Maker Pro
Maker Pro

Dell Trinitron 17" flaky - worth repairing?

V

Van Chocstraw

Jan 1, 1970
0
I've got a Dell Ultrascan 1000HS Model D1025TM that was manufactured in
May of 1998. It's quite similar to the Sony CPD-200GS (17" Trinitron
tube) without the audio. I'm the original owner and have had no
problems with it for 7 years until last week. The picture was fine, no
shaking, no blurriness, warm-up time around 20 sec., no dimness, no
strange sounds, nothing. It was perfectly fine.

All of a sudden last week I turned it on one day and after about 10
minutes the screen went black. There was no change in the picture
before this happened. At the same time the picture went black the green
light on the power button also went out. It didn't change to amber, or
start blinking. I did hear a relay click out, as is normal when you
shut it off.

About 3 or 4 seconds after going black, it seemed to go into its initial
power-on startup sequence again. The degaussing relay kicked in, I
heard the static hum, then the other realy clicked, the green light on
the power button came on, the degaussing relay dropped out and it seemed
to be warming up again. But instead of completing the startup sequence,
after about 5 seconds the green light went out again and I heard the
relay click out again. This cycle then repeats itself over and over.
At power-on, 3 relay clicks and the light comes on, then after a few
seconds the green light goes out simultaneously with a relay click.
Lather, rinse, repeat.

If left off for an hour or so it will power on normally and display its
usual crisp, clear picture. There are absolutely no defects in the
picture. Brightness, contrast, changing screen resolutions on the PC
(800x600, 1024x768, 640x480) all work normally and the picture is fine.
But after it warms up, *click* and the light goes out and the
startup-shutdown cycle starts again.

I unplugged the video cable from the PC to see how the power-on
self-test would go and it came up normally with the "No Video Signal"
message and the color bars, so that test passed.

I'm trying to decide what to do. In a past life I've done a little
soldering on a TV set or two (15 years ago) and I have the service
manual for it. Does the problem sound familiar to anybody? If it was
something like a cold solder joint I could probably remove the boards
safely and inspect them. Or, I could take it to a repair shop where I'm
guessing a repair might run around $100 or so. Or I could order a
refurb unit (same model) from a place I found online for $100 shipped
with a 90-day warranty. Or I could buy a closeout (but still new)
Viewsonic PF77 for $125 shipped.

I'm not ready to make the leap into an LCD panel yet. Good ones are
still relatively expensive, and there's no such thing as an all-purpose
LCD panel. The LCD that does everything I need it to do hasn't been
built yet for under $600.

I know in my head the new Viewsonic is probably the way to go, but in my
heart I hate to throw the Ultrascan out, especially since it appears, at
least to me, like the problem might be very easy to fix. As I said, the
picture is still bright, clear, and rock solid when it's on. I would
appreciate any advice or tips from those who know more about these
things than I do. I can't keep staring at this _really_ old and blurry
MultiSync 3D for much longer. My eyes are bad enough.

Thanks in advance,
VCS
 
D

Dave D

Jan 1, 1970
0
Van Chocstraw said:
I've got a Dell Ultrascan 1000HS Model D1025TM that was manufactured in
May of 1998. It's quite similar to the Sony CPD-200GS (17" Trinitron
tube) without the audio. I'm the original owner and have had no problems
with it for 7 years until last week. The picture was fine, no shaking, no
blurriness, warm-up time around 20 sec., no dimness, no strange sounds,
nothing. It was perfectly fine.

All of a sudden last week I turned it on one day and after about 10
minutes the screen went black. There was no change in the picture before
this happened. At the same time the picture went black the green light on
the power button also went out. It didn't change to amber, or start
blinking. I did hear a relay click out, as is normal when you shut it
off.

About 3 or 4 seconds after going black, it seemed to go into its initial
power-on startup sequence again. The degaussing relay kicked in, I heard
the static hum, then the other realy clicked, the green light on the power
button came on, the degaussing relay dropped out and it seemed to be
warming up again. But instead of completing the startup sequence, after
about 5 seconds the green light went out again and I heard the relay click
out again. This cycle then repeats itself over and over. At power-on, 3
relay clicks and the light comes on, then after a few seconds the green
light goes out simultaneously with a relay click. Lather, rinse, repeat.

