Receiving further than 250 NM

[AirNav Support]

We have been getting a few queries from people who sometimes say there reception various a lot and few in areas like the Middle East who get very large polar diagrams (not caused by erroneous messages)

Some of this can be explained due to Tropospheric bending of UHF.

Have a read of the site below for some interesting distances:

http://en.wikipedia.org/wiki/Tropospheric_propagation

Then take a look at the forecast near you :)

http://www.dxinfocentre.com/tropo_eur.html

[OKC-Steve]

The reason you don't normally see long range targets, is they get swamped by the closer-in targets.  As the amplitude of close-in targets raises the threshold of the minimum power detection level.

If you had a rotating antenna, with few sidelobes, you could probably extend your range on a daily basis, but it's not really worth the trouble, as 100 miles is plenty.

The whole reason for having a network share, is so users don't have to have long range.  Alas, the receivers and share prices are too great yet to attract the number of users required to make networking feasable.

[Allocator]

The whole reason for having a network share, is so users don't have to have long range.  Alas, the receivers and share prices are too great yet to attract the number of users required to make networking feasable.

Not within Europe it isn't, the Network coverage is excellent :-)

[VK2GEL]

My record is 722nm:

www.qrz.com/db/vk2gel

[jannuh]

Exceptional reception of VHF/UHF and SHF in the Med and PG (Persian Gulf) is a well known fact, but those conditions are always over the sea, it is knwon that over desert area V/H/S-HF is rather poor.
See the dxinfocenter.com site for additional information or google on "tropo".

On 162 mHz (AIS) my record is over 900 nm, normally my range is about 12-15 nm (my  coverage is inland shipping), ais-url: http://www.marinetraffic.com/ais/stationdetails.aspx?station_id=263&header=true