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Help: need some help from an electrician or such.

Don't touch it any more than you already have. Thoose "small" things can easily fry your fingernails through rubber gloves. Don't play with anything else than 12v WITHOUT capacitors or you'll regret it in the end. Buy a new screen. You can get a brand new 22" monitor for about 175bucks (1500kr) so why fiddle in high voltage electronics.

Edit: not to mind that if you fiddle in it you shouldn't really connect it to your computer since if it burns anything in there (or your house) you've probably voided any warranty that you have for that as well.
 
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Legion said:
i dunno who it was hehe :p



well i kind of know why and what is the problem. I googled my symptoms on it and they said it's the power board or the power invertern that is broken, exactly what a power invertor is i'm not sure of as i cant seem to find a proper translation for it. And it was a lightningstrike that semifried the monitor, but it's only on the power circuitboard the error is on. And every other capacitator is completely flat except these two that are just beside each other. this is what it looks like but not just as much as this one http://soft.vub.ac.be/soft/_media/members/denniswagelaar/personal/dsc04926.jpg

http://www.seb.me.uk/static/dell-transistor-broken.jpg
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I have done quite a lot of soldering (...and blown quite some stuff and fuses and got fried a couple of times with up to 30kV ), there is simply now way to tell, if a buckled capacitor is really in need for changing, unless you measure it.
Also, the capacitors are not the weakest link but the ICs and transistor are. Could be that you have a microfracture on the PCB that closes when the board gets warm.
Could be, that a transistor from the power converter takes a timeout.
Could even be I get laid tomorrow...
This is not like analyzing what could be wrong with a computer installation, where a diagnosis is already pretty tough and only a assumption. In this case here there is absolutely no way to find the error, one can not even make a halfway decent assumption.
And any "repair" attempt is bound to fail, because you need to have the proper equipment. One can not simply solder with a clunky soldering iron near SMD parts, you need to have one which can be regulated and especially for that task, which would probably costs more than a new LCD.
Also even if you where lucky and it would function afterwards, there is absolutely no guarantee that you burn down your house with that repair afterwards, because you only fixed one error but not all.
If you had some experience, you would not ask here, so please leave your hands off it.
An amateur could maybe repair a 30 year old radio today, but surely not some high tech parts which today get replaced, because they simply are not repairable.
 
Im not so worried about you getting shocked taking it apart Im more worried about what happens when you put it back together.
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and just remember the ol' electricians magical loot theory - if you can microwave it, maybe it'll start working again... just overheat it enough... When you do finally put the transistors in the microwave, please record it with a webcam and put it on youtube... just kidding. Do go to a repair place to have it looked at by a pro.
 
JDaddy said:
Xenophage speaks the truth... if you don't know what you're doing inside a CRT, get the f&*k outta there. :wise:
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"Don't touch the inside of the CRT or ya might be CRiTted? :scratch2:
 
WoenK said:
Also, the capacitors are not the weakest link but the ICs and transistor are. Could be that you have a microfracture on the PCB that closes when the board gets warm.
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Electrolytic capacitors are the weakest link. However if they have blown there is a very good chance they will take out some IC's and/or transistors in the related circuitry when they go bad.

I know it is not a CRT but I will agree with all here that you don't want to mess with them if you don't know what you are doing.

In your LCD you are unlikely to face the same danger (assuming it is not a full wall size screen lol ). Take the advice above (and google for more) about discharging the capacitors and have a go at changing them.

I would not give this advice to everyone but you seem to be doing your research so good luck.

ps: unplug the monitor first :laugh:
 
xentric said:
Electrolytic capacitors are the weakest link. However if they have blown there is a very good chance they will take out some IC's and/or transistors in the related circuitry when they go bad.
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Sorry, but from his description there are not blown but only a bit buckled and it could be, that they have been that way for quite a long time.
And since his problems where after a lightning strike there could be absolutely anything damaged. Capacitors do not fry from electro static charges as fast as ICs do and can take quite some power spikes also.
giving him even the smallest hope, that he could fix it is liefethreatening reckless. This is not like changing a light bulb.
 
xentric said:
Electrolytic capacitors are the weakest link. However if they have blown there is a very good chance they will take out some IC's and/or transistors in the related circuitry when they go bad.

I know it is not a CRT but I will agree with all here that you don't want to mess with them if you don't know what you are doing.

