Troubleshooting computer monitors without power

I have two computer monitors that I want to fix, but unfortunately I am not allowed to work on them or test them at all while there is power in it. I am allowed to observe, and that's it. I was wondering if anyone could give me any ideas on how to fix them without power?

The first one is a Samsung Syncmaster 750s that is warped. Each colour is warped a different amount, in an effect that looks like the opposite of pin-cushioning. I can't see any obvious fried things.

The second is a Hyundai 1772E that doesn't appear to be getting power to the picture tube. (I can't make sure, because I'm not allowed to test it.) I don't know if the tube is supposed to warm up visibly or anything, but I see no change in it. The standby light turns on, so it is not a completely blown power supply.

So if anyone can suggest anything for these, which doesn't involve touching it with the power on, that would be great. Also, if anyone has any service manuals or schematics for either of these, I would be very grateful.

Thanks Andrew Howard

Reply to
Andrew Howard
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there's Samsung 700-series on there

Reply to
Jules

First of all, to service these, you will need the proper service manuals, at least a discent DVM, and you WILL have to apply power to verify the voltage readings in order to determine the fault areas. As for tracing out signal paths, and etc, an oscilloscope will be necessary.

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Reply to
JANA

at

voltage

Why would they need service manuals? I've been fixing computer monitors for years, never had a service manual for one.

Reply to
James Sweet

Correct, except that in many cases an experienced technician won't require a manual, especially for a generic fault. In my opinion, having to troubleshoot these problems with no power applied is ridiculous. The IT approach to electronics troubleshooting?

Tom

Reply to
Tom MacIntyre

what do you mean "I am not allowed to work on them or test them at all while there is power in it"? if these are YOUR monitors, than you can do whatever you want. If these are NOT your monitors, then let the moron who made this ridiculour rule deal with it. You cannot fix a monitor with no power applied. can a mechanic fix a car without running the engine at all? maybe in some case, but most of the time then need to run the engine. What about a doctor analogy, how can you diagnose and cure a patient if you are not allowed to take blood pressure, heart rate, etc. You get the picture. You are nnot stupid. Whoever said that you can fix the monitors but yo cannot apply power is stupid.

BTW: I hope you know what you are doing, yes, it can be dangerous and maybe that why the "no-power-policy", buut still, if you know what you are doing, either apply power, or give up.

Reply to
chibitul

Some people won't fix a table lamp without the service manual. :)

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Reply to
Sam Goldwasser

Huh, I've never seen a service manual for a table lamp.... :-)

WT

Reply to
Wayne Tiffany

He may be a student and that is the rule he must follow If you can't be helpful STFU!

Reply to
rb

Had you thought that this might be a young fellow whose mum or dad is (quite rightly) worried about safety?

I certainly wouldn't encourage any young beginner to poke around in a monitor with power on

David

chibitul wrote:

Reply to
quietguy

I do about half my monitor repairs with the power off, it's pretty easy to find a shorted semi or bad capacitor that way, some faults there's just no way around the live testing though.

Reply to
James Sweet

He was being helpful.

Tom

Reply to
Tom MacIntyre

Nobody has the right to tell anybody STFU on this forum.

That same thought crossed my mind, just who is imposing this limitation. Realize this may be a child or ,,,,,,,,, who knows. I'm not saying it is but to be ignorant of the possibility is ,,,,,,,,ignorant.

Imagine being taken to a room with monitors, or anything which your job is to fix, but you must change the parts without powering them up and when you put then back together completely they must work.

I would burn the place down and not lose a wink over it, they are KILLING technical minds. There is way too much of that going on today. Needless to say, I would turn the job down. Wouldn't be the first time.

JURB

Reply to
ZZactly

It actually is a rule imposed by my parents, as suggested by someone else. I'm 19 and have been doing electronics for a while and am aware of the safety issues involved, but while I'm living at home, I respect the rules imposed on me by my parents. Even if I hate them (especially in this case). It took me long enough to convince them that I knew how discharge everything adequately to be able to even touch the thing with the power off. So I don't think I'll be able to work on the while they are live until I either leave home, or get a job in the industry for a while. So if anyone has any ideas about the monitors... ;)

Thanks Andrew Howard

Reply to
Andrew Howard

Tough luck son, but I applaud you for honoring your parents - that's more important.

WT

Reply to
Wayne Tiffany

Hi Andrew

My (sort of) sympathy - you are in a difficult situation, but you have done well by seeking advice here, and also by allowing your parents to feel safe.

However, since you are 19, and have had some experience, perhaps you could handle your parents concerns in a gentle manner that might also allow you to extend your skills

I do think though that unless you have a fair knowledge about monitors and how they work etc that the repair task may be difficult - especially so if you do not have a service manual.

As a suggestion, perhaps you could detail your intended method of testing the monitor on this group, also noting the safety/danger issues you are aware of etc. Then let your parents read your post and the feedback that many of the good guys here usually offer. Assuming your post(s) demonstrate awareness of the specific dangers involved, and the good guys validate your ideas, this might reassure your parents and convince them to allow you a little more freedom to explore the exciting and sometimes vicious world of powered on gear.

However, I would be interested to read what others on this group think of this idea

Cheers

David - who was lucky enough to have a retired radio tech as a mentor when he started building and fixing mains (240v) powered gear (at around age 10 or so). My tech friend was a good guy who never failed to give me dire warnings if my building and fixing wasn't up to scratch, safety wise.

David

Andrew Howard wrote:

Reply to
quietguy

I originally thought that it was imposed by an employer or university department, etc...as the father of two, I believe that you are correct to heed your parents.

In case it hasn't been suggested, check this out, and let your parents know that you are educating yourself in the safety issues.

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Good luck.

Tom

Reply to
Tom MacIntyre

quietguy wrote in news: snipped-for-privacy@REMOVE-TO-REPLYconfidential-counselling.com:

*snip*

Speaking of safety, would using a GFCI outlet provide an extended measure of safety over a normal outlet when working on a TV?

Puckdropper

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Reply to
Puckdropper

" snipped-for-privacy@aol.com" bravely wrote to "All" (12 Sep 05 23:54:07) --- on the heady topic of "Re: Troubleshooting computer monitors without power"

ZZ> From: snipped-for-privacy@aol.com ZZ> Xref: core-easynews sci.electronics.repair:342008

ZZ> Nobody has the right to tell anybody STFU on this forum.

ZZ> That same thought crossed my mind, just who is imposing this ZZ> limitation. Realize this may be a child or ,,,,,,,,, who knows. I'm ZZ> not saying it is but to be ignorant of the possibility is ZZ> ,,,,,,,,ignorant. ZZ> Imagine being taken to a room with monitors, or anything which your ZZ> job is to fix, but you must change the parts without powering them up ZZ> and when you put then back together completely they must work.

ZZ> I would burn the place down and not lose a wink over it, they are ZZ> KILLING technical minds. There is way too much of that going on ZZ> today. Needless to say, I would turn the job down. Wouldn't be the ZZ> first time. ZZ> JURB

Jerry, the limitation isn't wrong per se. I always have to unplug an appliance before changing any components. I may have tack soldered the occasional cap or resistor with the power on but only for test purposes. Seriously now, no one in his right mind would replace a HOT or psu chopper in a hot chassis. Going to take a chill pill... tada!

A*s*i*m*o*v

... Back when I was a boy, we sucked the air out of our own vacuum tubes!

Reply to
Asimov

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