The Bad Capacitor FAQ

[jacksonlyn]

Hello so I am a newbie but last Tuesday morning I went to turn my Toshiba LCD 55" on, the green LED power light came on and stayed on the screen blinked as if it was going to come on and blinked back out. I could still see the back light on but have no sound.I called Toshiba who talked me through the troubleshoot of unplugging the tv pressing and holding the power button on the tv for 20 seconds wait 2 minutes and then plug back in and press power button still tv would not come on; even after tech support had me repeat the above process 3 times. they informed me of a repair shop near me to take tv to; took the TV to the shop two days later and the tv came on without a problem even turned the tv off and on and unplugged 3 times at the shop by repairman who did not keep tv. now again yesterday morning tv played fine left house for 2 hours came back and turned tv on and the same problem started again. my tv is 3 years old and out of warranty. I actually thought due to heat and humidity was why tv started to act up. HELP... I NEED SOMEBODY...HELP

[selldoor]

THIS IS A STICKY - I Cant understand when you have the whole of the forum to post in you have posted here. Dont answer this here just start you own thread.

[Traum]

Hi, I'm new so be nice. I have a vizio model no:E420VSE SERA NO:LWJQMVBN2700392.NO POWER, LIGHTS OR SOUND.UNPLUGGED HELMUT POWERADE TONIGHT 30 SECONDS. NO CHANGE?

[davexnet]

Hello ,
the links in FAQ @ 7.1 are bad.
http://www.badcaps.net/forum/showpos...48&postcount=8

Have these tips been relocated?

[moni]

Polaroid FLX3711B capacitors details I need to know

[moni]

I need help about the capacitors details.
Polaroid FLX 3711B Monitor Repair Kit 13 Capacitors for MLT070AX Power Supply

[8ternity]

Report that all URL in 7.1 is not working anymore!

Originally Posted by willawake

7. [ How do I do the cap replacement? ]

7.1. Please read the following links :

Topcat's HowTo - Overview of Recapping
http://www.badcaps.net/tips/

Topcat's HowTo - Capacitor Removal
http://www.badcaps.net/tips/rem/

Topcat's HowTo - New Capacitor Installation
http://www.badcaps.net/tips/inst/

7.2. I want to learn good soldering, do you have any tutorials?

Yes, check the following links :

Elecraft Builder Resources (Click on Soldering Tutorial)
http://www.elecraft.com/Apps/K2info.html

Apogee Kits Downloads (Click on ApogeeKits Free Illustrated Guide to Electronics Soldering)
http://www.apogeekits.com/downloads.htm

The Basic Electronics Soldering & Desoldering Guide
http://www.epemag.wimborne.co.uk/solderfaq.htm

University of North Carolina - Soldering Techniques paper
(Click on soldering.pdf)
http://www.chem.unc.edu/undergrads/...m142l_wightman/

There is no easy way to teach soldering. It is like an art. You have to learn what is a good solder joint and then practice to achieve it. One of the tricks is to get the hole wetted with a tiny bit of solder before you start to feed solder down the hole. Watch closely what is happening to the solder while you are working and you will learn.

7.2. I think I can ignore all the advice given on this forum and repair my board the way I like, it’s gonna be ok right?

You might be lucky but probably you will trash the board. Badcaps members and moderators offer good guidance, please do not ignore their advice.

7.3 What values of caps should I use to replace the ones on the board?

You can either be safe and stick to the same values already on the board or you could use other values. You should be careful about decreasing the voltage, it is generally not recommended but it is ok to increase it. You can increase the capacitance (uf) as you see fit but the larger the voltage and the larger the capacitance, the wider and taller the capacitor. The larger cap may not fit in the place of the original cap. So if we give some examples :

1000uf 6.3V - You could replace with 1000uf 10V or 16V there is no problem.
330uf 25V - These are seen on some boards like Gigabyte. You can probably replace with 1000uf 16V like we did on a few boards without problems

Another consideration is cost. The larger the cap value, the more expensive it will be. No point to increase the cap values too much and pay more than necessary for a stable machine. The board will be perfectly stable using the same values of caps that were already on the board but this time using caps from a good manufacturer.

The safest thing to do is to keep to the same values as are already on the board. Use some 10V capacitors instead of 6.3V if you wish but trust that the board designers did know what they were doing when the designed the board.

7.4 There is a row of caps close together and I do not have small enough caps to fit the same number of caps there.

Generally a row of caps are connected in parallel so all the + leads of the caps are connected together and all the - leads of the caps are also connected together. You could for instance use half the number of caps but with double the value and only place the caps in every other capacitor position, leaving each position inbetween free. When you remove the caps however you must refill the holes of the positions you leave vacant with a little bit of solder to ensure that the circuit remains complete. When you remove the caps and dont clear the holes there is probably enough solder remaining there to complete the circuit but let's be sure and add a little solder to each hole while heating the solder pad of each hole.

Please note that it is not 100% certain that a row of caps is connected in parallel so this might not work in all cases.

[capmo]

I think its a lost cause but I would really appreciate if someone could update those links.
Would be a great reference.