I think the nRF905 frequency can be programmed by a simple register write, so could be done 'on the fly' so to speak so could use a different channel to Flarm.
However, reading about the OpenFLARM project on another forum, the developers weren't aware that you can now use non certified GPS to enable ADSB out transponder.
Add to the fact that there is no barometer, I'm not sure if their subject knowledge is up to scratch, even if their soldering / software obviously is AND having another protocol is just crazy.
But £50 to RX Flarn instead of £600 for a mouse has its appeal.
Deker.
Indeed the frequencies are software selectable but that won't really help. To hear either the FLARM or their own protocol you would have to flip back and forth between frequencies, each takes some time to do. The underlying radio protocol relies on the receiver being able to determine the clock of the received signal by listening for a preamble, to recover the clock, then it will start to receive data. If you flip back and forth waiting to listen to both you will miss data from both.
I can only assume they are going to transmit their open protocol on the same frequency as the FLARM protocol, which given the congestion people already complain about when a few gliders are in the same area will just make things worse.
They also need to read the data sheet for their processor, the decoupling and clock are an example of how not to layout the PCB. I wonder if they have done *any* emissions or immunity testing at all? I suspect they simply believe they don't need to, which could be an expensive mistake to make.
Personally I'd have had both the coax connectors edit on the same plane too, rather than at 90 degrees to one another, that doesn't really help package wise - but that is how those radio modules arrive on the slow boat from china.