Narrative:

In cruise at 8500 ft a fairly large puff of smoke came out of my dash by the radio stack. There was a smell of burned rubber. It was quickly irritating to my throat and eyes. I immediately throttled back; set my mixture to rich. I then turned off all electronics and master power and alternator. As I was doing that I noticed comm 1 was dead. My main concern was the way it was affecting my breathing. After a little internal debate I powered back up one electronic at a time and contacted ATC and declared an emergency. ATC responded and guided me to a nearby airport. I landed without incident. The radio was immediately pulled and has been shipped off to be repaired.

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Original NASA ASRS Text

Title: PA28 pilot reported a puff of smoke from his radio stack while in cruise at 8500 FT. All electronics were turned off and the faulty radio identified. COMM 2 was used to declare an emergency and vectors received to the nearest airport.

Narrative: In cruise at 8500 FT a fairly large puff of smoke came out of my dash by the radio stack. There was a smell of burned rubber. It was quickly irritating to my throat and eyes. I immediately throttled back; set my mixture to rich. I then turned off all electronics and master power and alternator. As I was doing that I noticed COMM 1 was dead. My main concern was the way it was affecting my breathing. After a little internal debate I powered back up one electronic at a time and contacted ATC and declared an emergency. ATC responded and guided me to a nearby airport. I landed without incident. The radio was immediately pulled and has been shipped off to be repaired.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.