CTLR CLAIMS THAT RADAR GIVES ERRONEOUS MODE C READOUTS ON TARGETS IN VARIOUS AREAS.

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ACFT ON THE DADES ARR CONTINUALLY DISPLAY ERRONEOUS MODE C READOUTS WHILE ON DSCNT IN THE VICINITY OF THE DADES INTXN. ACR X; AN MLG; TCASII EQUIPPED; ALT 13300 FT; LEVELING AT 13000 FT; JUMPS TO A READOUT OF 76900 FT. ACR Y; AN LGT; LEVEL AT 13000 FT STARTS BLINKING 7600. ACR Z; AN MLG; LEVEL AT 12000 FT JUMPS TO A READOUT OF 17700 FT. THIS WAS RPTED TO AIRWAY FACILITIES. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR CLAIMS THAT THIS IS STILL AN ONGOING PROBLEM. THEY HAVE 2 RADAR SITES WITH 1 OF THEM DIGITIZED. THE ERRONEOUS MODE C GENERALLY HAPPENS WITH EVERY THIRD ACFT. MOST CTLRS HAVE BECOME USED TO WORKING WITH THIS PROBLEM; SO THERE HAS NOT BEEN ANY RPTED INCIDENTS. THE ERRONEOUS ALT USUALLY LASTS FROM 30 SECONDS TO 1 MIN. FACILITY IS TRACKING THE PROBLEM; BUT IT HAS BEEN ONGOING FOR ABOUT 3 YRS. UCR WAS FILED 4 WKS AGO. RPTR STATES THE FACILITY MGMNT IS GOOD TO WORK WITH; BUT THEY APPARENTLY DO NOT THINK THAT THIS IS A SAFETY ISSUE. TRACK DROPPING WAS ANOTHER PROBLEM FOR AWHILE; HOWEVER; AIRWAY FACILITIES DISCOVERED THAT A NEW BUILDING IS BEING CONSTRUCTED NEARBY WAS CAUSING THE PROBLEM AND ARE IN THE PROCESS OF RECTIFYING IT NOW. RPTR ALSO STATED THAT 2 FACILITY 'ARTS PROBLEM RPT' FORMS HAVE BEEN SUBMITTED ON THIS.