[Hackaday] The Simplest FT8 Transceiver Youll Ever Build

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amateur radio - Hackaday

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The Simplest FT8 Transceiver Youll Ever Build

Posted: 25 Sep 2021 07:00 PM PDT
https://hackaday.com/2021/09/25/the-simplest-ft8-transceiver-youll-ever-build/


Probably the most interesting facets of amateur radio in 2021 lie in the
realm of digital modes. Using the limitless possibilities of software
defined radios has freed digital radio communication from the limits of
what could be done with analogue electronics alone, and as a result this is
a rare field in which radio amateurs can still be ahead of the
technological curve. On of these newer digital modes is FT8 created by the
prolific [Joe Taylor K1JT].

And its for this  mode that [Charles Hill] has created an easy-to-build
transceiver. Its brains are aTeensy 3.6, while the receive side is a Si4735
receiver chip and the transmitter is a Si5351 programmable clock chip
driving a Mini-Circuits GVA84 power amplifier with an appropriate filter.
The interface is via a touchscreen display. It relies on existing work that
applies a patch on-the-fly to the Si4735 receiver chip for SSB reception,
and another project for the FT8 software.

The charm of this transceiver is that it can be assembled almost in its
entirety from modules. Some radio amateurs might complain that homebrew
radios should only use the most basic of components assembled from first
principles, but the obvious answer to that should be that anything which
makes radio construction easier is to be welcomed. If the 100 mW output
power seems a bit low its worth remembering that FT8 is a weak signal mode,
and given the right propagation conditions the world should be able to hear
it despite the meagre output.

Weve featured quite a few radios using the Si47XX series, which can be made
into very tidy receivers indeed.