If left off for an hour or so it will power on normally and display its
usual crisp, clear picture. There are absolutely no defects in the
picture. Brightness, contrast, changing screen resolutions on the PC
(800x600, 1024x768, 640x480) all work normally and the picture is fine.
But after it warms up, *click* and the light goes out and the
startup-shutdown cycle starts again.

I unplugged the video cable from the PC to see how the power-on self-test
would go and it came up normally with the "No Video Signal" message and
the color bars, so that test passed.

I'm trying to decide what to do.

There are some *lethal* areas inside a monitor, especially the mains side
reservoir capacitor, and some *painful* areas, like the CRT anode and focus
supplies, which may result in severe involuntary muscle contractions causing
serious injury or further electroction.

If you are competent to go inside with the power on-

Arm yourself with a can of freeze spray and a hair dryer/heat gun with a
small nozzle. From cold, power up the monitor and see if carefully heating
any section of the circuitry narrows the fault down. When it shuts down, try
cooling each component in the area and try powering back on until you find a
thermally defective semiconductor or capacitor.

Failing that, personally I wouldn't recommend spending money on repairing a
7 year old 17" monitor, it just isn't worth it IMO.

Dave
 
S

Sam Goldwasser

Jan 1, 1970
0
Dave D said:
There are some *lethal* areas inside a monitor, especially the mains side
reservoir capacitor, and some *painful* areas, like the CRT anode and focus
supplies, which may result in severe involuntary muscle contractions causing
serious injury or further electroction.

If you are competent to go inside with the power on-

Arm yourself with a can of freeze spray and a hair dryer/heat gun with a
small nozzle. From cold, power up the monitor and see if carefully heating
any section of the circuitry narrows the fault down. When it shuts down, try
cooling each component in the area and try powering back on until you find a
thermally defective semiconductor or capacitor.

Failing that, personally I wouldn't recommend spending money on repairing a
7 year old 17" monitor, it just isn't worth it IMO.

I'm using exactly that monitor now. It's a great monitor.

Given your symptoms, I'd first suspect a bad connection in the AC input or
power supplies, or just a loose power cord. In my experience, these are
very reliable monitors. The only problem I've seen among three of them was
a dried up capacitor in the vertical output which resulted in only half a
picture.

Do follow the safety advice though!!!

--- 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 above is
ignored unless my full name is included in the subject line. Or, you can
contact me via the Feedback Form in the FAQs.
 
Ignore this poster. It's a troll.


Van said:
I've got a Dell Ultrascan 1000HS Model D1025TM that was manufactured in
May of 1998. It's quite similar to the Sony CPD-200GS (17" Trinitron
tube) without the audio. I'm the original owner and have had no
problems with it for 7 years until last week. The picture was fine, no
shaking, no blurriness, warm-up time around 20 sec., no dimness, no
strange sounds, nothing. It was perfectly fine.

All of a sudden last week I turned it on one day and after about 10
minutes the screen went black. There was no change in the picture
before this happened. At the same time the picture went black the green
light on the power button also went out. It didn't change to amber, or
start blinking. I did hear a relay click out, as is normal when you
shut it off.

About 3 or 4 seconds after going black, it seemed to go into its initial
power-on startup sequence again. The degaussing relay kicked in, I
heard the static hum, then the other realy clicked, the green light on
the power button came on, the degaussing relay dropped out and it seemed
to be warming up again. But instead of completing the startup sequence,
after about 5 seconds the green light went out again and I heard the
relay click out again. This cycle then repeats itself over and over.
At power-on, 3 relay clicks and the light comes on, then after a few
seconds the green light goes out simultaneously with a relay click.
Lather, rinse, repeat.

