Samsung 2493HM fine vertical lines after cap replacement

[LogicalUser]

I've got a Samsung 2493HM that suddenly stopped working a week back. Nothing but a blinking blue light when powered.
Left it for 10min and it sprung to life, but only that one time, then back to blinking light

I found and replaced the one visibly bulged capacitor on the power board (CB853 2200uf 10v) and now the monitor turns on and seems to work, however there are some minor picture issues:

When certain shades of grey are displayed it shows what I'd describe as noise, sort of a constantly shifting 'fuzziness', almost like an extremely fine test pattern

I can see very faint tightly packed fine vertical lines throughout whiteish objects & windows (even more noticable in shadows & gradients)
Certain shades of grey also seem to have a slight pinkish hue to them
(same on two diff comps, using both HDMI & DVI inputs)

Any ideas on what the issue might be now?

Would my replacing just the one bulged cap cause this?
Some sort of issue reassembling the unit perhaps?

Edit: Turned it back on 20min later and the monitor was entirely normal for first 5min, but the 'noise' in greys then returned, followed by the vertical lines a minute or two later

[mariushm]

Re: Samsung 2493HM fine vertical lines after cap replacement

The remaining capacitors are in various degrees of quality - a capacitor doesn't fail instantly by becoming bulged. Some don't even bulge at all.

While they're not bulged you have no guarantee they still function within specifications.... normally you could check them by removing them from the board and measuring the capacity but that's just one important characteristic of capacitors - impedance (esr) is another characteristic.
However, this impedance can only be measured with a specialized equipment (esr meter) which costs 80-100$.

So often, it makes sense to spend 2-5$ and replace all capacitors instead of replacing just one capacitor.

[LogicalUser]

Re: Samsung 2493HM fine vertical lines after cap replacement

I'm still rather amateur at soldering, and while I've got some experience with mod chip installs this was my first attempt at replacing capacitors.

As such, replacing just the one rather isolated bulged cap seemed a far less daunting first step than replacing a dozen caps of various sizes next to other components, several glued down/to other components, etc...

The cap I used I got from a tech that did a free service call for Samsung to fix the caps on my 46" TV. He gave me a 2200uf 16v cap to replace the bulging 2200uf 10v Samwha WL series capacitor in my monitor.

[crazyjonny]

Re: Samsung 2493HM fine vertical lines after cap replacement

I also have a 2493hm that works after i leave it unplugged for a week or so then nothing but a black screen and the power light after i shut her down for the night. Im about ready to order the caps as i post this--will let you know how it goes.

[mariushm]

Re: Samsung 2493HM fine vertical lines after cap replacement

Well LogicalUser, if you open it up and:
1. (optional) post a clear picture of the boards inside
2. write here everything that says on the capacitors
3. mention where you live (country)

We can give you suggestions on what to buy. Replacing capacitors is really not that hard.

Same applies to you crazyjonny ... post clear pictures of insides and the markings on capacitors and location and we can give you advice on what to buy.

(don't assume one of you posts pictures - each of you may have different versions of the boards inside)

[LogicalUser]

Re: Samsung 2493HM fine vertical lines after cap replacement

My camera is not here ATM, however the power board is a BN44-00195A

All caps on power board are Samwha:
1x 450WV 82uf (Big one, no series listed)
1x 35v 470uf (RD series)
2x 35v 1000uf (RD series)
1x 10v 1000uf (RD series)
1x 10v 2200uf (WL series)
1x 50v 2.2uf (WL series)
1x 50v 22uf (WL series)
3x 50v 47uf (WL series)
2x 50v 10uf (WL series)

the other board is marked BN41-00962A, and has 19 solid capacitors of various sizes (no brand, black on top)

I'm located Canada

[mariushm]

Re: Samsung 2493HM fine vertical lines after cap replacement

Ok, I've kind of reverse engineered Samwha's site and saved the datasheets here:

ftp://helpedia.com/pub/temp/datashee...et%203/Samwha/

They have some horrible Flash with a button for the pdf download but the pdf themselves are somewhere else on their servers.

So basically, Miniature.pdf ...

RD starts at page 12 and they're "standard" series

1000uf 10v - 544 mA ripple
1000uf 35v - 974mA ripple
470uf 35v - 521mA ripple

Impedance is not specified but when selecting capacitors to replace these, you should try to get the ones with as low impedance as possible.

