Narrative:

When enroute to O61 on flight following with oak center I was handed off from one oakland center controller to another. After being handed off I reported 'level at 9;500 starting VFR descent.' controller's response was 'traffic at 12 o'clock [at] 9;500.' [I] descended below 9;000 ft. Then [controller transmitted] 'to avoid traffic turn left 15 degrees.' [I responded] 'left turn 15 degrees.' I [was] now at 8;800 ft and started my left turn and [at] 10 o'clock; 100 ft [away] and below me 200 ft [was] the cessna traffic traveling southeast [which then] passed under us. Traffic was also on with center. A few minutes later I asked the controller if the cessna was squawking mode C and he responded 'positive; level at 9;500.' I have [had a] static pressure test on this aircraft in the last 4 months. Please review this; it seems that a few mistakes were made on where the traffic was and [his altitude]; and I was asked to turn directly into the other aircraft and descend through him.

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Original NASA ASRS Text

Title: BE36 pilot reported NMAC with a Cessna on flight following with OAK Center.

Narrative: When enroute to O61 on flight following with OAK Center I was handed off from one Oakland Center Controller to another. After being handed off I reported 'level at 9;500 starting VFR descent.' Controller's response was 'traffic at 12 o'clock [at] 9;500.' [I] descended below 9;000 FT. Then [Controller transmitted] 'To avoid traffic turn left 15 degrees.' [I responded] 'Left turn 15 degrees.' I [was] now at 8;800 FT and started my left turn and [at] 10 o'clock; 100 FT [away] and below me 200 FT [was] the Cessna traffic traveling SE [which then] passed under us. Traffic was also on with Center. A few minutes later I asked the Controller if the Cessna was squawking Mode C and he responded 'positive; level at 9;500.' I have [had a] static pressure test on this aircraft in the last 4 months. Please review this; it seems that a few mistakes were made on where the traffic was and [his altitude]; and I was asked to turn directly into the other aircraft and descend through him.

Data retrieved from NASA's ASRS site as of July 2013 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.