The 291 through 294 series of SMD air wound coils are designed for high-power RF applications such as pagers, cell phones and mobile radios. Key specifications include inductance values from 1.65 nH ...
[Drew Pilcher] needed durable, custom-wound coils with no core, and perfectly flat sides. Coils can be wound by hand, of course, but reliably creating perfect coils with thin wire and lots of layers ...