"Blinking lights of death" ? Netgear Switch GS108

[Robin Laing]

David Liguori wrote:
> 
> 
> Aldo Foot wrote:
>> On Wed, Apr 29, 2009 at 7:23 PM, Robert L Cochran
>> <cochranb at speakeasy.net> wrote:

>>   
> One of the more common mechanisms for failure of electrolytic capacitors 
> is too high an ambient temperature over a period of time.  Usually the 
> temperature rating is on the cap.  You say the room is well-ventilated 
> but that doesn't rule out too high an ambient temperature in a room full 
> of equipment, especially if it was sitting on top of or in a rack full 
> of other equipment.  It's more likely to have open rather than short 
> circuited.  An ESR (effective series resistance) meter will tell.
> 
> If you're pretty sure the capacitor is what's ailing it and it's 
> through-hole rather than surface mounted, I would consider it well worth 
> fixing, or even trying if there's greater than a 10% success 
> probability.  Many 8-port switches aren't worth fixing below that.
> 

Another issue is using capacitors that are close to the operating 
voltage of the system.  12V and use 15V capacitors.  This doesn't give 
any overhead for voltage spikes or surges caused by charging and 
discharging circuits.

Remember that many circuit boards are multi-layer now so be careful if 
you are working with a thru-hole circuit board.

Have fun.
-- 
Robin Laing