Someone on QRZ forum has been giving me advice on my Class D design I am working on. I soldered the tiny, tiny parts onto their breakout boards - I should really avoid parts this small in the future...
I found in my design that the coefficient of mutual inductance plays a huge role in the performance, and I don't really know what that is reasonable to be. So I decided to make a 1:1 toroid and measure it (based on a procedure in EMRFD). However, I could not get my Banggood special inductance meter to work right. It has in the past, but no love tonight. So I decided to try the function generator/oscilloscope approach where I see where an inductor gives me half the voltage of a known resistor. Worked well for the primary/secondary windings, but couldn't get it to work for the other connections the book has me do. I assume the values are low and need to use a high frequency, and the frequency generator isn't very linear in its output over large ranges. May try some other method here soon.
I tried FT8 again tonight, but didn't get picked up by many receivers. I checked my signal into a dummy load afterwards (trying to figure out how much power I was putting out), and into a dummy load I was doing about a watt. However, I see that I am drawing half the power into the dummy load than I am into the antenna, so I should check that again. I might want to build a little matching network, even though the NanoVNA (the last I checked) seemed to show things fairly happy.
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