I'd been hoping to use a battery system to avoid any 60 hertz buzz, but some setbacks prompted me to try using my trusty Max Burton 200 watt converter, which I pulled out of storage after a year of disuse.

The only "modifications" I did to the radio was to cut down the existing red and black DC power lines, and use a "Cigarette lighter" style plug, into which I placed the Cobra-provided 2 amp fuse.

Mostly, I just wanted to see if my equipment would work electronically... I rigged up a pair of 4 foot firestick antennas to serve as an impromptu vertical dipole, and ran some RG58 from the antenna to the connectors, then I plugged the new cigarette lighter plug into the port on the Converter, and ran the line from the converter back to a plug.

(Full disclosure: The coax and the power lines were run in parallel. Not ideal, but I was just going to see if it worked.)

I plugged in the converter, and turned it on. The converter's fan began a familiar whir, and a familiar red LED began to glow. The radio wasn't doing anything... oh, because it was off. I turned it on. The back-lit display began to glow, and soon, I was receiving static from channel 9.

I turned the volume back down a bit, and was about to adjust the gain when... *POP!*

Oh, that noise can't be good... but the radio display is still glowing, and I still hear static. The red LED and fan on the converter were still going strong... but there were tendrils of smoke coming out of the vent holes. *POP!*

I unplugged the device before I might experience another pop. The LED on the converter and the back-lit display on the radio faded to darkness. I felt the converter, and it was cold. I sniffed at the converter, and smelled... not burning plastic... more like fresh un-buttered popcorn. I took out the cigarette lighter, and checked the fuse. The fuse hadn't burnt out. I'd only had the setup running for a few seconds.

Any Ideas?

Cobra claims that any of their radios will work with a 12-15 volt power supply as long as it puts out at least 2 amps. Their 2 amp fuse seems to suggest that they never draw more than 2 amps.

In the past, I've used this exact 200 watt converter to power 12 volt appliances that draw 7-12 amps. Sometimes as much as 2 hours a week for two years straight. Never any problems... although the manual does warn not to leave the converter running when it isn't powering anything.

Is it possible that the 2 amp radio doesn't draw enough power, and this somehow causes trouble for the converter?

Would running "shielded" coax parallel to the power cord (all 46 inches of it) at almost 8 inches apart, and never using it to transmit in that time be a problem?

Could dust buildup in the converter have led to arcing?