WL starts at page 23 and they're "Extremely Low Impedance" so you'll need to be particularly careful at picking low impedance capacitors to replace them

2200 uF 10v = 0.050 ohm impedance, 1400mA ripple.

A good store close to you is digikey.com - others are mouser.com , rs-components.com (http://www.alliedelec.com/), farnell.com - see what gives you smaller shipping fees and better prices.

Go to digikey.com, pick Aluminum Electrolytic capacitors, select the uF value you need, then select the voltage and one or two voltages above your voltage ... ex if your capacitors are 10v, pick 16v and 25v as well.
It's safe to install capacitors rated for higher voltage so you're just widening your options.
Run a search and sort by ripple value, then from the list you get, pick the capacitor that would fit in the area where the old capacitor is located and which has lower impedance than your old value.


Ex for 2200uF 10v WL series, which has 0.050 ohm impedance and 1400mA ripple and is 12.5mm wide, 20mm tall, then I could replace it with this:

http://search.digikey.com/us/en/prod...2357-ND/613718

2200uF 10v 12.5mm x 20mm 0.018 ohm, 2600mA

or

http://search.digikey.com/us/en/prod...402-ND/2433536
(same specs, just a series more resistant to heat)

or

http://search.digikey.com/us/en/prod...1510-ND/756026

2200uF 10v 12.5mm x 20mm 0.035 ohm, 1900mA

and if you think you can fit taller capacitors, the options explode...
same, if you may have 15-16mm in diameter where that capacitor is, you could select capacitors with even better specification. all that's important is:
* keep uF value
* keep v value or go slightly higher
* the impedance (esr) must be equal or lower than the old value (if unknown, try to get as low as possible)
* the ripple value must be equal or better than the original value
* pick something that would fit in the area of the old capacitor
* pay attention to the height

Ok, now repeat this search process for the other caps and post the links to each capacitor you choose and we'll give you feedback.

[LogicalUser]

Re: Samsung 2493HM fine vertical lines after cap replacement

If I'm understanding correctly, (slightly lower impedance, slightly higher ripple, same dimensions) then these should be good replacements for the WL series caps:

http://search.digikey.com/ca/en/prod...1751-ND/589492
http://search.digikey.com/ca/en/prod...1887-ND/589628
http://search.digikey.com/ca/en/prod...1603-ND/589344
http://search.digikey.com/ca/en/prod...1896-ND/589637
http://search.digikey.com/ca/en/prod...1890-ND/589631

[mariushm]

Re: Samsung 2493HM fine vertical lines after cap replacement

You're understanding correctly, but it's more like
- higher ripple almost never hurts, so the higher the better - though keep the capacitors the same type (polymer capacitors have super high ripple values but may not be suitable to replace regular electrolytic caps)
- impedance value should be slightly lower, a much, much lower value than the impedance of the original capacitors may cause problems. 0.018 vs 0.050 is not a big difference... 0.018 vs 0.150 would be a big difference.

So your first selection, Nichicon PW is OK specification wise, but you can do better - basically any one of the ones I linked in my previous post are better.

Note... the 2.2uF, 10uF, 22uF and 47uF are capacitors that don't have high ripple values or low impedances so what you picked for those looks OK to me.. They also are unlikely go bad, unless they're near something that heats a lot.

The big capacitor (in dimensions) is also unlikely to be bad, those fail rarely but it's not unheard of.
Focus on the larger uF capacitors.

[LogicalUser]

Re: Samsung 2493HM fine vertical lines after cap replacement

for the higher uF & RD caps:
http://search.digikey.com/us/en/prod...441-ND/2433575
http://search.digikey.com/us/en/prod...445-ND/2433579
http://search.digikey.com/us/en/prod...0225-ND/266235
http://search.digikey.com/us/en/prod...0230-ND/266240

The Nichion PW was surprisingly the only 2.2uF 50v listed with enough ripple

[mariushm]

Re: Samsung 2493HM fine vertical lines after cap replacement

Ok. For the 1000uF and 2200uF, you can probably do better.

Without seeing the board I can't tell for sure, but you can probably fit 25 mm high capacitors there because I'm sure a transformer or something else is higher than the capacitors.

