Plotting aircraft

[Dav43]

Hi Everybody, I need some knowledge. I have just started using the NavAir RadarBox and I am still going through a learning curve.
But one thing puzzles me. I am not getting a visual plot on the map until the aircraft is turning and going into land; or when it takes off I can plot it to 3000 then lose it off the plot (the globe disappears). The AirNav antenna is in visual sight of the aircraft so there are no obstructions. If I get a plot away from the airport it appears and then quickly disappears.
The myflights window continues to show the changing altitude of the aircraft, so I know it is being tracked.
The most common aircraft so far are Airbus A320-232 and Boeing 737-8FE and 738.
There are no filters on. Do need to do something or are these aircraft not transmitting plot coordinates on a continual basis.

Thanks
Dav

[Allocator]

Hi Dav, welcome to the forum!

I'm not entirely sure what is causing your problem and it's not one I've heard of before.  Aircraft are either transmitting position information, or they are not - so you should get consistant positions on the map.

When you say your antenna is in sight of the aircraft, where exactly have you got your antenna?

Also, might there be interference that could be affecting your reception?

You say that you can plot a departing aircraft until 3000 ft, does it ever appear again on the map as it climbs?  Can you see other aircraft all the way through the climbout?

Also, you say you are not getting the aircraft on the map until it is turning and going into land, what range and altitude is this?

Maybe a screenshot might help to understand your problem?

All the best

Allocator

[RodBearden]

Hi - is it possible that the aircraft are turning so that they are masking their own ADS-B transmissions, and the reception resumes when they stop masking themselves?

Rod

[newboy]

Help! I cannot see any plots moving on my map but I do have a list in my log which is constantly updating. Thanks

[Allocator]

Help! I cannot see any plots moving on my map but I do have a list in my log which is constantly updating. Thanks

Hi Newboy, a bit of thread drift maybe as this sounds like a different problem - but we'll carry on with your problem too :-)

Can you see anything in the MyFlights and Network aircraft lists - do you mean MyLog or MyFlights?

Any chance of a screenshot?

[Dav43]

Thanks for your help
Further to your queries
I have taken a screen shot of the moment before the aircraft goes off the plot at around 3400 ft. This is common for all departing aircraft. I watched this aircraft on the map, taxi out to the runway and takeoff so the signal is strong. I have also notice that just before the plot on the map disappears, the plot stands still yet the data still changes e.g. altitude, speed and then it disappears. At first I thought it might be a time out delay but data is changing on the aircraft plot. Furthermore I never lose contact with the aircraft as Myflights still register the change in altitude and in fact this is only contact I have with many the passenger aircraft coming and leaving Hobart Airport. About your question do they appear again? Yes. Some of the aircraft do appear around the 60 to 90 nm distance from airport varying altitudes of 2600ft to 36800ft normally climbing or cruising.
The same situation appears with approaching aircraft they just suddenly appear approx around the 13 nm from the airport. Yet I can plot aircraft some 150 km away from the airport.

The antenna is located outside on the balcony on a chair arm with visual sight of aircraft arriving and departing. We look east to the airport with a 2-3 mile wide river and low lying hills before the airport. No buildings or vegetation block the aircraft visibility till about approx 1000ft.

If it is something blocking the signal it has me puzzled. It is certainly not visible and does not relate to signal strength. You dont expect to be watching an aircraft visually and lose it off your map.

thanks

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[AirNav Support]

Dav43,

This is unusual however we think it may be to do with Radio equipment in the area where you loose plotting data of aircraft. Is there any Navigation beacons round there? If so what is there frequency? (These beacons sometimes have a high singal power in small area)

The signals are quite resilient to interference however what may be happening in this case is that as the position messages have more data they are more likely to be fragmented from interference.