DAB integration?

[Dohmar]

[daviestar]

Bear with me, I'm buying all the necessary hardware to get Rune Audio set up, new to RPI

Which RPI do you guys recommend? Will using an RPI3 unnecessarily complicate things (as 64-bit)? From my 'carputer' perspective, the extra power, and maybe not needing to power an external USB hub, is a plus.. but can easily work around it.

Once I'm up and running and figure out how get in and hack RuneUI, I'd suggest working towards a simple 'Hello World' view, where we can type in the FM frequency to an <input> and stream the audio from that frequency.. thoughts? Or if DAB would be a better starting point, type in the name of the DAB station to grab the correct stream.

If we can get to this point, we should be in good place

[Dohmar]

RPI3 is the logical choice. It might not be 100% supported NOW but it will be.
Power is not an issue as the CPU scales its power determined by its load
Frank has already got FM working via command line for simple FM presets, its now a matter of extending that call and adding user interface stuff lime a freq search.

-D

[daviestar]

[Dohmar]

I'm really not sure. On SDR-J, the guy who wrote it runs the backend on his raspberry pi headless, and runs a frontend with a gui on another machine. I think we'll probably have to get someone to write a command line frontend to the pi's backend, and I'm no coder and have no idea about that stuff. I would suggest that the SDR-J software would contain the code required to pass to the backend daemon. I have no idea how it would work thought, its a little bit beyond me.

I think the other items you'll need are
SampleRate=2000000
BitRate=?

Re tuning - there are command line scripts on rtl-sdr's main site that scan a set frequency and then generate histograms that show the signal strength - the histograms are generated from a csv file that the command line tool spits out. You can set the granularity of the scan as fine or as wide as you want - In the case of consumer radio you'd want to do a scan thats thorough enough to reliably be able to locate radio stations but not so long the user will get bored (ie I ran a scan for an hour and it generated a rather large csv). In the case of live software I think you could probably pipe the output to grep or some other parsing software and the spit out the radio stations.

-D

[daviestar]

[Dohmar]

The sample rate on the onboard hardware is much slower than a dac hat. You'll need to reduce the sample rate section of the command line. Its getting fed too many samples and is playing them as fast as it can but it cant keep up.

-D

[daviestar]

[Dohmar]

Just a thought, but you might be able to quiz the RuneOS for what audio device is selected in the MPD config screen and then base the sample rate variable upon that. Ie is IQdacPI+ is selected, default to 192000, if its the onboard audio either 3.5mm or HDMI then you use 96000

-D

[daviestar]