I guess i'm right in thinking the answer would be NO for this but, does
anyone know if there is any software to decode the pulse tone sent out on
1090MHz by most aircraft. I know there is a company who sell a unit for
£500, which decodes onto a radar screen, this is what made me think that
there might be a bit more involved than just getting a hold of 'Free
Software' !.

Anyway, just like we can now decode pager messages, ACARS etc, i thought
maybe somewhere this software existed. I don't mean free software which will
place the aircraft on a radar screen, but just simple software which would
at least decode what flight number the aircraft was at least ?. I can pick
the signals up no bother, would be interesting to decode them !!

Cheers
Andy

On Sun, 9 Oct 2005 09:42:00 +0100, "Andy100" said in
rec.radio.scanner:

Anyway, just like we can now decode pager messages, ACARS etc, i thought
maybe somewhere this software existed. I don't mean free software which will
place the aircraft on a radar screen, but just simple software which would
at least decode what flight number the aircraft was at least ?. I can pick
the signals up no bother, would be interesting to decode them !!

Is the tone burst the flight number, or just the squawk number? (The
two aren't the same.)

If the format is known, the software can be written, if it hasn't been
already, but knowing that the aircraft is squawking xxx wouldn't tell
you much, unless they were declaring an in-flight emergency.

I assume the software has already been written. You can now buy a decoder
box and software which will give you a radar screen on your PC. See
http://www.airbandonline.co.uk/kapl_sbs1.htm. I think the box was just a
fancy scanner with 1090MHz aerial, something that may just be the same as a
scanner ?

Cheers
Andy


"Al Klein" wrote in message
...
On Sun, 9 Oct 2005 09:42:00 +0100, "Andy100" said in
rec.radio.scanner:

Anyway, just like we can now decode pager messages, ACARS etc, i thought
maybe somewhere this software existed. I don't mean free software which
will
place the aircraft on a radar screen, but just simple software which
would
at least decode what flight number the aircraft was at least ?. I can
pick
the signals up no bother, would be interesting to decode them !!

Is the tone burst the flight number, or just the squawk number? (The
two aren't the same.)

If the format is known, the software can be written, if it hasn't been
already, but knowing that the aircraft is squawking xxx wouldn't tell
you much, unless they were declaring an in-flight emergency.

"Al Klein" wrote in message
...
On Sun, 9 Oct 2005 09:42:00 +0100, "Andy100" said in
rec.radio.scanner:

Anyway, just like we can now decode pager messages, ACARS etc, i thought
maybe somewhere this software existed. I don't mean free software which
will
place the aircraft on a radar screen, but just simple software which
would
at least decode what flight number the aircraft was at least ?. I can
pick
the signals up no bother, would be interesting to decode them !!


You could just monitor the output of the detector with an oscilloscope.

Basically, they aren't tone bursts. There are two types of signal
transmitted depending on mode. One is a pulsed carrier containing binary
coded pulses 0.45uS wide. The other is a phase modulated carrier.

Most of the information transmitted is just numbers and if there are VFR
aircraft around, a lot of those numbers will simply decode as 1200, with an
altitude.

Brad