Narrative:

20 NM southwest of mile high VORTAC started a descent from 11500 ft on a northeast heading to 7000 ft MSL. At the mile high 235 degree radial at 18 NM (EST) a report from approach called traffic southeast 1 mi at 7500 ft heading northwest. Then approach changed me over to approach on 126.1. I said thank you for traffic and switched to 126.1. On the switch-over I saw aircraft fly under me 150 ft (EST) horizontal and 50 ft vertical in a hard left turn. Other aircraft told approach about the event. I remained silent because of major traffic on the frequency. When approach reported traffic 1 mi southeast of 7500 ft I was at 7850 ft. I leveled at 7850 ft during the switch-over to approach on 126.1. Approach never questioned me about the event.

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Original NASA ASRS Text

Title: SMA INBOUND TO DVV VOR WAS GIVEN TFC INFO ON A VFR C210 AT 7500 FT HEADING NWBOUND. ACFT PASSED APPROX 50 FT VERTLY AND 150 FT HORIZLY. NMAC. SEE AND AVOID CONCEPT.

Narrative: 20 NM SW OF MILE HIGH VORTAC STARTED A DSCNT FROM 11500 FT ON A NE HEADING TO 7000 FT MSL. AT THE MILE HIGH 235 DEG RADIAL AT 18 NM (EST) A RPT FROM APCH CALLED TFC SE 1 MI AT 7500 FT HEADING NW. THEN APCH CHANGED ME OVER TO APCH ON 126.1. I SAID THANK YOU FOR TFC AND SWITCHED TO 126.1. ON THE SWITCH-OVER I SAW ACFT FLY UNDER ME 150 FT (EST) HORIZ AND 50 FT VERT IN A HARD L TURN. OTHER ACFT TOLD APCH ABOUT THE EVENT. I REMAINED SILENT BECAUSE OF MAJOR TFC ON THE FREQ. WHEN APCH RPTED TFC 1 MI SE OF 7500 FT I WAS AT 7850 FT. I LEVELED AT 7850 FT DURING THE SWITCH-OVER TO APCH ON 126.1. APCH NEVER QUESTIONED ME ABOUT THE EVENT.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.