If left off for an hour or so it will power on normally and display its
usual crisp, clear picture. There are absolutely no defects in the
picture. Brightness, contrast, changing screen resolutions on the PC
(800x600, 1024x768, 640x480) all work normally and the picture is fine.
But after it warms up, *click* and the light goes out and the
startup-shutdown cycle starts again.

I unplugged the video cable from the PC to see how the power-on
self-test would go and it came up normally with the "No Video Signal"
message and the color bars, so that test passed.

I'm trying to decide what to do. In a past life I've done a little
soldering on a TV set or two (15 years ago) and I have the service
manual for it. Does the problem sound familiar to anybody? If it was
something like a cold solder joint I could probably remove the boards
safely and inspect them. Or, I could take it to a repair shop where I'm
guessing a repair might run around $100 or so. Or I could order a
refurb unit (same model) from a place I found online for $100 shipped
with a 90-day warranty. Or I could buy a closeout (but still new)
Viewsonic PF77 for $125 shipped.

I'm not ready to make the leap into an LCD panel yet. Good ones are
still relatively expensive, and there's no such thing as an all-purpose
LCD panel. The LCD that does everything I need it to do hasn't been
built yet for under $600.

I know in my head the new Viewsonic is probably the way to go, but in my
heart I hate to throw the Ultrascan out, especially since it appears, at
least to me, like the problem might be very easy to fix. As I said, the
picture is still bright, clear, and rock solid when it's on. I would
appreciate any advice or tips from those who know more about these
things than I do. I can't keep staring at this _really_ old and blurry
MultiSync 3D for much longer. My eyes are bad enough.

Thanks in advance,
VCS
 
V

Van Chocstraw

Jan 1, 1970
0
Sam said:
I'm using exactly that monitor now. It's a great monitor.

Given your symptoms, I'd first suspect a bad connection in the AC input or
power supplies, or just a loose power cord. In my experience, these are
very reliable monitors. The only problem I've seen among three of them was
a dried up capacitor in the vertical output which resulted in only half a
picture.

Do follow the safety advice though!!!

Thanks for both of your replies.

I have a healthy respect for high voltage and current. I adhere to the
hands-in-the-pockets rule until I'm sure all dangerous charges have been
neutralized. I have one of those big-resistor-welded-to-a-screwdriver
thingies that's been in my toolbox for ages.

I'll try another power cord first. The one in there isn't loose but it
couldn't hurt to try another one. I'll proceed from there. I would
just hate to throw it out. I'll poke around a bit (carefully) for a
while. It'll be a distraction from the mind-numbing array of choices
I'm wrestling with as far as a replacement goes. I'll let you know how
I make out. Thanks again.

VCS
 
T

Tom MacIntyre

Jan 1, 1970
0
Ignore this poster. It's a troll.

Do you realize that you are giving amateurish advice to the founder of
this group? :)

Tom
 
V

Van Chocstraw

Jan 1, 1970
0
Sam Goldwasser wrote:
I'm using exactly that monitor now. It's a great monitor.

Given your symptoms, I'd first suspect a bad connection in the AC input or
power supplies, or just a loose power cord. In my experience, these are
very reliable monitors. The only problem I've seen among three of them was
a dried up capacitor in the vertical output which resulted in only half a
picture.

Do follow the safety advice though!!!

--- 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

Sam, I see you are the author of the FAQ. You are to be commended for a
fine bit of work. I managed to get the main board out safely and am
starting to examine things more closely.

I have a comment regarding the Sony service manual for the CPD-200GS.
On page 2-2 it recommends shorting the anode and the anode cap to
chassis ground or aquadag AFTER removing the anode cap! What's more
there's a diagram that indicates one should NOT slide a screwdriver
under the rubber cap.

Sony's been making CRTs for a long time so it seems strange they would
recommend a dangerous procedure like that. Any cracks or pinholes in
the rubber and you could wind up getting quite a jolt.

VCS
 
S

Sam Goldwasser

Jan 1, 1970
0
I have a comment regarding the Sony service manual for the CPD-200GS.
On page 2-2 it recommends shorting the anode and the anode cap to
chassis ground or aquadag AFTER removing the anode cap! What's more
there's a diagram that indicates one should NOT slide a screwdriver
under the rubber cap.

