Narrative:

This was the departure from hell. A thorough preflight preceded takeoff. At about 800 ft, however, the ptt button started jittering, so that reception (and presumably transmission) was 'motorboating.' this caused extraordinary distraction as I was entering the clouds. First, it caused a delay in activating the transponder from 'standby.' second, the nature of the problem was not immediately known, so I was trying to fly the plane solo, in the soup at low altitude, and diagnose the problem. In a few mins, I unplugged the pilot ptt and headset, and grabbed the passenger's side set. This required reaching across the passenger side yoke to activate the ptt. And, just to make sure this was a flight from hell, navigation 1 failed. It had been checked out by an avionics shop immediately before flight, and I was assured all was well. At some point within 15 mins of this, I was given VFR on top, heading 210 degrees. Either I was so rattled from the equipment failures or from communications problems, but I remained at the last assigned altitude, 9000 ft, instead of climbing to a VFR altitude, 9500 ft. This came to light when I requested direct olm, as I was flying the last assigned heading (210 degrees). This got the controller's attention. I can find nothing in the rules which allows me to leave the last assigned heading without a 'resume own navigation' or other clearance. Perhaps one was issued, but not to my knowledge. The rest of the flight was uneventful. With regard to human factors, a lack of current experience contributed to this altitude deviation. My letting early mechanical troubles infect later phases of flight compounded this.

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Original NASA ASRS Text

Title: SMA DEPARTS IMC, HAS PTT PROBLEM RESULTING IN POOR TRANSMISSION. NAV 1 FAILS. ASSIGNED VFR ON TOP BUT REMAINED AT INST ALT.

Narrative: THIS WAS THE DEP FROM HELL. A THOROUGH PREFLT PRECEDED TKOF. AT ABOUT 800 FT, HOWEVER, THE PTT BUTTON STARTED JITTERING, SO THAT RECEPTION (AND PRESUMABLY XMISSION) WAS 'MOTORBOATING.' THIS CAUSED EXTRAORDINARY DISTR AS I WAS ENTERING THE CLOUDS. FIRST, IT CAUSED A DELAY IN ACTIVATING THE TRANSPONDER FROM 'STANDBY.' SECOND, THE NATURE OF THE PROBLEM WAS NOT IMMEDIATELY KNOWN, SO I WAS TRYING TO FLY THE PLANE SOLO, IN THE SOUP AT LOW ALT, AND DIAGNOSE THE PROBLEM. IN A FEW MINS, I UNPLUGGED THE PLT PTT AND HEADSET, AND GRABBED THE PAX'S SIDE SET. THIS REQUIRED REACHING ACROSS THE PAX SIDE YOKE TO ACTIVATE THE PTT. AND, JUST TO MAKE SURE THIS WAS A FLT FROM HELL, NAV 1 FAILED. IT HAD BEEN CHKED OUT BY AN AVIONICS SHOP IMMEDIATELY BEFORE FLT, AND I WAS ASSURED ALL WAS WELL. AT SOME POINT WITHIN 15 MINS OF THIS, I WAS GIVEN VFR ON TOP, HDG 210 DEGS. EITHER I WAS SO RATTLED FROM THE EQUIP FAILURES OR FROM COMS PROBLEMS, BUT I REMAINED AT THE LAST ASSIGNED ALT, 9000 FT, INSTEAD OF CLBING TO A VFR ALT, 9500 FT. THIS CAME TO LIGHT WHEN I REQUESTED DIRECT OLM, AS I WAS FLYING THE LAST ASSIGNED HDG (210 DEGS). THIS GOT THE CTLR'S ATTN. I CAN FIND NOTHING IN THE RULES WHICH ALLOWS ME TO LEAVE THE LAST ASSIGNED HDG WITHOUT A 'RESUME OWN NAV' OR OTHER CLRNC. PERHAPS ONE WAS ISSUED, BUT NOT TO MY KNOWLEDGE. THE REST OF THE FLT WAS UNEVENTFUL. WITH REGARD TO HUMAN FACTORS, A LACK OF CURRENT EXPERIENCE CONTRIBUTED TO THIS ALTDEV. MY LETTING EARLY MECHANICAL TROUBLES INFECT LATER PHASES OF FLT COMPOUNDED THIS.

Data retrieved from NASA's ASRS site as of July 2007 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.