new nvidia drivers for the video card seems to have
regained any lost sharpness". If this is true, then what problem remains?
On Thu, 10 Jan 2008 14:27:32 -0600, Tim
<timmib.nospam@excite.not.com> wrote:
>I am wondering if it possible to fix this situation. I can
>not find a service manual which addresses the way the tube and
>screen are joined. I had read somewhere that the two are
>sealed and can be held in place by a steel band, which band is
>not supposed to be fiddled with.
>
Yes it's often a band holding it in, and it isn't supposed
to be fiddled with because you aren't supposed to take apart
a monitor... but if there really is dust between the tube
face and an outer glass sheet then that is what would be
necessary to do.
However, I think you should consider that this monitor is
now 10 years old and ready to be replaced instead of a lot
of work for a monitor ready to die of old age.
"GT" <ContactGT_remove_@hotmail.com> wrote on 11 Jan 2008
>
> 2 things: If you take the monitor apart, leave it to rest
> for a while before going near it. A very high voltage
> builds up on there and it takes a while to dissipate. If
> you touch the wrong part, you will blow yourself out of the
> building!
>
> Secondly, you have confused me with your last statement -
> "The monitor works just fine... ... with new nvidia drivers
> for the video card seems to have regained any lost
> sharpness". If this is true, then what problem remains?
>
>
>
Greetings GT,
Believe me that I do not want to fiddle with the innards! I was
just hoping someone would know if there was a simple seal
between the screen and the crt tube which could be
fixed/replaced after cleaning the crt tube surface. For as it
is now, there is what appears to be a dust layer between the
screen and the crt tube which gives a very light grayish-
brownish caste to everything.
> On Thu, 10 Jan 2008 14:27:32 -0600, Tim
> <timmib.nospam@excite.not.com> wrote:
>
>
>>I am wondering if it possible to fix this situation. I can
>>not find a service manual which addresses the way the tube
>>and screen are joined. I had read somewhere that the two
>>are sealed and can be held in place by a steel band, which
>>band is not supposed to be fiddled with.
>>
>
> Yes it's often a band holding it in, and it isn't supposed
> to be fiddled with because you aren't supposed to take
> apart a monitor... but if there really is dust between the
> tube face and an outer glass sheet then that is what would
> be necessary to do.
>
> However, I think you should consider that this monitor is
> now 10 years old and ready to be replaced instead of a lot
> of work for a monitor ready to die of old age.
Greetings,
I do agree with you in general. The beast is going to be ten
in 6 months. Just hoping to defer the dollar outlay for a bit
.... <s&g>.
Is there any risk that the steel band has become loose - hence
the infiltration - and that the case is actually
holding/reinforcing the tube? Not too excited about pulling
the front of the case off if this were to be the case.
On Fri, 11 Jan 2008 12:21:03 -0600, Tim
<timmib.nospam@excite.not.com> wrote:
>Believe me that I do not want to fiddle with the innards! I was
>just hoping someone would know if there was a simple seal
>between the screen and the crt tube which could be
>fixed/replaced after cleaning the crt tube surface. For as it
>is now, there is what appears to be a dust layer between the
>screen and the crt tube which gives a very light grayish-
>brownish caste to everything.
I would suspect there is nothing sealing the two and that is
why dust eventually got in... but to know for sure you'd
have to start taking it apart. I caution you to first
Google for a safe method of discharging the tube, it will
hold a high voltage charge for awhile, though I don't know
how many days.
I suppose it could instead be that there was a seal like
foam and it just deteriorated over the years and this "dust"
you see is actually particles off the seal.
On Fri, 11 Jan 2008 12:25:53 -0600, Tim
<timmib.nospam@excite.not.com> wrote:
>kony <spam@spam.com> wrote on 11 Jan 2008
>I do agree with you in general. The beast is going to be ten
>in 6 months. Just hoping to defer the dollar outlay for a bit
>... <s&g>.
>
>Is there any risk that the steel band has become loose - hence
>the infiltration - and that the case is actually
>holding/reinforcing the tube? Not too excited about pulling
>the front of the case off if this were to be the case.
I doubt the band became loose, but I can't say it even has
one for certain nor if it did, that this is the cause.
You'd just have to open it and see for yourself.
The case front frame does hold the tube in a *normal* design
(I can't swear 100% of them are like this but offhand I
can't think of any other way it'd be done). The tube needs
no reinforcement but does need the rear board pulled off
carefully so as to not damage it, and the whole think
sitting on the tube/case front so it's sticking straight up
in the air. I'm only giving a brief overview, this is
really beyond the scope of a usenet post, you'd be taking
the whole tube out, cleaning and reassembling later - it is
not a 15 minute job. If there is no seal there is every
reason to think it will get dusty again. If there is a seal
it has degraded to not perform the function and it is not
likely the band holding the tube on just needs tightened or
anything like that, it would more likely be that the seal
has dry rotted over time and needs replaced but I have no
idea if it is a part easily sourced or at a reasonable
price.
On Fri, 11 Jan 2008 12:25:53 -0600, Tim <timmib.nospam@excite.not.com> wrote:
>kony <spam@spam.com> wrote on 11 Jan 2008
>
>> On Thu, 10 Jan 2008 14:27:32 -0600, Tim
>> <timmib.nospam@excite.not.com> wrote:
>>
>>
>>>I am wondering if it possible to fix this situation. I can
>>>not find a service manual which addresses the way the tube
>>>and screen are joined. I had read somewhere that the two
>>>are sealed and can be held in place by a steel band, which
>>>band is not supposed to be fiddled with.
