[ARDF] 80m Testing in the Park...

[bruce]

On Sunday 13 February 2005 15:56, Matthew Robbins wrote:
> In Brno, I did the Park-O, and it's
> now clear to me that this 100kHz mode is designed for courses like
> that Park-O.

It might be useful as a means of determining the strongest TX from a certain 
location (ie. what do I do next?), but for actually DFing a particular TX I'd 
personally find a wideband *very* annoying/confusing with many close-by foxes 
on nearby channels.

> It sure makes a lot of sense now as a way to have a different sort of
> ARDF race.  And as a radio designed for races like that.

I enjoyed the race format a lot too. Not sure if I'm entirely with you on the 
receiver, however. Our receivers were the standard aussie (not the outdated 
BRG things!....sorry Ron) units.

> > The tone mode essentially modulates the receiver IF gain with a tone
> > that varies in frequency in steps depending on the gain control.  This
> > can be useful as a quick audio indication of overall signal strength
> > such as "Still very audible on lowest gain(tone)".   It is most useful

My temptation would be to vary the audio gain with the RF gain (as feedback) 
and vary the frequency with the signal strength (ie. the other way around).
Alternatively, vary the frequency with signal strength (as above), but vary a 
repetition rate (very low freq 'beat', or even better more like a PWM with 
constant off time but varying on time) with RF gain position. Just throwing 
in some ideas. The tone frequency you DF with, but you get feedback of how 
close you are a bit like a geiger counter.

Cheers,
Bruce