Bendigo Amateur Radio and Electronics Club

Constructors Group

Circada Transceiver

 
This page and all descendants are under construction as of February 2025. Don't take what you see as the finished article. Check for changes occasionally.

What is it? Why the silly name?

It is a little CW transceiver, inspired by the Cricket transceiver, but powered by the silly idea "That I could graft a Si5351 on to it to make it tunable".



Of course, this means we need a microprocessor, lots of programming, a display and a rotary encoder for tuning. It is no longer the simple elegant thing that was "The Cricket". But it is still full Break In.

The receiver can hear 0.5uV (just), but because it is direct conversion, there is NO SELECTIVITY!. The transmitter puts out 1 watt (but can be pushed to 2 if you want to risk blowing the transmitter FETs with a dodgy antenna). Also, the design makes provision for up to 4 bands (but I haven't designed that board yet).

Schematic

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PC Board layout

Boards will be available from "The Club" when Phil gets his RRRs into gear. $5 for the main board & probably the same for the "3 extra bands" board.

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Component list

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