What was found
HF RADIO 2 SHOWS FAIL IN ACTIVE AND STANDBY DISPLAY. NORMAL FREQUENCY AND DATA INDICATIONS ARE DISPLAYED MOMENTARILY WHEN ADJUSTING SENSITIVITY. THEN REVERT TO FAIL CALIBRATIONS. RADIO FREQUENCIES APPEAR TO OPERATE NORMALLY. ACFT GROUNDED. ACCOMPLISHED A NR 2 HF COMM SYSTEM BITE TEST IAW FIM 23-11, TASK 801, & HF COMM SYSTEM RECEIVE & TRANSMIT FAULT ISOLATION IAW FIM 23-11, TASK 806, NO DEFECTS FOUND. REMOVED & REPLACED THE NR 2 HF TRANSCEIVER AS PRECAUTION IAW AMM 23-11-21, GROUND VERIFICATION TEST NORMAL IAW AMM 23-11-00-730-801. PULLED & RESET 1 CIRCUIT BREAKER IAW AMM 23-12-41-800-802.