Narrative:

I had departed pne en route to 19N then onto 17N for a transponder check. I landed at 17N, had the transponder check done and everything was ok. Then I started up the aircraft, made sure the transponder was on, but overlooked the squawk code that the technician used to perform the check (7700). I proceeded to the runway, performed my takeoff checklist and failed to squawk 1200. Then took off to return to pne, 'the same route,' then 7 mi south of pne I contacted the tower, stated my intentions and that's when the tower told me to squawk 1200 and identify. At that moment I realized that I had been flying along squawking 7700. I then squawked 1200 and idented. The controller asked me if there was a problem and I told him that everything was ok. I was then cleared to land and did so then the controller cleared me to the ramp. I expected, but was not asked, to contact the tower. Callback conversation with reporter revealed the following information: this pilot said that he normally checks the transponder as part of his preflight check on the C-150. He assumed that the maintenance facility technician would leave the transponder on the proper setting when his check was complete. The pilot did a preflight for the return flight, but simply turned on the transponder without checking the setting.

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Original NASA ASRS Text

Title: XPONDER OP PROC. PLT HAD CODE 7700 IN HIS XPONDER FOR THE WHOLE RETURN FLT FROM A MAINT FACILITY.

Narrative: I HAD DEPARTED PNE ENRTE TO 19N THEN ONTO 17N FOR A XPONDER CHK. I LANDED AT 17N, HAD THE XPONDER CHK DONE AND EVERYTHING WAS OK. THEN I STARTED UP THE ACFT, MADE SURE THE XPONDER WAS ON, BUT OVERLOOKED THE SQUAWK CODE THAT THE TECHNICIAN USED TO PERFORM THE CHK (7700). I PROCEEDED TO THE RWY, PERFORMED MY TKOF CHKLIST AND FAILED TO SQUAWK 1200. THEN TOOK OFF TO RETURN TO PNE, 'THE SAME RTE,' THEN 7 MI S OF PNE I CONTACTED THE TWR, STATED MY INTENTIONS AND THAT'S WHEN THE TWR TOLD ME TO SQUAWK 1200 AND IDENT. AT THAT MOMENT I REALIZED THAT I HAD BEEN FLYING ALONG SQUAWKING 7700. I THEN SQUAWKED 1200 AND IDENTED. THE CTLR ASKED ME IF THERE WAS A PROB AND I TOLD HIM THAT EVERYTHING WAS OK. I WAS THEN CLRED TO LAND AND DID SO THEN THE CTLR CLRED ME TO THE RAMP. I EXPECTED, BUT WAS NOT ASKED, TO CONTACT THE TWR. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THIS PLT SAID THAT HE NORMALLY CHKS THE XPONDER AS PART OF HIS PREFLT CHK ON THE C-150. HE ASSUMED THAT THE MAINT FACILITY TECHNICIAN WOULD LEAVE THE XPONDER ON THE PROPER SETTING WHEN HIS CHK WAS COMPLETE. THE PLT DID A PREFLT FOR THE RETURN FLT, BUT SIMPLY TURNED ON THE XPONDER WITHOUT CHKING THE SETTING.

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.