In your LCD you are unlikely to face the same danger (assuming it is not a full wall size screen lol ). Take the advice above (and google for more) about discharging the capacitors and have a go at changing them.

I would not give this advice to everyone but you seem to be doing your research so good luck.

ps: unplug the monitor first :laugh:
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as for them being the weak link, yes they are as every google or youtube i get which have the same symptom everyone says it's those and they look like everyone says aswell.

And yep been googling and youtubeing a bit on discharging :) I will look for a friend who has the knowledge to do it though, or see if i can find a small firm that can do it cheap. I wont go to the service place cause daamn they cost a lot aparantly lol.
And i think the cap's very pretty low ones (yes i know they can still be dangerous) like 15v or such.
And yes I UNDERSTAND i should not fiddle with it, i think you guys made that pretty clear :p
 
you can replace the caps its not that hard at all, read the values on the side find the same ones on eBay. you can use a cap rated for a higher voltage with out problems. the capacitance can be the seam or higher if the circuit is used for storage, or a filter, ect, if you don't know its use keep the other value the same. they are also polarized take a note when you pull the old ones if the silk screening dose not show a circle with half of it colored in over one pin, colored in side is negative.

identify caps:
badcaps.net/pages.php?vid=5

Find replacements:
ebay.ca
ca.digikey.com/scripts/dksearch/dksus.dll?Cat=131081

Learn to desolder/solder:
http://www.aaroncake.net/electronics/desolder.htm
http://www.instructables.com/id/How-to-solder/

any other questions just ask google
 
...I think it is really just a matter of time until some pseudo-experts give tips where to look up on the net the "How to do an Appendectomywith kitchen tools" and how easy it is...
Dudes, there are some things that are not advisable!
 
WoenK said:
Sorry, but from his description there are not blown but only a bit buckled and it could be, that they have been that way for quite a long time.
And since his problems where after a lightning strike there could be absolutely anything damaged. Capacitors do not fry from electro static charges as fast as ICs do and can take quite some power spikes also.
giving him even the smallest hope, that he could fix it is liefethreatening reckless. This is not like changing a light bulb.
Click to expand...

You are correct that semiconductors are more susceptible to damage from a lightening strike or even static as far as that goes however electrolytic caps are far more likely to just die on their own and bulging is a very good and almost certain symptom of failure.

I can't see this as life threatening if he has done the proper research and to me it appears he has. In fact more so than some who have posted here (not meaning you because I mostly agree with what you have posted).

Read up and read again. Good luck and be safe.

Crossing the road can be dangerous these days.
 
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I'm not really that good at interpreting this but according to:

(ElsäkFS 1996:2):

Arbete som får utföras av annan än elinstallatör:

4. Utförande, ändring eller reparation av anläggning som ingår i skyddsklenspänningskrets med nominell
spänning högst 50 V, effekt högst 200 VA och ström begränsad av säkring högst 10A eller annat
överströmsskydd med motsvarande skyddsverkan, dock inte inom utrymmen med explosiv miljö.

(Google translate for non swedes)

Work to be performed by other than the installers:

4.Construction, alteration or repair of the plant as part of the safety extra low voltage circuit with a nominal
voltage 50 V, 200 VA maximum power and power limited by a maximum 10A fuse or other
overcurrent protection with similar protective effects, but not in areas with explosive atmospheres.


And the fact that it is a 220V appliance might even make it illegal for you to touch those components yourself. So don't burn down your house with it or you might be in serious trouble.
 
You guys kill legion yet?
 
Legion said:
As i said in an earlier thread my monitor has gone funky. it works once it warms up but it's taking longer and longer for it to warm up. So since i dont have any warranty left on it i opened it up and had done some googling on what faulty capacitors etc look like. I noticed that 2 things that look like this https://www.elfa.se/elfa3~se_sv/elfa/init.do?shop=ELFA_SE-SV#item=67-193-22; was a tiny tiny bit raised on their top but if i look at the other ones they are completely flat. Are these two most likely the faulty ones as the monitor does work once it warms up or is there likely something more faulty with it?

Also how hard would it be to remove them and replace them for a noob :p
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I'll be happy to speak to you about your issue..25years as an electronic tech..only on teamspeak tho.. PM me if you want some help (for TS info) :)
 
No I seriously meant kill.

