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Mar 4, 2023Liked by Steve Stroh N8GNJ

Here's a DC-1.8GHz front end for a software defined radio transceiver. Just add 10Gbps Ethernet, and back end server. Runs on 75 Ω though. DOCSIS remote PHY hardware can build a channel map with different carrier modulation and agile frequency mapping. Probably way out of most amateur repeater budgets though.

https://www.harmonicinc.com/broadband/pebble-2-device/

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Ready - Agreed that "cable television" infrastructure has been a pioneer in the use of very broadband (1 MHz through 1 GHz) "radios"... but they don't make it easy to use for Amateur Radio (though several folks have tried).

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Mar 9, 2023·edited Mar 9, 2023

Yea, that was a little bit tounge in cheek. But large FPGAs exist and are being mass produced. Comcast was on the way to building out a "passive coax" cable upgrade that would not have any amplifiers between the optical node and customer, until somene came up with a fancy amp that can do active echo cancelling (itself likely using an FPGA to perform the complicated math) that will be necessary for duplex OFDM. Like other SDR projects programming FPGAs is beyond most amateurs' capabilities and I don't think there's a really friendly way to change that right now. Short of some big player releasing their library to Github so that the amateur community can use the low-level stuff as building blocks. But so much of that is the "secret sauce" that keeps them in business.

And then there's always the risk of having to deal with the ITAR boys...

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