EEVblog #365 - ESR Meter Bad Cap Monitor Repair

[Slobodan]

What is the purpose of those parallel solder lines on the ground plane?

[EEVblog]

What is the purpose of those parallel solder lines on the ground plane?

To lower the trace resistance. I have done several videos on this.

Dave.

[midasgossye]

How expensive are ESR meters and are there specs you have to watch out for?

[Slobodan]

What is the purpose of those parallel solder lines on the ground plane?

To lower the trace resistance. I have done several videos on this.

Dave.

Ah, yes. I have seen those videos, but I don't understand why they don't just "flood" the whole ground plane with solder instead of making those parallel lines.

[firewalker]

EEVblog #365 !!! "One year" of EEVblog videos.

Alexander.

[notsob]

"later model" bob parker design ESR meter link
http://www.anatekcorp.com/blueesr.htm

and the older model
http://clientes.netvisao.pt/greenpal/evb1.htm

[tom66]

Ugh - Samwha. Samwha caps are in no way to be considered good. They had a consistent 1-2 year manufacturing defect with their WB, WL and  MK series capacitors. This killed loads of Samsung and LG TVs. They are still dying - just a couple of months ago I picked up a 40" Samsung LCD TV with three bulging Samwha.

[SeanB]

Just stripped a 1997 made Samsung 24' CRT monitor - died from LOPT failure after 15 years of use. Uses a lot of Samwha caps inside, they are all still good, or at least are not bulging.

[SteveyG]

LG stands for Lucky Goldstar. 'Life's Good' is their slogan. Get it right! 

[tom66]

Just stripped a 1997 made Samsung 24' CRT monitor - died from LOPT failure after 15 years of use. Uses a lot of Samwha caps inside, they are all still good, or at least are not bulging.

I think it's mostly their newer ones - beforehand they were owned by Samsung then got spun off - maybe lost some key talent or just a consistent manufacturing defect.

[DL8RI]

Hi Dave,

I saw your videos on repairing these Monitors and I have done this several times... and I've a little question...
This tool you use to crack the clips open... how is it called? (seems to be some chisel for medical use?!)

I was always fighting with those stupid cases not to ruin the clips and the plastic-case itself. This tool seems to be quite handy (more than a knife, screwdriver, whatever ).

73 and thanks,
Martin

[miceuz]

I'm just wondering - you are measuring ESR of caps in circuit, caps frequently are in parallel together - it should affect ESR readings somehow, shouldn't it?

[nitro2k01]

Ah, yes. I have seen those videos, but I don't understand why they don't just "flood" the whole ground plane with solder instead of making those parallel lines.

My guess is that it is because you want a segment of solder to solidify roughly simultaneously over the whole segment when wave soldering. If you have a big solid area of exposed copper, one end might soldify while the other end is still being sprayed with solder.

[madires]

I'm just wondering - you are measuring ESR of caps in circuit, caps frequently are in parallel together - it should affect ESR readings somehow, shouldn't it?

Like resistors in parallel.

[mariush]

Yes, that's an important thing that wasn't mentioned at all in the video and it's important.

If capacitors are in parallel, when testing a capacitor the ESR value reported will be much lower, it can fool you into thinking a capacitor is still "good enough" to leave it there, and a few weeks later your monitor is broken again.

I'm otherwise really disappointed.

Dave, considering so many people watch your videos, and you know they're gonna recommend them to others, it's really not a good idea to keep using crap no-name capacitors and excuse yourself saying that's all you have. Also, considering a few capacitors in that area have failed, there's really no excuse for leaving those other capacitors on the board, even though they still measured good, you can never know how long they're going to remain good.  A name brand capacitor is half a dollar, even less, no reason to be cheap with that.

You should be more responsible about this, you're just encouraging people to make poor quality fixes.

[KD0CAC John]

The tool looked to me like a butter knife with the end cut off and I would think a bevel ground on end ?

[ModemHead]

... This tool you use to crack the clips open... how is it called? (seems to be some chisel for medical use?!) ...

It's a "spudger."  Commonly included in laptop and iPad, iPod repair toolkits.  Very cheap on eBay.

[madires]

I saw your videos on repairing these Monitors and I have done this several times... and I've a little question...
This tool you use to crack the clips open... how is it called? (seems to be some chisel for medical use?!)

AFAIK, it's called spudge tool or spudger.

I was always fighting with those stupid cases not to ruin the clips and the plastic-case itself. This tool seems to be quite handy (more than a knife, screwdriver, whatever ).

I'm using spatulas (width of 2-3 cm) from the DIY shop. They distribute the torque quite nicely across the width without damaging the case too much.

[Slobodan]

Ah, yes. I have seen those videos, but I don't understand why they don't just "flood" the whole ground plane with solder instead of making those parallel lines.

My guess is that it is because you want a segment of solder to solidify roughly simultaneously over the whole segment when wave soldering. If you have a big solid area of exposed copper, one end might soldify while the other end is still being sprayed with solder.

Thanks.

[DL8RI]

Hi!

a "Spudger", never heared of... would have never found it... thanks

Just ordered two via eBay... will be tested on the next "broken" TFT after my bench is usable again.

73,
Martin

[Slobodan]

About the spudger, is this one OK?

http://www.ebay.com/itm/Metal-Spudger-Scraper-Knife-for-Ipod-touch-4-Iphone-4-Ipad-2-Repair-Open-Tool-/330744063490?pt=Other_Tablet_eReader_Accessories&hash=item4d01e1e602

Or should I buy some other one?


And about caps, are Fujicon (TN and TM series) any good?

[Wytnucls]

Wikipedia says it is possible to measure ESR with a square wave generator and oscilloscope. Does anybody know how?
http://en.wikipedia.org/wiki/ESR_meter

[Monkeh]

About the spudger, is this one OK?

http://www.ebay.com/itm/Metal-Spudger-Scraper-Knife-for-Ipod-touch-4-Iphone-4-Ipad-2-Repair-Open-Tool-/330744063490?pt=Other_Tablet_eReader_Accessories&hash=item4d01e1e602

I've literally just got one of those. It seems fairly sturdy.

[ModemHead]

About the spudger, is this one OK? ...

Looks just like the one I have. It came in a kit with various other plastic implements of destruction. The only one of which I've found useful is the "black stick".  Really.  Just search "black stick spudger" on eBay.

[tom66]

Dave, considering so many people watch your videos, and you know they're gonna recommend them to others, it's really not a good idea to keep using crap no-name capacitors and excuse yourself saying that's all you have. Also, considering a few capacitors in that area have failed, there's really no excuse for leaving those other capacitors on the board, even though they still measured good, you can never know how long they're going to remain good.  A name brand capacitor is half a dollar, even less, no reason to be cheap with that.

You should be more responsible about this, you're just encouraging people to make poor quality fixes.

This is a very good point. A lot of people re-cap things with capacitors from RadioShack or Fry's or Maplins. About a month to a year or so later, the device dies - and they wonder why. A lot of it ends up in the trash, and is harder to repair because those caps were "close enough", but not the same.