A line Mechanic reports he did not assure a B737-700 was recertified to CAT-3 status; after he was required to remove #1 and #2 Low Range Radio Altimeters (LRRA) for installation of test equipment to check the Aircraft Vibration Monitoring system (AVM).

Narrative

While accomplishing 'C' Check Task Card OPC landing warning for AVM system; we were required to perform the radio altimeter simulation test (Aircraft Maintenance Manual 34-33-00). This task required removal of both the #1 and #2 Low Range Radio Altimeter (LRRA) Receiver Transmitters to facilitate installation of test equipment. Upon completion of this task per the Aircraft Maintenance Manual; I did not assure that the aircraft was recertified to Category III status due to removal/installation of original LRRA System Receiver Transmitters. Although I did not release the aircraft; I did sign the task card and should have obtained a Category III qualified Technician to recertify the aircraft because I am not qualified. I contacted aircraft Maintenance Supervisor to report my mistake. Maintenance Control was notified and the aircraft was assigned to be recertified or downgraded per the Procedures Manual. This 'C' Check Task Card is normally accomplished at check and the aircraft is recertified to Category III prior to release from check. However; this card had been carried out of a check and accomplished on the line by me. Upon further follow-up; aircraft has been recertified to Category III status.