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README.md

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 # induct
 Calculators and utilities for real-world electronic design
+
+## iloc
+iloc.c is a very simple calculator program for designing single layer air coils,
+including space wound coils having a length equal to or greater than their
+diameter. For single turn inductances and short coils, I encourage you to
+consult the fine work of the late Nagaoka who published tables and formulas for
+his correction coefficient. This was not a concern for the scope of this simple
+calculator as such inductances are not seen or desirable outside of antenna
+systems or above UHF frequencies. I may decide to revisit this should the need
+arise.
+
+Most calculators found online need either length or turns count to generate a
+result. As they are both mathematically related, this has been simplified to a
+single term in the form of turns spacing. Thus all that is required is target
+inductance, diameter, and the turns spacing value to derive both length and
+turns count. I have found this much easier when designing coils, especially
+spacewound coils.
+
+Eventually the capability to output capacitance and self resonant frequency
+would be ideal, however the available formulas do not appear to be accurate
+enough to produce a result that would allow one to design and build a component
+such as a trap with any kind of accuracy. Maybe it's asking a bit too much right
+now. Taking it slow and careful with the incremental progress thus far is
+producing some results albeit at such a glacial pace.
+
+Some credit is due to Samuel Goldwasser et al. whom distribute the coil.c which
+is used as a template to provide ui and output formatting.
+
+## tankfreq
+tankfreq.c is another very simple program which will calculate LC tank circuit
+resonance frequency as might be expected. 
+
+## elcut
+elcut.c is a very very simple calculator designed as an antenna tuning aid. It
+will give the estimated length to remove from a wire in order to bring it to the
+desired resonance frequency as entered. It is recommended never to remove the
+exact amount given but instead gradually and carefully reach the resonant
+length. As in the oft repeated words of Guy Wireson (whom has died), "You can
+take more off but you can't put more back on." If you don't think that's funny
+at least consider it my gift to you as the only person who will ever read this.