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NMSU Builds Ham Radios

I just saw this on the GQRP list courtesy of Trevor, M5AKA. Students at my old stomping grounds, New Mexico State University are building QRP tranceivers. They're being assisted by Bob Hull who manages the capstone projects program. Bob KD5KKM is an awesome guy who has helped innumerable students at NMSU and helped me with my research project while I was there.


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Cool Math Tricks: Deriving the Divergence, (Del or Nabla) into New (Cylindrical) Coordinate Systems

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The following is a pretty lengthy procedure, but converting the divergence, (nabla, del) operator between coordinate systems comes up pretty often. While there are tables for converting between common coordinate systems, there seem to be fewer explanations of the procedure for deriving the conversion, so here goes!

What do we actually want?

To convert the Cartesian nabla

to the nabla for another coordinate system, say… cylindrical coordinates.

What we’ll need:

1. The Cartesian Nabla:

2. A set of equations relating the Cartesian coordinates to cylindrical coordinates:

3. A set of equations relating the Cartesian basis vectors to the basis vectors of the new coordinate system:

How to do it:

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The chain rule can be used to convert a differe…

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