BASIC Tech Group - MyNews 32 - JT65 on Arduino

A quick look on 40m shows a lot of JT65 comms taking place. Here's the picture as received by the WEB SDR at Hack Green



And the decode using the program JT64-HF running under Wine on my iMac. By the way I use the expensive, but TERRIFIC program called Loopback to send audio from my Safari browser to JT64-HF, works a treat.



I am working on a Arduino Sketch to generate JT65, but am a bit bamboozled by the Reed Solomon encoding at he moment and things aren't working...

Arduino

So I have ported the code Si5351_JT65 downloaded from the internet, and have adapted it for the AD9850 Synthesiser. It was quite terrifying as it contains lines and lines of code that I simply do not understand - especially the part doing the Reed-Solomon error correction calculations.

Anyway these are the results. First a photo fo the Arduino Shield, note that I have plugged in an RTC (DS3231) module to give me real time and allow message start on the minute,



And here are the SDR received signals using HDSDR running under Wine on my iMac, and feeding the audio to JT65-HF also running under Wine on the iMac.





I have yet to code the messagess that are commonly used in JT65 QSOs for CQ and replies.

Code

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