Dell Trinitron 17" flaky - worth repairing?

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

Reply to
Van Chocstraw
Loading thread data ...

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

Reply to
Dave D

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:

formatting link
Repair | Main Table of Contents:
formatting link

+Lasers | Sam's Laser FAQ:
formatting link
| Mirror Sites:
formatting link

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.

Reply to
Sam Goldwasser

Ignore this poster. It's a troll.

Van Chocstraw wrote:

Reply to
9lnilnli080wdrd

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

Reply to
Van Chocstraw

Ignore this poster. It's a troll.

Van Chocstraw wrote:

Reply to
9lnilnli080wdrd

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

Tom

Reply to
Tom MacIntyre

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

Reply to
Van Chocstraw

Ignore this poster. It's a troll.

Van Chocstraw wrote:

Reply to
9lnilnli080wdrd

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:

formatting link
Repair | Main Table of Contents:
formatting link

+Lasers | Sam's Laser FAQ:
formatting link
| Mirror Sites:
formatting link

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.

Reply to
Sam Goldwasser

input or

are

them was

half a

formatting link

formatting link

formatting link

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

Reply to
Van Chocstraw

Ignore this poster. It's a troll.

Van Chocstraw wrote:

input or

are

them was

half a

formatting link

formatting link

formatting link

for a

CPD-200GS.

would

in

Reply to
9lnilnli080wdrd

CPD-200GS.

would

in

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:

formatting link
Repair | Main Table of Contents:
formatting link

+Lasers | Sam's Laser FAQ:
formatting link
| Mirror Sites:
formatting link

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.

Reply to
Sam Goldwasser

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

Reply to
quietguy

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

Reply to
Dave D

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.

Reply to
Van Chocstraw

Ignore this poster. It's a troll.

Van Chocstraw wrote:

Reply to
9lnilnli080wdrd

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.