Some of the advise I see in here leaves me wondering how many liable suits will occur when he dies or sets fire to his house.
 
Agreeing with everyone who said it's not worth the risk to life and limb.

I used to work at a production facility where some of the brilliant workers would make bombs out of capacitors and go out behind the building and blow crap up. Charged cap and a throw switch on a timer.... BOOM. I'll never touch one after seeing the damage they managed to do.
 
Calin said:
I used to work at a production facility where some of the brilliant workers would make bombs out of capacitors and go out behind the building and blow crap up. Charged cap and a throw switch on a timer.... BOOM. I'll never touch one after seeing the damage they managed to do.
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There are the Darwin Awards for these people. :laugh:
 
xentric said:
You are correct that semiconductors are more susceptible to damage from a lightening strike or even static as far as that goes however electrolytic caps are far more likely to just die on their own and bulging is a very good and almost certain symptom of failure.

I can't see this as life threatening if he has done the proper research and to me it appears he has. In fact more so than some who have posted here (not meaning you because I mostly agree with what you have posted).

Read up and read again. Good luck and be safe.

Crossing the road can be dangerous these days.
Click to expand...
If he knew what he was doing, he would not ask here in first place. Asking here means he probably never even used a soldering iron and looking up the solutions in the net means, he is not even an amateur.
And one wrong soldering spot can become quite life threatening. I blew a few fuses because I "fixed" my CRT and all the sudden had 120V on my computer chassis. Was lucky that the fuse worked the way it should and that I had some low Amperes on the chassis (and both the computer and monitor worked fine until I accidently touched the chassis).
Other time I was lucky, that my "fixed" PSU started burning while I was in front of the computer and not taking a long bath, would have burned down the whole house including me.

There are simply some advices that are absolutely wrong to hand out.
 
RadlinLastway said:
I'm not really that good at interpreting this but according to:

(ElsäkFS 1996:2):

Arbete som får utföras av annan än elinstallatör:

4. Utförande, ändring eller reparation av anläggning som ingår i skyddsklenspänningskrets med nominell
spänning högst 50 V, effekt högst 200 VA och ström begränsad av säkring högst 10A eller annat
överströmsskydd med motsvarande skyddsverkan, dock inte inom utrymmen med explosiv miljö.

(Google translate for non swedes)

Work to be performed by other than the installers:

4.Construction, alteration or repair of the plant as part of the safety extra low voltage circuit with a nominal
voltage 50 V, 200 VA maximum power and power limited by a maximum 10A fuse or other
overcurrent protection with similar protective effects, but not in areas with explosive atmospheres.


And the fact that it is a 220V appliance might even make it illegal for you to touch those components yourself. So don't burn down your house with it or you might be in serious trouble.
Click to expand...

to my knowledge and according to the text that is for installations, ie installing laundrymachines and such.

WoenK said:
If he knew what he was doing, he would not ask here in first place. Asking here means he probably never even used a soldering iron and looking up the solutions in the net means, he is not even an amateur.
And one wrong soldering spot can become quite life threatening. I blew a few fuses because I "fixed" my CRT and all the sudden had 120V on my computer chassis. Was lucky that the fuse worked the way it should and that I had some low Amperes on the chassis (and both the computer and monitor worked fine until I accidently touched the chassis).
Other time I was lucky, that my "fixed" PSU started burning while I was in front of the computer and not taking a long bath, would have burned down the whole house including me.

There are simply some advices that are absolutely wrong to hand out.
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i have use a soldering iron :p and i do have some knowledge from school and such but it was a long time ago :p
 
If this is a LCD monitor and the power supply is external to the monitor, and the caps you found are inside the monitor, then go ahead and give it a go.

Swollen caps have indeed failed. You may find some crusty material in the vicinity, this would be the electrolyte from inside the cap that has boiled off.

Practice your soldering skills on a project or two before working on a circuit board though. Solder isn't "glue", and technique is everything. Solder bridges can be a pain in the ass.

Yes, you degreed people (MA in medieval studies? LOL)... academically, there can be potentially lethal voltages present. However, if the wall current isn't going into the actual monitor (many designs are like this now, keeps the manufacturer from having to go through safety certs with different models), the chances of contacting lethal voltage in a manner that can actually be lethal or even harmful is pretty remote.

