If you’ve ever dealt with RF circuits, you probably have run into Q — a dimensionless number that indicates the ratio of reactance to resistance. If you ever wanted to measure Q, you could do worse ...

While LCR meters are readily available at reasonable cost, they do not measure the Q of an inductor. This circuit enables you to measure the Q of inductors with the aid of an RF signal generator. A ...

This instrument determines the Q (quality factor) of a resonant circuit, crystal, or resonator by measuring its series resistance at the resonance frequency. The Q is linked to the series resistance ...

[Thomas] picked up a Marconi TF1245 with dents and dings. We have to admit that we had not heard of a “circuit magnification meter,” but apparently, this was a thing in the late 1960s and early 1970s.