[aprssig] Fillin digi experiment

[Tapio Sokura]

Phillip wrote:
> If the same beacon is heard being digipeated by one of the wide area
> digipeaters within the 15 second period, the buffer is erased and the frame
> is not digipeated. If no digipeat is heard, the frame is digipeated and the
> buffer is erased so it becomes available for another frame.

I think there was some discussion about this "vicious" type of 
digipeating here a couple of months ago. There are digis in existance 
already that implement a similar algorithm and they work pretty nicely 
capturing those packets that the big guys don't hear.

A key parameter here is the waiting period, 15 seconds sounds like a 
pretty long time to hold on to a packet before digipeating it. I'd 
prefer something under 10 seconds.

   Tapio