D8 FLC FAILS TO CONTACT TWR. LANDS WITHOUT CLRNC.

Narrative

WHILE BEING VECTORED FOR TFC COMING IN FROM THE S TO PDX INTL WE WERE TRANSFERRED FROM ONE APCH CTL FREQ TO ANOTHER; 126.0; WHICH WE HAD NEVER USED BEFORE. THIS CTLR TOLD US WE WERE TO STAY WITH HIM ALL THE WAY 'IN.' THEN HE BEGAN TO VECTOR US FOR SEVERAL TFC WATCH ACFT THAT WERE OVER DOWNTOWN PORTLAND AS WE WERE LINING UP FOR RWY 3. HE NEVER TOLD US TO CONTACT THE TWR ANYWHERE ALONG THE WAY; AS THERE ARE NO LANDMARKS; BEACONS; OR SUCH YOU USE FOR A KEY ON THIS VISUAL APCH. WE CONTINUED OUR APCH AND GOT INVOLVED IN THE CHKLIST AND SUCH AND AFTER WE TOUCHED DOWN AND TURNED OFF WE WENT TO CONTACT GND; BUT NOTICED THAT WE HAD NEVER TALKED TO TWR. THE KEY WORDS; 'CLRED TO LAND'; NEITHER MY FO NOR I CAN REMEMBER HEARING. WE THEN CONTACTED GND CTL AND THEY JUST GAVE US TAXI INSTRUCTIONS TO THE GATE; ETC. NORMALLY IF YOU DON'T CALL THE TWR YOU GET THIS VOICE THAT ASKS YOU THE QUESTION. 'DID YOU GUYS GET CLRNC TO LAND???' BUT THAT DIDN'T HAPPEN. WE TAXIED ON IN AND AS I THOUGHT ABOUT IT LATER I CALLED THE TWR SUPVR AND ASKED HER ABOUT THE SIT. SHE MENTIONED THAT THERE MUST HAVE BEEN A MISSED HDOF DURING THAT TIME; AND THAT THE FREQ 126.0 WAS SOMETHING NEW THAT THEY WERE JUST TRYING THAT DAY TO HELP VISUAL TFC FOR RWY 3; WHILE RWY 28L IS CLOSED. BUT AFTER WE LANDED WE SAW AN MD11 LAND ON RWY 28L. EVEN THOUGH WE HAD JUST GOTTEN ATIS THAT IT WAS CLOSED. THE TWR SUPVR DID NOT REMEMBER ANYTHING SPECIAL ABOUT THE TIME WE LANDED. NO BELLS OR WHISTLES HAD GONE OFF; SO MAYBE IT WAS JUST MISSED BY ALL. SOMETHING TO THINK ABOUT; BUT I WANTED TO LET SOMEONE KNOW WHAT HAD HAPPENED WHILE USING THIS NEW FREQ ON A SELDOM USED RWY. I HAVE MADE HUNDREDS OF LNDGS AT PDX OVER THE LAST 9 YRS; BUT I CAN COUNT ON ONE HAND THE NUMBER OF TIMES I HAVE USED RWY 3. THIS WAS A D8 SCHEDULED ARR FROM MEDFORD; OR.