A DC9-80 WAS DISPATCHED IN NONCOMPLIANCE WITH THE #1 COM TUNING SELECTOR MALFUNCTIONING AND DEFERRED IN CONFLICT WITH THE MIN EQUIP LIST.

Narrative

OUR ACFT WAS ARRIVING WITH OTHER CREW. AFTER TALKING WITH CREW LEAVING THE ACFT; WE DID OUR PREFLT AND DUTIES IN ORDER TO DEPART. WE NOTICED OUR ACFT #1 RADIO (WITH 2 HEADS) HAD A TUNING PROB ON THE 'B' SIDE. THE KNOB WOULD ONLY GO UP OR DOWN TO CERTAIN SPOT THEN STOP. THE FREQ (WE DISCOVERED) WAS OFF BY .10 DECIMALS. WE CALLED MAINT TO FIX SAID RADIO. THEY GAVE US AN 'ENRTE' MEL. AFTER HEARING WHAT THEY TOLD US TO WRITE; WE TOLD THEM THAT THE XFER SWITCH WAS WORKING AND THE PROB WAS THE TUNING KNOB. THEY GOT IT STRAIGHT AND GAVE US A NUMBER OF THE MEL (NEW ONE FOR THE PROB). WE LOOKED IT UP IN THE MANUAL AND READ IT TO BE CORRECT. HOWEVER; THE TITLE OF THE MEL ONLY ADDRESSED THE NUMBER '2' RADIO. THE ACFT #1 RADIO HAPPENS TO BE ON THE EMER BUS. THE RADIO WE HAVE IN CASE OF LOSS OF ALL NORMAL PWR! WHAT SURPRISED US WAS THAT WE DID NOT THINK ABOUT LOSS OF ALL NORMAL PWR WOULD TAKE OUT THE #2 RADIO; BECAUSE THAT'S WHAT WE HAD. I MENTION THIS BECAUSE WE WERE THINKING THAT WE STILL HAD THE 'A' SIDE OF THE ACFT #1 COM (ONLY THE 'B' SIDE OF COM #1 WAS INOP). IT DAWNED ON US ONLY AFTER THE MECH CAME IN AND CHANGED OUT THE ACFT #1 RADIO AFTER WE LANDED (AFTER THE WRITE-UP AND SUBSEQUENT MEL.)