>>>
>>
>> Yes it's often a band holding it in, and it isn't supposed
>> to be fiddled with because you aren't supposed to take
>> apart a monitor... but if there really is dust between the
>> tube face and an outer glass sheet then that is what would
>> be necessary to do.
>>
>> However, I think you should consider that this monitor is
>> now 10 years old and ready to be replaced instead of a lot
>> of work for a monitor ready to die of old age.
>
>Greetings,
>
>I do agree with you in general. The beast is going to be ten
>in 6 months. Just hoping to defer the dollar outlay for a bit
>... <s&g>.
>
>Is there any risk that the steel band has become loose - hence
>the infiltration - and that the case is actually
>holding/reinforcing the tube? Not too excited about pulling
>the front of the case off if this were to be the case.
Tim, be aware that there are TWO dangers when working with big CRTs.
There is, of course, the residual charge from the EHT, which can take hours to
drop to a safe level.
There is also the mechanical energy stored in the almost-perfect vacuum inside,
which is significant with large tubes.
There is nearly 15 pounds of pressure per square inch on the face of the tube.
A big CRT has a lot of square inches - do the math yourself!
IF the glass breaks, some bits of it could fly around.
Always be very careful when a big tube is out of its case.
When I need to work on the inside of a monitor, I rest it face down on the
cushion of an easy chair to avoid damage to the face plate when I remove
the case, because a scratch in the glass would weaken it and increase the
risk of an implosion.
If you must put it on a bench, always put some thick, smooth cushioning under
the glass.
I wouldn't even touch that tension band around the screen...
Strobe <Strobe@nyc.Beep!Beep!.com> wrote on 12 Jan 2008
> Tim, be aware that there are TWO dangers when working with
> big CRTs. There is, of course, the residual charge from the
> EHT, which can take hours to drop to a safe level.
>
> There is also the mechanical energy stored in the
> almost-perfect vacuum inside, which is significant with
> large tubes. There is nearly 15 pounds of pressure per
> square inch on the face of the tube. A big CRT has a lot of
> square inches - do the math yourself! IF the glass breaks,
> some bits of it could fly around.
>
> Always be very careful when a big tube is out of its case.
> When I need to work on the inside of a monitor, I rest it
> face down on the cushion of an easy chair to avoid damage
> to the face plate when I remove the case, because a scratch
> in the glass would weaken it and increase the risk of an
> implosion. If you must put it on a bench, always put some
> thick, smooth cushioning under the glass.
>
> I wouldn't even touch that tension band around the
> screen...
>
>
Greetings,
Yeah ... <s&g> ... I've about convinced myself to pop for a
new monitor. What you've mentioned had well occurred to me.
Was just hoping someone had already tried a fix. ...
Now the question is: Has anyone any experience with AOC crt
displays?
On Sun, 13 Jan 2008 03:59:57 -0600, Tim
<timmib.nospam@excite.not.com> wrote:
>Strobe <Strobe@nyc.Beep!Beep!.com> wrote on 12 Jan 2008
>
>> Tim, be aware that there are TWO dangers when working with
>> big CRTs. There is, of course, the residual charge from the
>> EHT, which can take hours to drop to a safe level.
>>
>> There is also the mechanical energy stored in the
>> almost-perfect vacuum inside, which is significant with
>> large tubes. There is nearly 15 pounds of pressure per
>> square inch on the face of the tube. A big CRT has a lot of
>> square inches - do the math yourself! IF the glass breaks,
>> some bits of it could fly around.
>>
>> Always be very careful when a big tube is out of its case.
>> When I need to work on the inside of a monitor, I rest it
>> face down on the cushion of an easy chair to avoid damage
>> to the face plate when I remove the case, because a scratch
>> in the glass would weaken it and increase the risk of an
>> implosion. If you must put it on a bench, always put some
>> thick, smooth cushioning under the glass.
>>
>> I wouldn't even touch that tension band around the
>> screen...
>>
>>
>
>Greetings,
>
>Yeah ... <s&g> ... I've about convinced myself to pop for a
>new monitor. What you've mentioned had well occurred to me.
>Was just hoping someone had already tried a fix. ...
>
>Now the question is: Has anyone any experience with AOC crt
>displays?
I would not buy a CRT monitor today (but maybe that's just
me, I find LCD the tech is what I had been waiting for, for
so long. I formerly always used Sony Trinitron or
Mitsubishi Diamondtron monitors for my last 3 (over a dozen
years prior to my first LCD)).
As for the tube being fragile, perhaps this is correct but I
never found it a problem. I try to be green (and cheap),
savenging and cannibalizing monitors for various parts
before I throw them (monitors) away and have not had any
problems removing the tension mounting band around the tube
(when present, other times it is not a band just rubber with
a steel clip in each corner) and don't see how one could
easily scratch a tube onto the point of breaking - but I had
the tube resting downward and had an alternate goal, not
reusing the whole monitor.
So basically I'm saying that in my opinion what you propose
can be done ok, given adequate caution, and depending on the
unknown aspect of a gasket material between tube and outer
viewing panel, but is very laborious and being considered
for a monitor already old enough that it's days are
numbered.
Viewsonic monitor problem 
Linear Mode
