2.4 GHz Unlicensed Band

Figure 1: Status and printDetail() screen of the pingpair_dyn sample app (click to enlarge).

Finally, the unlicensed band nRF24 devices are talking to each other!  It was a bit of a road trip.  One thing to note is the importance of the status byte, and the other status data.  While a hex 0x0e is normal, a hex 0x00 in the status byte, and/or lots of zeros in the printDetail() output are pretty good indicators that your SPI is not operational, and you’re not talking to the transceiver.  More on this issue follows …

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SoC/SBC Boards for Ham Radio

Figure 1: Various combinations that have, thus far been considered for ham radio audio duty (see text for explanation).

For the past couple years, I have been attempting to determine what might be the best platform for ham radio and other communications related applications, with a bias projected towards looking at mobile platforms. The graphic (above) shows a few options that I have seriously considered, and a couple for which I have built prototypes to aid in the testing process. The graphic is not intended to imply any capability or lack of capability with respect to the hardware, the SoC chip based SBC boards, or the operating systems. The selection only implies what I have made as a personal preference, for reasons that (shortly) – I’ll enumerate. In other words, the Raspberry Pi may use USB Audio, but I would prefer I2S if I can make it work.  Many alternate combinations are possible, and I have refined a list of preferences for the audio configurations I’ll use.  I have more info about this subject at:

https://programmingmiscellany.wordpress.com
(The link goes to another of my blogs)

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