I did the math on RDF using 2 and 70 using difference time of arrival. The math worked out that I needed gps clocks to get accuracy down to a 50m with 4 receiving stations. However the gps clocks increased the price somewhat. I did not investigate the latency involved with RTL dongles or even if that latency could be fixed/measured which would be a key component. A dedicated radio may also need to be built to get RX carrier detection latency predictable. But in theory it would be possible to build a network with unlimited cheap RX stations reporting locations on a map APRS style from every received signal.
Matt
On 24/1/2022 5:11 pm, Tony Langdon via 44Net wrote:
On 24/1/22 5:48 pm, Steve L via 44Net wrote:
On Sat, Jan 22, 2022 at 11:14 AM Robert Simmons via 44Net 44net@mailman.ampr.org wrote:
Does anyone here have any interest in remote reporting radio direction finders ? ( RDFs )
I think if it can be developed as open source software using cheap hardware like the RTL-SDR (the kiwisdr is expensive), that would be a very good project worthy of an ARDC grant.
I agree. An RTL-SDR may or may not cut it (one way to find out ;) ), but open source software, and open and inexpensive hardware would be interesting to pursue.