[aprssig] transmit on heard

[Robert Bruninga]

>>> jdw at eng.uah.edu 05/28/05 5:39 PM >>>
>...driving through a ... sparsely populated area...
> I'm proposing a "TX on heard" 

A good idea in that case of hills and valleys where
it is frustrating to see one's fixed-timed posit go out
in a tunnel or valley.

But on the other hand, when you think about it, the
place where you need MORE transimssions is
where there is LESS to be heard..  I discovered this
on a western trip in southern Utah back before there
were any digis in that area.  I had my rate sent to
5 minutes since the difference between being 
somewhere in the middle of nowhere and somewhere
else 5 minutes away in the middle of nowhwere
didnt seem to be important.

But out of nowhere I heard one solid packet.  turned
out to be a trucker on an interestate.  But by the time
I figured it out, he was gone.  (Also no wayu to call
him because he did not have his freq in his posit).

>From that expereince I learned two thinkgs:

1) I invented VOICE ALERT so that we can ALWAYS
make voice contact withanyone running APRS and
voice alert.

2) I observerd that when in the wilderness one should
always set 1 minute rate!  In a passing situation on
an interstate at 60 MPH, you might get only 2 or 3
packets at most from someone.  At a 5 minute rate
you could be 10 miles apart and separating before
you heard each other...

So, the really "smart" beaconing idea I would suggest
the same rates, but change the paths as follows:

1 Hop:  DIRECT then WIDE1-1
2 Hop:  DIRECT, 1HOP, DIRECT, 2HOP
3 Hop:  DIRECT, 1HOP, DIRECT, 2HOP,  DIRECT, 3HOP
4 Hop:  DIRECT, 1HOP, DIRECT, 2HOP,  DIRECT, 3HOP, DIRECT, 4HOP

So for a 1 minute rate and a cross coutry trucker, he would
only be doing a 4 hop path once every 8 minutes, yet
we could see him close by...

de Wb4APR, Bob