N3JIM Power Supply
N3JIM's 10-amp power supply
Last updated Sat, 28 May 2011
KI6HDR (one of my buddies from electronics classes) gave me an old ICOM dual-band radio c. Oct 2010. Cool! The only problem--I needed a 10-amp power supply. I went out to Fry's and found a 12 volt, 150 watt switching power supply for about $60.
I put some spade lugs on a grounded appliance cord to get power in, then covered the terminal screws with some electrical tape. I put some Power Pole connectors on some 16 AWG wire and spade lugs on the other end, and I was on the air! But this quick-and-dirty job bothered me:
- The line in (120 volt) connections were all but exposed.
- No fuse.
- No on/off switch.
- The ventilated enclosure was kind of ugly, especially the terminal strip.
I went to Metro Electronics and bought an 8" x 6" x 3" project box, 12-volt 60 mm computer fan, and one of those computer power connectors with a built-in fuse holder and switch. (I like these a lot, because I've got tons of extra computer cords, I don't have to worry about strain relief, and the power cable isn't permanently sticking out of the box, getting worn out, etc.)
For ventilation, I cut a 60 mm hole for the fan (for exhaust) and a slot across the front of the box (for intake). This was the most difficult part of the entire project. Some other minor metalwork on the case (for the Power Pole output, power/fuse/switch, and an indicator light) got me to final assembly.
The switching power supply has a voltage adjustment, so I set the output for 13.2 volts. At 150 watts, this gives me about 11 amps output, (not 12A as mis-labeled here). Complete April/May 2011.
Full-size pictures (and more notes) are posted in this Flickr album.