My understanding is that there used to be more timely overlap between commercial and amateur radio technology — e.g. helping study ionospheric propagation, relatively early adoption of SSB technology, up through re-purposing business equipment for voice and packet use on 2m/70cm bands.
But now as a ham I feel like knowing about Baudot and "varicode", setting up an APRS bridge, WinLink and EchoLink…? These might be interesting from a historical/cultural perspective, but hardly overlaps what I might learn from a wireless engineering curriculum nowadays. I guess I could buy a shiny D-STAR/WIRES-X setup and send lo-res pictures of the sunset through a local repeater — but given that the underlying AMBE patent expired last year, I'm not sure how much that does to "advance the state of the radio art"!
My impression is that the ham world lost its connection with the commercial wireless "side" when that market largely shifted from business bands over to cellular service providers and standards. I know hams are able to re-purpose Wi-Fi equipment and some ham groups have worked on interesting projects like HSMM-Mesh — is there any similar effort using cellular specifications and equipment?
I guess this would entail things like:
- Are there any cellular bands that are close enough to amateur allocation for off-the-shelf cellular modems/filters/antennas to work?
- Does any relatively modern generation of cell technology have enough public datasheets for home/hobby use?
- Can baseband chips be configured sufficiently to e.g. disable encryption and enable identification as usually required by amateur licensing?
For example, I have an old Firefox phone where most of the OS is open source, and I know the SDR/security/open-source crowds have been playing with base station deployments for a while (e.g. OpenBTS) but I am unsure what licensing regime if any they are working under. Is the underlying phone hardware flexible enough that hams could convert it for use under amateur radio guidelines?