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View Full Version : Help! 12V 5amp power supply - possible to repair?


Kurpal
May 30, 2009, 02:56 PM
The other day I was charging my batteries and my power supply let out a little "puff." I cracked open the power supply and discovered one of the capacitors was shot (blew out the top, the "puff" sound).

I went over to radio shack and picked up a 1000uf 35vdc capacitor to replace the 1000uf 10vdc capacitor that had blown. Initially I soldered it in reverse polarity and tested, no dice, I switched it to the correct way, still no luck. I also replaced one of the wire bridges as it had blown along with the rectifier. I am about to throw it in the trash but I thought I would post to see if anyone has another idea on how to fix it.

The second picture shows the new capacitor in place, reverse polarity. I don't know anything about capacitors and if they would be damaged being reversed. Also, I noted that a wire looked as if it bridged over a resistor and was cut or if it was also blown out like before. I just don't know why someone would put a wire bridging a resistor, why put the resistor in at all?

Weather is great and I would like to get flying, otherwise I would just wait the few weeks to get a new one.

rick.benjamin
May 30, 2009, 07:42 PM
That's the AC side of your power supply.
If one of those caps died, maybe the bridged rectifier died also.
Maybe a varistor also needs replacing.

Here's a couple or three choices I googled, may be better to replace the bad one.

http://www.allelectronics.com/make-a-store/item/PS-1252/12V-5A-POWER-SUPPLY-W/-CIG-LIGHTER-JACK/1.html
http://www.all-battery.com/browseproducts/110-240V-AC-to-12V-DC-5A-Switch-Power-Supply.html
http://www.toysonics.com/12v-dc-5a-110-240v-ac-power-supply.html