Narrative:

Preparing to depart from runway 01; I had checked the AWOS and had reset my local airport unicom frequency and had monitored the frequency taxiing to the departure runway. After run-up; I announced my intentions to depart [runway] 01. At about 400 ft AGL and 3/4 way down the runway; I noted that there was a plane that had begun its takeoff run for runway 19. I called the aircraft on the advisory frequency with out response and switched to approach control. It was at this time that I noticed that the frequency that I had selected was XXX.025 rather than XXX.05. I will never make that mistake again!

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Original NASA ASRS Text

Title: A pilot taxied and departed Runway 1 using proper CTAF communications procedures but on the incorrect frequency and had a near miss with an aircraft landing on Runway 19.

Narrative: Preparing to depart from Runway 01; I had checked the AWOS and had reset my local airport UNICOM frequency and had monitored the frequency taxiing to the departure runway. After run-up; I announced my intentions to depart [Runway] 01. At about 400 FT AGL and 3/4 way down the runway; I noted that there was a plane that had begun its takeoff run for Runway 19. I called the aircraft on the advisory frequency with out response and switched to Approach Control. It was at this time that I noticed that the frequency that I had selected was XXX.025 rather than XXX.05. I will NEVER make that mistake again!

Data retrieved from NASA's ASRS site 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.