Narrative:

While taxiing into position on runway 12R the first officer accomplished the confign check. This check requires moving his left hand very close to the #1 communication to push the test confign button. His hand brushed the frequency control knob on the right side of the #1 communication FLIP-flop control head changing the frequency from 119.9 to 119.825. While we thought we were on tower we were not. After sitting a couple mins in silence I looked down and discovered the error and reset. The tower said they had tried to call us 6 times. This is the second time this confign test has resulted in a change of frequency at a bad time. Other capts told me the same thing.

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Original NASA ASRS Text

Title: FK10 MOVING INTO POS FOR TKOF, FO COMPLETED BEFORE TKOF CHK HIT THE #1 COM FREQ CTL KNOB RESULTING IN BEING OFF TWR FREQ FOR ABOUT 2 MINS BEFORE THE ERROR WAS DISCOVERED.

Narrative: WHILE TAXIING INTO POS ON RWY 12R THE FO ACCOMPLISHED THE CONFIGN CHK. THIS CHK REQUIRES MOVING HIS L HAND VERY CLOSE TO THE #1 COM TO PUSH THE TEST CONFIGN BUTTON. HIS HAND BRUSHED THE FREQ CTL KNOB ON THE R SIDE OF THE #1 COM FLIP-FLOP CTL HEAD CHANGING THE FREQ FROM 119.9 TO 119.825. WHILE WE THOUGHT WE WERE ON TWR WE WERE NOT. AFTER SITTING A COUPLE MINS IN SILENCE I LOOKED DOWN AND DISCOVERED THE ERROR AND RESET. THE TWR SAID THEY HAD TRIED TO CALL US 6 TIMES. THIS IS THE SECOND TIME THIS CONFIGN TEST HAS RESULTED IN A CHANGE OF FREQ AT A BAD TIME. OTHER CAPTS TOLD ME THE SAME THING.

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.