Samsung 226BW

[PCBONEZ]

Re: Samsung 226BW

I have observed that cap locations are marked on the top deck with a circle, half black, half not, that seem to correspond with pos/neg leads on the caps.

Occasionally the silk screens have errors they don't fix.
One or some are marked backwards.
I take a snapshot from above, print it, and mark polarity and sizes right on it before I pull any caps.
It's just a good idea 'cause: 'shit happens'.
.
.
I clip the leads after soldering unless I'm having trouble getting the leads in the holes in which case I'll shorten them some.
You still want some excess lead to clip after soldering so you know you got a good bond.
Can't tell that if the lead is shorter than the solder.
.
.
Most people bend the leads a little to hold the caps in place for soldering. That works fine.
Just be gentle in the bending so you don't damage the rubber bung where the lead enters the cap.
.
Personally [at least for larger caps] I like to block them up under the board kind'a like blocking up a car. I have a collection of wood blocks, bottle caps, lids, small boxes, big nuts/washers, and so forth I use. For me I can get them in straighter that way. Won't win any soldering speed competitions with that method though... LOL.
.

[RATTLERMAN]

Re: Samsung 226BW

mockingbird

I bought these:

Panasonic FM 25v 820uF 10X25mm
United Chemi-Con KZE 25v 330uF 8X15mm
Rubycon RX30 50v 47uF 8X11.5mm
Panasonic FC 50v 2.2uF 5X11mm
Nichicon PM 50v 22uF 6.3X11mm

Will they work?
Thanks for your help!

Thanks PCBONEZ!

Any more soldering tips will be much appreciated.
Yes, I am an amateur!

I checked the polarity in my photos.
The sharpie marks and the silver stripes all align with the stenciled neg side.

Why are some of the components blobbed with the white goo?

thanks again!

[PCBONEZ]

Re: Samsung 226BW

Why are some of the components blobbed with the white goo?

At the factory they do that to hold things in place until they are soldered in.
One person places the components in the holes and glues them down.
Next person [or machine] solders them a bit later.
Production is limited by the amount of soldering equipment [& solder'ers] they have.
Don't want those people [solder'ers] spending their time placing components when you can do that with relatively unskilled people and some tubes of glue.
Also many factories use some form of auto-soldering machine so the whole works gets soldered at once. You can't have parts falling out in the machines.
.
Sometimes it's also done just to keep things from touching something else.
In PC PSUs there are often blobs to keep exposed coils from touching the heatsink or nearby caps.
.
If it's excessive sometimes it's not a bad idea to get rid of it when you can do so without damaging anything.
It doesn't exactly let parts dissipate their heat well.
I've seen transistors completely encased in it. - Not good...
.
.
Your cap choices look fine.
.

[mockingbird]

Re: Samsung 226BW

Panasonic FM 25v 820uF 10X25mm = 0.018
United Chemi-Con KZE 25v 330uF 8X15mm = 0.056

These are the caps I warned about that constitute the pi filter. I'm pretty sure you would get better results with the ESR of these caps matched a bit better, but if PCBONEZ says you're fine, you're probably fine.

I don't see any 25V 680uF caps in your list. Did you forget these two?

[RATTLERMAN]

Re: Samsung 226BW

uh-oh...
Lead spacing!

2 of the caps I purchased have different specs for lead spacing than the ones on the board.

Rubycon RX30 50v 47uF 8X11.5mm
The cap from my board is 6.5mm with 2.5 lead spacing, the rubycon is 3.5 L.S.

United Chemi-Con KZE 25v 330uF 8X15mm
My cap is 10mm with 5mm L.S. the new one has 3.5 L.S.

The other ones seem to be a match.
oh well!

[RATTLERMAN]

Re: Samsung 226BW

mockingbird
I don't see those caps on my board.
Is it possible that they used 25v 820's instead?
I have 5 of those.

[PCBONEZ]

Re: Samsung 226BW

Panasonic FM 25v 820uF 10X25mm = 0.018
United Chemi-Con KZE 25v 330uF 8X15mm = 0.056

These are the caps I warned about that constitute the pi filter. I'm pretty sure you would get better results with the ESR of these caps matched a bit better, but if PCBONEZ says you're fine, you're probably fine.