A 4700 microfarad cap with a working voltage rating of 25v (if Legion was meticulous and matched the cap he's actually seeing in the provided link. He strikes me as being that detail oriented.) is gonna be hard pressed to stop the kid's heart unless he opens up his chest cavity and appplies the leads directly to cardiac muscle. Think he can stay conscious long enough to do that if he's cracking open his own chest?




AG
 
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Legion said:
i have use a soldering iron :p and i do have some knowledge from school and such but it was a long time ago :p
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Even though some might -rep me for it...

Don't do it, I still want to read your theory when it is finally finished in a few years :D
Seriously...there are way too many things that could go wrong and fry you and others.
This is not something one can fix over the net or phone.
Anybody saying that it is possible is a reckless dumbarse that will, after you won the the Darwin Award, laugh his ass off.
 
Calin said:
Agreeing with everyone who said it's not worth the risk to life and limb.

I used to work at a production facility where some of the brilliant workers would make bombs out of capacitors and go out behind the building and blow crap up. Charged cap and a throw switch on a timer.... BOOM. I'll never touch one after seeing the damage they managed to do.
Click to expand...


I remember when I was installing car audio in Edmonton I would take a few small caps out of broken headunits add short leads to them tuck a few under the bench next to to power bar wrap the leads to the prongs on my work lamp turn the bar off plug it in crawl under the dash and yell out my lamp is not working. one of my co workers would see the bar is off, turn it on for me and POP scare the fucking hell out of them. :D almost as much fun as a balloon full of oxygen and acetylene you poke with a hot brazing rod no big fire ball but loud as space shuttle on launch.
 
Legion said:
well that part i knew :)
that they can store power for some time and such. but the thing is the qualified tech would cost me as much as a new monitor (1500 -2kish peds) while replacing those two myself would cost like 20 ped xD



thanks for the info, i knew about the +- stuff though so will If i do this take note of that :)
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i would like inform you that in RL ped are don t accepted :p
 
Aeris_is_back said:
I remember when I was installing car audio in Edmonton I would take a few small caps out of broken headunits add short leads to them tuck a few under the bench next to to power bar wrap the leads to the prongs on my work lamp turn the bar off plug it in crawl under the dash and yell out my lamp is not working. one of my co workers would see the bar is off, turn it on for me and POP scare the fucking hell out of them. :D almost as much fun as a balloon full of oxygen and acetylene you poke with a hot brazing rod no big fire ball but loud as space shuttle on launch.
Click to expand...

How many branches does your family tree have left? one? two?
 
Trina Xenophage said:
How many branches does your family tree have left? one? two?
Click to expand...

How many benches have you called your workplace? Pranks like that are pretty typical in an electronics shop. :)
 
We used to do that all the time. Especially with "noobs" right out of school. Good training too. Teaches folks to THINK before they just grab stuff. Never went too far to be dangerous, just enough to get a chuckle from the older folk and educate the newbies.

Most learned pretty quickly. Some, however, were destined for a rough career in electronics.

We had a circuit trainer we taught IC's on way back in the day. It had switchable power from DC to AC. OMG, after harping on one of our trainees over and over to ALWAYS check the voltage, we left it switched to AC/120. OMG, 5V and 12V DC ic's make a fountain of fire at AC/120!!!!!!!
 
Trina Xenophage said:
Ambulance ride 2k dollars.
Salary for professional to restart your heart 50k dollars..
Surgery to amputate mangled hand 35k dollars..
Physical therapy for a few years to retrain for normal life..75k Dollars
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Dont worry,he lives in scandinavia.Medical expenses are covered:)
 
Who is gonna teach him Thevinin and Norton Theory so he can check the repair and make sure what caused the issue in the first place does not still exist? Or worse yet caused more problems like a nicely toasted or shorted resister to mess around with currents a bit.

Oh wait you guys were just gonna let him solder away like a high school project and then apply power on the assumption all is well.

Was someone at least gonna let him borrow a scope to see if the repair is within specs so he dont burn his house down IF he lives thru power up on the chance something else went wrong?

Award tender!!!! ID like a round of Darwin for EVERYONE please.
 
kinda silly so many of you are so paranoid of a old crt, you may get a small scare if you short a energized cap but the only thing that will really hurt you is the flyback transformer though If its not plugged in it cant hurt you.

so come on now lift your skirt find your balls, maybe check in your purse next to your tampons and replace a few caps =)
 
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