Polar Diagram?

[Canonjohns40D]

Anyone help with this please. My aerial is currently the supplied one sitting on a window ledge inside. It is restricted but I get around 350 to 400 aircraft a day so happy enough. The polar diagram has been running for several weeks and it has a fairly regular pattern to it. I'm north facing so north or in front of me is better than my "blind spot" through the house to the south.
Tonight i clicked the diagram on and a spike to my south reaches down to around Plymouth. this distance is way in excess of my normal range North never mind a southerly direction. My question is is was this an aircraft and how did I pick it up. Can I use the position information to see what aircraft details appear for this position?

I would attach a screen shot if I knew how, any advice welcome.

Regards

John

[tarbat]

Probably an error in the position reported by the aircraft.  You could have a look through the Flights table in MyLog and identify a StartPosition or EndPosition in the Plymouth area - approx. N50.

For example, if I sort my Flights table by EndPosition, I see the following annomolies:
G-BUUR at N12 E0
N-144KK at N35 E135
G-BTPF at S42 E0
CS-DKB at S20 E118
HB-IVS at S25 E149
Etc........

On the Excel spreadsheet I use to view my polar chart, I ignore anything over 200 miles away.  And if you use sbsplotter, that can be configured to exclude plots over a certain distance away.