Sony's been making CRTs for a long time so it seems strange they would
recommend a dangerous procedure like that. Any cracks or pinholes in
the rubber and you could wind up getting quite a jolt.

It does seem strange.

Perhaps they were worried about scratching the CRT? The glass is relatively
thin in that area.....

--- 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

Important: Anything sent to the email address in the message header above is
ignored unless my full name is included in the subject line. Or, you can
contact me via the Feedback Form in the FAQs.
 
V

Van Chocstraw

Jan 1, 1970
0
Sam Goldwasser wrote
<snip
I'm using exactly that monitor now. It's a great monitor

Given your symptoms, I'd first suspect a bad connection in the A input o
power supplies, or just a loose power cord. In my experience, thes ar
very reliable monitors. The only problem I've seen among three o them wa
a dried up capacitor in the vertical output which resulted in onl half
picture

Do follow the safety advice though!!

--- 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.ht
| Mirror Sites: http://repairfaq.ece.drexel.edu/REPAIR/F_mirror.htm
Sam, I see you are the author of the FAQ. You are to be commended fo
a
fine bit of work. I managed to get the main board out safely and am
starting to examine things more closely

I have a comment regarding the Sony service manual for the CPD-200GS.
On page 2-2 it recommends shorting the anode and the anode cap to
chassis ground or aquadag AFTER removing the anode cap! What's more
there's a diagram that indicates one should NOT slide a screwdriver
under the rubber cap

Sony's been making CRTs for a long time so it seems strange they woul

recommend a dangerous procedure like that. Any cracks or pinholes in
the rubber and you could wind up getting quite a jolt

VC
 
S

Sam Goldwasser

Jan 1, 1970
0
I have a comment regarding the Sony service manual for the CPD-200GS.
On page 2-2 it recommends shorting the anode and the anode cap to
chassis ground or aquadag AFTER removing the anode cap! What's more
there's a diagram that indicates one should NOT slide a screwdriver
under the rubber cap.

Sony's been making CRTs for a long time so it seems strange they would
recommend a dangerous procedure like that. Any cracks or pinholes in
the rubber and you could wind up getting quite a jolt.
It does seem strange.

Perhaps they were worried about scratching the CRT? The glass is
relatively
thin in that area.....

--- 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

Important: Anything sent to the email address in the message header
above is
ignored unless my full name is included in the subject line. Or, you
can
contact me via the Feedback Form in the FAQs.
 
Q

quietguy

Jan 1, 1970
0
Van said:
What's more
there's a diagram that indicates one should NOT slide a screwdriver
under the rubber cap.

That makes sense from a OHS perspective due to the risk of scratching the tube -
BUT like (I presume) most other guys I always did just that carefully anyway. And
I don't know of any techs that would grab the rubber with their hands - if there
are any they are much braver souls than me.

David
 
D

Dave D

Jan 1, 1970
0
Sam Goldwasser said:
It does seem strange.

Perhaps they were worried about scratching the CRT? The glass is
relatively
thin in that area.....

Perhaps it's a throwback to the old Trinitron tubes which IIRC had a special
anode cap with concentric contacts. They had a special tool to slide under
the rubber and release the 'catch', though it could be done with a little
care and a screwdriver.

Dave
 
V

Van Chocstraw

Jan 1, 1970
0
Dave said:
Perhaps it's a throwback to the old Trinitron tubes which IIRC had a special
anode cap with concentric contacts. They had a special tool to slide under
the rubber and release the 'catch', though it could be done with a little
care and a screwdriver.

Dave

Could be a throwback, although this model has a standard clip. Both the
Dell and the Sony manuals recommend the same thing. I used the
screwdriver method with a resistor. No problems. The anode cap had a
schmear of silicon-like grease underneath surrounding the contact
receptacle.

The biggest problem so far has been dirt. There are things in there
that look like they have hair growing on them. Ugh. It cleans up nice
though.
 
Top