I don't see any 25V 680uF caps in your list. Did you forget these two?

You might be right but in this case he's changing caps on both sides of the coils about equally so I don't think it will be a problem.
.
Some day I'm going to have to set up the o'scope and take a PSU and change PI filter cap configurations all day to see how much it really matters.
I'd need quite a variety of same uF caps with different ESRs to generate enough meaningful data to really say anything for sure.
Were it not for that, I would have already done it.
.

[PCBONEZ]

Re: Samsung 226BW

mockingbird
I don't see those caps on my board.
Is it possible that they used 25v 820's instead?
I have 5 of those.

Yes.
Possible variation in production runs or board revisions.
Not super unusual, just confusing.
.

[RATTLERMAN]

Re: Samsung 226BW

My board is different than the one in this thread:
https://www.badcaps.net/forum/showthread.php?t=7900

Maybe that is a different model, the "SyncMaster"

You can see all of the cap locations and numbers on this picture of my board:

[mockingbird]

Re: Samsung 226BW

You might be right but in this case he's changing caps on both sides of the coils about equally so I don't think it will be a problem.

Am I mistaken in thinking that capacitors 3, 4, 5 and 6 are part of the pi filter? This is what I was basing my assumption on. I had the other revision of the board, so I had space to use 12.5mm caps. I used 12.5mm UCC LXY caps, which were OK, because the LXZ you referenced was the 25mm version. The SamYoung LXZ was 20mm. It's in the spec sheet. I used an FM for the 330uF and the ESR was only off by 0.007 IIRC.

I don't see those caps on my board.

You're right. My board is exactly like the one from th eother thread. Yours is a little different.

2 of the caps I purchased have different specs for lead spacing than the ones on the board

Easy. Make a horizontal bend with needlenose pliers at the very top of the leads near the bung (Don't put any pulling pressure on the leads or it may compromise the bung seal if the protrude out a little bit), and then make a vertical bend. You can tweak it til you have the correct lead spacing. Make the bends as tight as possible. The more lead you have, the more it will affect the impedence.

Some day I'm going to have to set up the o'scope and take a PSU and change PI filter cap configurations all day to see how much it really matters.

I actually mentioned in another thread that I mismatched the ESR by this coil in a repair, and it only lasted a few months. I think it blew the starter cap if that makes any sense. That's why I revised it with the LXY/FM combination:
UCC LXY 25V 820uF 12.5 x 20 = 0.046 1340
Panasonic FM25V 330uF 8 x 15 = 0.041 1240

He cannot use 12.5mm LXY, it won't fit like it did with my revision.

[PCBONEZ]

Re: Samsung 226BW

Am I mistaken in thinking that capacitors 3, 4, 5 and 6 are part of the pi filter? This is what I was basing my assumption on.

Presumably but I only see one coil with the 4 caps so if they are all in a PI then it's probably a 2C-1L-2C configuration.
.
You did what I would have done BTW.
Personally I don't like to stray that far from original specs but he already ordered caps and judging by what gets done in other similar 'screen threads' it will probably work fine.
At the very least it will work well enough to see if the unit has other problems.
.
The other caps don't appear to be in PI filters.
.

[RATTLERMAN]

Re: Samsung 226BW

Ack...it's so much stuff...I am an amateur!

(@ PCBONEZ, I love sushi, and I'm a cook.)

I could have bought these from the Capking website, but the ZLK series is not on the "good" list:
http://thecapking.com/25zlk820.html

I have plenty of time/patience, and a few more dollars to buy other caps if you think it is a good idea.

Why bother soldering if the cap is doubtful?
What caps would you put into this project?

Thanks again for your time!

James

[PCBONEZ]

Re: Samsung 226BW

Ack...it's so much stuff...I am an amateur!

(@ PCBONEZ, I love sushi, and I'm a cook.)

I could have bought these from the Capking website, but the ZLK series is not on the "good" list:
http://thecapking.com/25zlk820.html

I have plenty of time/patience, and a few more dollars to buy other caps if you think it is a good idea.

Why bother soldering if the cap is doubtful?
What caps would you put into this project?

Thanks again for your time!

