Author Topic: Help diagnosing false positives  (Read 185 times)

marioair

Help diagnosing false positives
« on: July 25, 2020, 11:15:14 am »
first post covid flight in a while yesterday and was seeing a lot of false positives (looked like bearingless mode C).
is there a set of steps i should follow to check why i was seeing these?

the call signs seemed to be odd too - ST11, ST12.  I was near Stapleford at the time - are these student call signs? Neverthless they were defineyly false positives to the point where I wanted to pull the plug as it was distracting 

Admin

Re: Help diagnosing false positives
« Reply #1 on: July 25, 2020, 01:49:15 pm »
Bearingless mode c does not provide an icao code
This means if really st11/12 then they were mode s
What are your bearingless settings, can you share the configure page
Thx
Lee

marioair

Re: Help diagnosing false positives
« Reply #2 on: July 25, 2020, 10:39:21 pm »
I’ll grab the logs next time I’m at the plane - shame there’s no client app to save logs as I leave the PaW tucked away! :o

Yeah i can remember for sure the Mode but i defiantly has Call signs reporting 100 feet above or 200 feet below

ST11
ST12
G-SLCT

Admin

Re: Help diagnosing false positives
« Reply #3 on: July 26, 2020, 08:14:19 am »
Thanks
When you say ‘false positives’, do you mean that you do not think they were in your vicinity- either laterally or vertically, and hence was false reporting?

The vertical element will be absolutely correct assuming their altitude encoder is correct, and your baro is reading correct
The lateral element will be somewhat dependent upon your Installation and settings
Thx
Lee

marioair

Re: Help diagnosing false positives
« Reply #4 on: July 26, 2020, 09:06:11 am »
It was a busy stage of flight but I recall quite a few “traffic 100 feet above or 200 feet below” with no bearing.

I have snipped the original antenna down to half length.

I suspect it may be the setting dialled up too high but I’ll check and report back

Keithvinning

Re: Help diagnosing false positives
« Reply #5 on: August 03, 2020, 09:34:20 pm »
Hi Marioair

G-SLCT is a diamond aircraft. What is the registration of your aircraft

Regards

Keith