I had one blow up in a Fender Twin Reverb amp that I was getting going again for a guy who bought after it had sat unused for many years. I heard a hissing sound and then before I could flip the switch it exploded and blew foil and paper all over the shop! Nasty.
I always sort of figured that the old ones contained PCB's too.
I had one blow up in a Fender Twin Reverb amp that I was getting going again for a guy who bought after it had sat unused for many years. I heard a hissing sound and then before I could flip the switch it exploded and blew foil and paper all over the shop! Nasty.
I always sort of figured that the old ones contained PCB's too.
The problems with the premature failure of many "modern" electrolytics is well documented, and is basically due to manufacturing errors/defects and poor quality control.
Oh, no. The story is much better than that.
Taiwanese engineer gets a job, with intent to commit industrial espionage. gets his big chance. grabbed the file and photocopied all four pages.
didn't know about the fifth page. describing the stabilizing agent. straight out of Indiana Jones.
a bazillion caps were made using the deficient highly secret formula. they seem to have been made even after the purloined formula was found to be defective. _________________ Conventional wisdom among radio guys is that $1 spent on antennas is worth $10 spent on amplifiers. Solve RF problems with antennas to the greatest extent possible before increasing power.
Taiwanese engineer gets a job, with intent to commit industrial espionage. gets his big chance. grabbed the file and photocopied all four pages.
didn't know about the fifth page. describing the stabilizing agent. straight out of Indiana Jones.
a bazillion caps were made using the deficient highly secret formula. they seem to have been made even after the purloined formula was found to be defective.
Yup, that's the documented story I read several years ago when the motherboard problem with bad caps was rampant. _________________ 2x Asus RT-AC68U
Joined: 09 Feb 2010 Posts: 2 Location: Radom / Poland
Posted: Tue Feb 09, 2010 21:55 Post subject: Re: Router and Power Supply information - Bad Capacitors
redhawk0 wrote:
Bad capacitors...notice the domed tops...they should be perfectly flat.
one 16V@1000uF, and two 16V@470uF
My ones were completly flat, but the router's was working simillar to description (LEDS, firmvare restoration allwys completed, but during "Radio ON" it was, and stil is losing the connection via LAN and WiFi, with "Radio OFF" it worked fine but there was no WiFi). I exchanged the capacitors (but I putted 6,3V@1000uF as was oryginally) it helped a little bit, now it works for an hour with "Radio ON" and after that time starts to disconnect, connect ...
Does enyone knows the reason, should I exchange this 1000uF capacitor with 16V one, or there is something else.
Thanks in adwance.
PawKrz74
I have two 470uF/16V capacitor and one is 1000uF/6,3V. 1000uF capacitor is round at the top and I am going to change it, should I replace it with 16V capacitor.
Joined: 04 Jan 2007 Posts: 11564 Location: Wherever the wind blows- North America
Posted: Sun Mar 14, 2010 12:12 Post subject:
flei wrote:
Is there model that 1000uF capacitor is 16V?
I have two 470uF/16V capacitor and one is 1000uF/6,3V. 1000uF capacitor is round at the top and I am going to change it, should I replace it with 16V capacitor.
Should I maybe change 470uF capacitors also?
Yes....16V are fine....and yes...change all 3 caps.
Most likely your power supply also has a bad cap.
redhawk _________________ The only stupid question....is the unasked one.
Joined: 24 Feb 2009 Posts: 2026 Location: Sol System > Earth > USA > Arkansas
Posted: Sun Mar 14, 2010 16:20 Post subject:
An excellent place to purchase the "exact" specifications for your bad capacitors is at http://www.mouser.com. It would appear they also have an 'international' part of their company which covers many countries.
I have gotten my replacement caps from them multiple times. Usually talking cheap for what you pay and if you need to get large quantities, it gets a bit cheaper. _________________ E3000 22200M KongVPN K26
WRT600n v1.1 refirb mega 18767 BS K24 NEWD2 [not used]
WRT54G v2 16214 BS K24 [access point]
Try Dropbox for syncing files - get 2.5gb online for free by signing up.
Read! Peacock thread
*PLEASE* upgrade PAST v24SP1 or no support.
Joined: 24 Feb 2009 Posts: 2026 Location: Sol System > Earth > USA > Arkansas
Posted: Sun Mar 14, 2010 17:53 Post subject:
slybunda wrote:
i dont get it, am i the only person on here that replaces failed electrolyte caps with solid polymer ones?
What benefit would that do? In addition, what is the cost difference on changing to that type? _________________ E3000 22200M KongVPN K26
WRT600n v1.1 refirb mega 18767 BS K24 NEWD2 [not used]
WRT54G v2 16214 BS K24 [access point]
Try Dropbox for syncing files - get 2.5gb online for free by signing up.
Read! Peacock thread
*PLEASE* upgrade PAST v24SP1 or no support.
Joined: 04 Jan 2007 Posts: 11564 Location: Wherever the wind blows- North America
Posted: Sun Mar 14, 2010 18:07 Post subject:
Sure...Solid Polymer Caps are a good choice...but for the cost...probably not so much.
The real advantage is the SP Caps will take more heat and not break down like the standard electrolytic type.
In a Power supply...SP caps might be best (seeing it is an enclosed supply and temps get higher)...but in a router itself...probably not as cost effective.
You also have to remember that the SP caps are larger then the electrolytics...they can't pack the same capacitance into the small size package like those found in standard electrolytics.
redhawk _________________ The only stupid question....is the unasked one.
Taiwanese engineer gets a job, with intent to commit industrial espionage. gets his big chance. grabbed the file and photocopied all four pages.
didn't know about the fifth page. describing the stabilizing agent. straight out of Indiana Jones.
a bazillion caps were made using the deficient highly secret formula. they seem to have been made even after the purloined formula was found to be defective.
Yup, that's the documented story I read several years ago when the motherboard problem with bad caps was rampant.
Also, this is what caused Abit to go out of business due to all the lawsuits that were brought to them because of the bad caps _________________ Netgear 6400v2 running Toastman Tomato mod firmware
Great finding! I will physically inspect my Asus WL-500g Premium to look out for the same issue. It makes sense that unreliability will drop into a device if it has bad capacitors; I have seen it many times with personal computers but never on routers. Thank you for sharing this important information with all of us.
For the record:
Recently I fixed ASUS WL-500gP by exchanging one capacitor (AFAIR 16V@470uF) AND exchanging flauty power supply