Narrative:

Departed pwk with student. Proceeded to schaumburg for traffic patterns. Changed the #1 radio to unicom, did not realize I was transmitting on #2, pwk tower. Tower called schaumburg and I realized my mistake. In the future, I will brief all students on the possibility of this and verify the radio I am transmitting on so this embarrassing situation does not happen again. I did call tower and apologize.

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Original NASA ASRS Text

Title: SMA PLT INCORRECTLY TUNES FREQ BELIEVING IT 06C UNICOM WHEN ACTUALLY XMITTING ON PWK TWR FREQ.

Narrative: DEPARTED PWK WITH STUDENT. PROCEEDED TO SCHAUMBURG FOR TFC PATTERNS. CHANGED THE #1 RADIO TO UNICOM, DID NOT REALIZE I WAS XMITTING ON #2, PWK TWR. TWR CALLED SCHAUMBURG AND I REALIZED MY MISTAKE. IN THE FUTURE, I WILL BRIEF ALL STUDENTS ON THE POSSIBILITY OF THIS AND VERIFY THE RADIO I AM XMITTING ON SO THIS EMBARRASSING SIT DOES NOT HAPPEN AGAIN. I DID CALL TWR AND APOLOGIZE.

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.