On the Elecraft mailing list, there’s been a flurry of messages recently about LCR meters. One of the units touted was a unit from a company called Almost All Digital Electronics. They have both a kit version ($100) and an assembled version ($130). A couple of the guys even bought and built it.

I chimed in with the opinion that instead of buying yet another meter, that they should just buy an antenna analyzer to make those measurements. My analyzer can measure inductance and capacitance directly, and do so at any frequency up to 35 MHz. It may not be quite as accurate and the LCR meter, but my guess is that it’s plenty accurate for amateur use. And to top it off, I get to use it to analyze my antennas!

I just used it to demonstate the principles of reactance and impedance to my General class students. I first measured the reactance of a coil that I’ve had around the shack for ages (at one time, I used it as a loading coil coil for a vertical antenna). I showed how the reactance increased with frequency, then recorded the reactance at 6 MHz.

Next, I measured the resistance of a 150-ohm precision resistor that came with my analyzer. Then, I calculated the impedance with the equations Z = sqrt(XL**2 + R**2).

I then connected the resistor in series with the coil and measured the impedance. Surprisingly (not so surprising, actually) the measured impedance was almost exactly what I’d calculated.

Actually, my analzyer–the Autek VA1–is not an antenna analyzer at all. It’s a Vector Analyzer. It just so happens that antennas are perfect specimens for the type of analysis that the VA1 is capable of performing.