James

The good list vs bad list thing is kind of a farce. [And here the sticky is never updated.]
In general caps from the UK, USA and Japan are reliable and consistent but anything else is hit-miss or miss-miss.
The reason is primarily natural impurities in Chinese Aluminum which aren't present in the aluminum used in UK, USA and Japan made caps.

'Good brand' Exceptions:

The Jap brand TK is known to be unreliable.
They are associated with OST so my assumption is they get Aluminum foil from their larger partner OST who uses Chinese AL.

Chemicon KZV, KZJ, KZG, TMV & TMZ series are unreliable.
Seems to be an issue with their electrolyte formula.
Only KZJ and KZG are common. The others are rather rare.
None of them are made any more but stocks aren't depleted everywhere yet.

Nichicon HN and HM made between 2001 and 2004 were overfilled.
Presumably an error in their written procedure for those two series.

Some Samxon [not Jap] have proven reliable, namely RS, GA, GC, GD series.
Other Samxon are either untested [because they aren't used often enough to say] or known bad.

~~~
Anything else is considered bad.
'Bad' really means 'unpredictable' and not that every run of caps is bad.

~~~
The current primary 'good brands' for low ESR -Lytic- caps are:
Nichicon, Chemicon, Rubycon, Panasonic, Sanyo [now Suncon], Samxon, Illinois Capacitor, NIC Components and Elna.
Except as mentioned above those are good.
There are other good brands but they don't offer much in the way of low ESR.

~~~
I probably would have used something like LXZ, FC, PW, maybe KY but I'm saying that without checking data sheets.
Is a little too close to nappy time here... LOL

I think what you already have ordered will work out fine.
If what you ordered was all I had on-hand I'd probably try them before ordering different caps.
If they don't work out, can always order different caps later.
.

[RATTLERMAN]

Re: Samsung 226BW

The new caps arrived today, and I installed them.
That was fun, but I think I need new glasses.

Hooked everything up, and I still have "2 seconds to black."

Oh well, at least I got some soldering experience...

[PCBONEZ]

Re: Samsung 226BW

I use the 3x lil 'ole lady reading glasses from the dollar store when I solder.
I get the small lens ones and perch on the end of my snoz so I can look through or over them as needed.

It's time to get a DMM if you don't have one.
Check the voltages at the OP connector.
Ideally they are written on the board.
.

[RATTLERMAN]

Re: Samsung 226BW

Will this serve the purpose?
It's old...from my motorcycling days.



New caps:

[PCBONEZ]

Re: Samsung 226BW

If it does AC and DC volts and resistance in the needed ranges that should be fine.
Won't need AC too much. In most cases a 200v range is enough.
For DC 20v is probably enough. More is better obviously.
Most meters do the full ohms range.

Beckman is a respected brand BTW. Not a junk brand.
If you haven't used it for a while a new battery might be a good idea.
.
.
You did clip the leads before testing the board, right?
.

[RATTLERMAN]

Re: Samsung 226BW

PCBONEZ
Yes, I clipped the leads.
Not easy, since my pointy wire cutter is a little gap-toothed on the pointy end.
I had to search out my cable cutter pair, with a better edge.

Also, I decided to re-do one connection, a little too close for comfort visually.
I think I got it right, but next time I will select the bend direction more carefully, and leave the leads more vertical.



Here are the spec sheet numbers on the Beckman:



I could buy a DMM, if necessary, I have an Amazon gift certificate burning a hole in my pocket.

Thank you !

[EGuevarae]

Re: Samsung 226BW

Just to be sure...
Screen DOES lite up and then goes off....?
My main question would be, do you note any noise between the On and then OFF , like a hiss, or a red/pink hue in the screen?

[RATTLERMAN]

Re: Samsung 226BW

EGuevarae

Thank you for reading!
My screen does the same things as it did before I replaced all the caps as described in this thread.

When connected to [power] and a video source, I see blue surround light at power button in the bezel, and all online images on the LCD, EVERYTHING, for about 2 seconds, and then it goes black.

I can also hit the [MENU] button and see the MENU for a brief time, but this does not repeat.
I am not sure if I do that before replacing the caps.

I see the [analog/digital] display upper left for a few seconds, then black.
This also does not repeat, unless I power down, and up again.

Thanks again!