[aprssig] transmit on heard

Jason Winningham jdw at eng.uah.edu
Sat May 28 17:39:11 EDT 2005

As I was driving through a hilly, sparsely populated area in TN this 
week, I turned up the audio on 144.39 to see how much traffic there 
was, and so I could cause the D700 to beacon when I heard traffic 
(under the assumption that they would be more likely to hear me if I 
could hear them).

After a half a dozen times, I thought "it sure would be nice if the 
radio could do this for me."  So, I'm proposing a "TX on heard" 
feature.  It may not be a new idea, but none of the hardware or 
software I've worked with has  it.

It could operate as the sole method of causing a position TX, instead 
of using a timer, or it could be integrated with some sort of Smart 
Beaconing (tm whoever those 2 guys are).  The OpenTracker has an 
"energy detect" circuit, so it could probably do this even though it 
has no true receive capability, as could other similarly equipped 

You'd probably want some sort of random delay between the heard traffic 
and the TX, in case someone else is operating in the same mode.

Now I'll sit back and let everyone tell me that it's already been done, 
or why it's a bad idea. (:


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