What was found
BURNING SMELL IN COCKPIT AND CABIN, AT SAME TIME HYD B-SYS PRESS DROPPED FROM 80 PERCENT TO 42 PERCENT. THE BURNING SMELL PLUS HYD PRESS DROPPED OFF DURING T/O AND CLIMBOUT AND THE SMELL DISSIPATED SOMEWHAT ON APPROACH. PER AMM 05-51-26-200-801C1 PERFORMED INITIAL OPS CHECK PART C STEP 9D THR S, NO FAULTS NOTED, EM02981. FOUND B-SYS QTY XMTR INTERMITTENT, REMOVED AND REPLACED XMTR PER AMM 29-33-12, LEAK AND OPS CHECK NORMAL RCM6584. FOUND SOURCE OF SMELL AT "A" LAV CALL BUTTON C/BOARD, REMOVED AND REPLACED C/BOARD REF AMM 33-27-00, OPS CHECK GOOD, LC45501, CONTINUED. COMPLETED SMELL IN THE CABIN INSP REF FIM 21-00-00-810-806, NO OTHER FAULTS NOTED. ROTABLE PARTS CHANGE WAS INDICATED - TT # 1274794 S/N OFF 01252 TRANSMITTER, HY OFF 29-2911-9-9001 1252 ON 29-2911-9-9001 2331.