1000uF, 35v what you chose is fine

470uf, this also works : http://search.digikey.com/us/en/prod...2415-ND/613776

1000uF,10v :
12.5mm wide: http://search.digikey.com/us/en/prod...2379-ND/613740
12.5mm wide http://search.digikey.com/us/en/prod...1681-ND/756197
10mm wide: http://search.digikey.com/us/en/prod...424-ND/2433558
10mm wide : http://search.digikey.com/us/en/prod...2366-ND/613727
All above rated for 25v and 16v, but as I said going up in voltage is not a problem, the rating is just the MAX the capacitor supports.

2200uf 10v:

25mm tall: http://search.digikey.com/us/en/prod...2369-ND/613730
25mm tall: http://search.digikey.com/us/en/prod...1667-ND/756183
20mm tall: http://search.digikey.com/us/en/prod...2357-ND/613718
25mm tall: http://search.digikey.com/us/en/prod...1837-ND/589578

Anyway, you now have an ideea about what works and what doesn't.
See how much shipping costs on digikey - you may be surprised to see it's 30$, that's how much it is to ship here to Romania where I live - it may be less since you're in Canada. You go hunting for these brands and series on the other sites I mentioned, if the shipping costs are too much on digikey.

Now that I think about it, a part of these I probably have in my box of capacitors as I ordered a lot in the past months, so if you don't find anything convenient I could probably mail you some for about 5$ in shipping and the digikey price. But as I'm in Romania, it would take more than a week to reach you.

[retiredcaps]

Re: Samsung 2493HM fine vertical lines after cap replacement

See how much shipping costs on digikey - you may be surprised to see it's 30$, that's how much it is to ship here to Romania where I live - it may be less since you're in Canada

Digikey and mouser are both $8 USD to Canada for shipping and handling.

[LogicalUser]

Re: Samsung 2493HM fine vertical lines after cap replacement

Just so I'm clear, the 2180mA ripple is a better choice than the 1790mA ripple cap when replacing an original cap @ 521mA ripple? Can one go too high?

Is there a reason beyond cost that this board features both very low impedance/high ripple caps and more standard caps?

As for height, yes, there is a heatsink that's aprox 25mm tall, and the 2200uF 16v cap I installed just barely fit

[crazyjonny]

Re: Samsung 2493HM fine vertical lines after cap replacement

1000uf 35v 399-6120-nd
470uf 35v p5554-nd
1000uf 10v p12353-nd
82uf 450v p10154-nd
2200uf 10v p12357-nd
22uf 50v p13461-nd
2.2uf 50v p13462-nd
47uf 50v p13464-nd
10uf 50v p13478-nd

this was what i ordered from digi-key last night around 11 dollars
my board is--bn44-00195a

[LogicalUser]

Re: Samsung 2493HM fine vertical lines after cap replacement

Getting back to this now that I'm less busy. Planning on ordering the following:


http://search.digikey.com/ca/en/prod...1887-ND/589628
http://search.digikey.com/ca/en/prod...1603-ND/589344
http://search.digikey.com/ca/en/prod...1896-ND/589637
http://search.digikey.com/ca/en/prod...1890-ND/589631
to replace
1x 50v 2.2uf (WL series)
1x 50v 22uf (WL series)
3x 50v 47uf (WL series)
2x 50v 10uf (WL series)

http://search.digikey.com/us/en/prod...441-ND/2433575
http://search.digikey.com/us/en/prod...445-ND/2433579
http://search.digikey.com/us/en/prod...0225-ND/266235
http://search.digikey.com/us/en/prod...0230-ND/266240
for:
1x 35v 470uf (RD series)
2x 35v 1000uf (RD series)
1x 10v 1000uf (RD series)
1x 10v 2200uf (WL series)

[LogicalUser]

Re: Samsung 2493HM fine vertical lines after cap replacement

Kinda forgot about this monitor sitting in the corner, never got around to ordering the fresh caps.

Looking at it again, it seems one of the caps is out of stock, but this seems a suitable replacement http://www.digikey.ca/scripts/DKSear...51700819405183

I also realized I missed the big cap.
The markings on the cap (Samwha 450WV 82uf, HE 105*C) do not correspond to any of Samwha's cap series, so I don't really reference point in terms of ripple or ESR, beyond someone's mention elsewhere that it should be a low ESR cap

none appear to match it's height exactly, but stepping up to 25mm height this http://www.digikey.ca/product-detail...1695-ND/483292 is the lowest ESR cap rated @ 105C