As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
TRANSPONDER REPORTED INOPERATIVE. BENCH TEST REVEALED CAVITY TRANSMITTING AT 2,012 MEGAHERTZ AND IT COULD NOT BE ADJUSTED INTO TOLERANCE. FOUND TUBE INSTALLED WAS PC2080A, DATE CODE 99-13. INSTALLED BY FAA CRS AJVR135C, PRESENT MANUFACTURER (SIGMA-TEK) DOES NOT AUTHORIZE THE USE OF THE PC2080A IN THE TRANSPONDER. (X)