THE RPTR WAS CONDUCTING A PRACTICE ILS APCH TO RWY 19 WHILE THE VFR TFC PATTERN WAS USING RWY 01. THE ANNOUNCEMENTS WERE MADE AS THE RPTR UNDERSTOOD WAS CUSTOMARY AT THE ARPT FOR HIS ACTIVITY WHEN A PERSON BELIEVED BY THE RPTR TO BE THE UNICOM OPERATOR BROADCAST ON CTAF THAT THE PERSON ON FINAL ON RWY 19 SHOULD CHK THEIR RWY. THE RPTR SIDESTEPPED TO THE E AND ANNOUNCED HIS INTENTIONS. THE RPTR BELIEVED THE PERSON OTHER THAN THE PLTS BROADCASTING MADE THE ACTIVITY CONFUSING AND UNSAFE.

Narrative

I WAS FLYING A PRACTICE ILS RWY 19 AT PWT. RADAR SVC WAS TERMINATED AT CHECO (FAF) AND MY SAFETY PLT WAS ANNOUNCING OUR POS ON CTAF TO THE TFC IN THE PATTERN. RWY 01 WAS IN USE. THERE WAS AN OPPOSITE DIRECTION CESSNA IN THE PATTERN AS WELL AS A HELI ON THE W RAMP. THE USUAL PRACTICE IN THIS CASE IS TO ADVISE THE OPPOSITE DIRECTION TFC THAT THE AIRPLANE ON THE ILS HAS THEM IN SIGHT; AND WILL BREAK OFF THE APCH EARLY AND SIDESTEP TO THE E (THE ALTERNATE MISSED APCH IS 070 DEGS MAINTAIN 2000 FT). IF THE OTHER ACFT DOESN'T ACKNOWLEDGE; THEN THE APCH WILL BE BROKEN OFF SOONER RATHER THAN LATER FOR EXTRA SAFETY. IN THIS CASE ANOTHER VOICE BROADCASTED ON CTAF THAT THE AIRPLANE ON FINAL SHOULD CHK THE RWY. I WAS ABOUT A MI FROM THE RWY (THE OTHER ACFT HAD JUST LIFTED OFF) SO I SIDESTEPPED TO THE E; AND ANNOUNCED MY INTENTIONS. THIS USUALLY WORKS WELL; BUT WHEN SOMEONE OTHER THAN THE PLTS OF THE AIRPLANES INVOLVED STARTS BROADCASTING ON CTAF IT BECOMES CONFUSING AND UNSAFE. I THINK THE UNICOM OPERATOR MAY BE DOING THIS BUT IT REALLY IS OBTRUSIVE. I WILL NOT DO OPPOSITE DIRECTION APCHS AT PWT UNTIL I CAN GET THIS RESOLVED.