Things I Learned: Human Thumbs Look Like Capacitors to Low Level High Frequency RF

OK, so this isn't so much one I learned, as one I remembered, and then empirically proved.

Did you know that human thumbs are capacitative—as in they act like capacitors? Yup! They are!

The project TouCans Rockmite/TunaTopper stack suffers from the same issue the Flying Rockmite often did. Sometimes, the RFI from the antenna gets to be too much, and the memory keyer decides to stop keying out its memory. I noticed that when using the keyer with Project TouCans, if I put my thumb across the leads to the 'dah' keyer switch, the issue went away and the memory keyer ditted and dahed along to completion. I had brought a small capacitor out to the radio site to try placing across the headphone leads to solve an AM pickup problem inherent with having 25 foot long headphone wires. The same issue on a far lesser scale had been solved by Mark—N6MTS—as part of his work on the Open Headset Interconnect Standard, OHIS. The cap hadn't down the job for the Flying Rockmite or Project TouCans, AM signals sometimes wander in. What the cap did do however, was nicely replace my thumb.

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Copasetic Flow

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