Wsprry on Pi and a filter.

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 So...

This was supposed to be a low-pass filter for 14MHz. It's not working well - or too well since no one can hear me!

I set up one of my Pi machines with the latest WsprryPi. I had used this successfully in the past, around 2014-2015. It does a square wave so needs filtering, done the filter above. It has a 49:1 UnUn built in so that I can plug it straight into a long wire antenna going around the study walls. Not perfect but it should radiate something.

Anyway, I can hear my signal on the FT-818, not very strong but audible and stable. It does definitely filter out at VHF, but I can still hear a meaningful signal on 29MHz, I guess it is attenuated enough so that it's not causing issues. I hate winding cores. It is stressful and not being able to measure them straight away is frustrating.

On the other hand, no one else hears me! I've been transmitting for a couple of days now, but not a single spot on the WSPR net DB. I have checked my frequency - it is OK, but PSK Reporter site only shows a handful of people listening on 20m. That is a problem. I guess most have moved away from WSPR to FT8 or others. I wonder what I can do to create such a beacon that can run on a headless system. Oh well, it was worth a try.

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