DIY Antenna Tuner 1 – 30 MHz
In China you can get a kit for an antenna tuner for about 10 €, which I once assembled for fun. Here is the link to buy it: Manuel Antenna Tuner DIY Kit 1-3 0 MHz
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The build was a little tricky because there wasn’t much room in the case. In addition to the parts included in the kit, I added two banana sockets. This is what my finished kit looks like.
Matching the antennas actually works quite well: tested from 160m to 12m.