Narrative:

Contacted hagerstown ground. Stated ready to taxi. Ground asked if I could make an intersection takeoff on runway 27 downwind, winds 060 /7. I stated I could. I then switched to tower on 120.3 and asked if cleared to takeoff. The frequency was clear of any xmissions. I remember thinking about getting back in time to watch a media event. The frequency was still quiet. Believing that the ground had cleared me for takeoff, I lined up on the runway. I still heard nothing on the radio, then took off. About 500' AGL, I saw commuter small transport cross my path about 1 mi ahead and 500' higher. I radioed tower that I had the traffic in sight--no reply. It was then that I checked the frequency on the digital radio and found that I was off on 120.5. You see, the radio's led readout was not making the numbers out completely. Well, as soon as I discovered this it told the tower I had the traffic in sight. The small transport plane responded with 'that's a nice violation.' then tower asked for my full north# and destination, and if I knew what I just did. I replied that I was off frequency. Tower then told me I took off west/O a clearance. My inexperience in not identing the radio problem on the ground and being at a strange field asking me to do a different departure than what I was expecting, and the fact that the aircraft had only one radio, in poor condition, all were contributing factors.

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Original NASA ASRS Text

Title: GA SMT UNAUTH TKOF. PLT WAS OFF FREQ WHEN CALLING THE TWR.

Narrative: CONTACTED HAGERSTOWN GND. STATED READY TO TAXI. GND ASKED IF I COULD MAKE AN INTXN TKOF ON RWY 27 DOWNWIND, WINDS 060 /7. I STATED I COULD. I THEN SWITCHED TO TWR ON 120.3 AND ASKED IF CLRED TO TKOF. THE FREQ WAS CLR OF ANY XMISSIONS. I REMEMBER THINKING ABOUT GETTING BACK IN TIME TO WATCH A MEDIA EVENT. THE FREQ WAS STILL QUIET. BELIEVING THAT THE GND HAD CLRED ME FOR TKOF, I LINED UP ON THE RWY. I STILL HEARD NOTHING ON THE RADIO, THEN TOOK OFF. ABOUT 500' AGL, I SAW COMMUTER SMT CROSS MY PATH ABOUT 1 MI AHEAD AND 500' HIGHER. I RADIOED TWR THAT I HAD THE TFC IN SIGHT--NO REPLY. IT WAS THEN THAT I CHKED THE FREQ ON THE DIGITAL RADIO AND FOUND THAT I WAS OFF ON 120.5. YOU SEE, THE RADIO'S LED READOUT WAS NOT MAKING THE NUMBERS OUT COMPLETELY. WELL, AS SOON AS I DISCOVERED THIS IT TOLD THE TWR I HAD THE TFC IN SIGHT. THE SMT PLANE RESPONDED WITH 'THAT'S A NICE VIOLATION.' THEN TWR ASKED FOR MY FULL N# AND DEST, AND IF I KNEW WHAT I JUST DID. I REPLIED THAT I WAS OFF FREQ. TWR THEN TOLD ME I TOOK OFF W/O A CLRNC. MY INEXPERIENCE IN NOT IDENTING THE RADIO PROB ON THE GND AND BEING AT A STRANGE FIELD ASKING ME TO DO A DIFFERENT DEP THAN WHAT I WAS EXPECTING, AND THE FACT THAT THE ACFT HAD ONLY ONE RADIO, IN POOR CONDITION, ALL WERE CONTRIBUTING FACTORS.

Data retrieved from NASA's ASRS site as of August 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.