There are a lot of home brew SDR-related projects on the internet at the moment. I believe the key features of this project are:
- Small but conventional radio form-factor with tuning knob AND NO PC
- A clear graphical display with S meter and real-time band-scope/waterfall (very high update-rate makes the radio a pleasure to use)
- Smooth DDS tuning with steps down to 10Hz (optical shaft encoder)
- All mode operation with excellent SSB and CW filtering (NOT double-sideband) and a decent AGC
- There are no analogue components to adjust or align, so if built correctly the radio ‘will just work’
- Based on a very low cost, commercial CPU / Display board
- Cost of major parts is about £80 (UK) assuming stuff like a case, knobs, speaker, audio amp etc can be found ‘in the junk box’.
Please bear in mind that this project will require soldering of 0603-size SMD components and a couple of fine-pitched ICs (see photo of radio PCB below).
Please contact me at moc.dlrowltn@321ylbmit (reversed) or via qrz.com for information on getting a partial kit for the radio board. The parts kit comprises >90% of the passives, some of the ICs (3V3 regulator, the 26MHz TCXO and the ADC) and a PCB. (Note the PCB is now a proper 2-layer manufactured board with plated through VIAs, solder mask and silk screen. See here) Additional build documentation will be sent out by email and this includes the buying list for the remaining parts.
I am getting lots of email, so please check the FAQ before posting questions, thanks.
There is a failrly detailed walk-through of the radio and its features on YouTube here. There is also an older and less structured video here and various videos at the bottom of this page. (Please allow for the low bandwidth of my internet link!) Also see www.qrz.com/db/G0ETP
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