Receiving FT8 With a Pixie.

After a long wait I received some crystals for the FT8, JS8Call and WSPR/QRSS frequencies on 40m and 20m, ordered some time in March.

The Ebay seller was not at fault, I suspect that the COVID-19 situation had left the package stranded somewhere on the way, for a long while. Other packages from the USA have not arrived yet, either, but who knows, they may appear one sunny day.

One set of crystals has 3 crystals per band:

7074kHz (FT8)

7078kHz (JS8Call)

7038.6kHz (WSPR/QRSS)

14074kHz (FT8)

14078kHz (JS8Call)

14095.6kHz (WSPR/QRSS)

In previous posts I have written about some experiments with the Pixie kits, and now is the opportunity to continue with that

The original 7023kHz crystal was unsoldered and a 7074kHz crystal soldered in. I am leaving the long leads at the crystal, as I think I will use it for a different receiver (or, maybe a transceiver). The frequency was adjusted to 7074.00kHz, so the test could begin. During the day not too many signals were heard, but in the evening the signals are coming in very nicely.

The antenna is a low hanging 10-15-20-40-80m dipole, so not the best, but this is excellent for the test.

Connecting the Pixie to the antenna and a set of computer speakers, FT8 signals were heard, immediately.

A quick test with a laptop, using its microphone, yielded immediate FT8 spots. A USB sound interface was found and connected in place of the speaker/microphone, and the spots poured down the screen. In the span of less than 2 hours spots were seen from North and South America, Europe, Africa and Asia. 

The system is actually working.

I left the system running over night, and in the morning I could add Oceania to the list (Indonesia). No Australia or New Zealand, but that was to be expected at this time of the year.

The experiment is a success, so now I consider the next step:

- setting the same receiver up with a raspberry Pi running headless, but using VNC, or

- inserting the 7038.6kHz crystal and setting up with a Raspberry Pi for QRSS, and maybe also WSPR.

If I just set the Pixie up for QRSS with an older Raspberry Pi, this could make for a low power, solar powered QRSS grabber system, so that is a tempting option.

Further steps could be a low power DSB or phasing SSB transceiver for FT8 or JS8Call, at first for 40m, later for 20m.

Now, if I could find a corresponding set of crystals for 60m or 80m, that could be interesting, too. On 80m, however, I could possibly use a ceramic resonator and tune it to the FT8 frequency (3573kHz). For the JS8Call a standard NTSC colour crystal (3579kHz) could be used, re-tuned to 3578kHz. It *may* be possible to use a Super-VXO (2 or more crystals in parallel) type oscillator for generating the 3573kHz signal.  

As always, too many ideas, but it is never boring.