Designers have exploited many circuit topologies—some highly complex—in their attempts to achieve these design goals, but certain active devices' basic properties can help designers obtain acceptable ...

It would be an LC oscillator whose frequency is changed by the variable capacitance of one or more varactors. A digital method of modulating a PLL is to rapidly change the divider value.

With the circuit shown, values of C1 and C2 should be chosen so that the maximum LC oscillator frequency is about 500 kHz. Frequency measurements are made for 32.5 ms.

Glen Chenier’s blog I reposted yesterday got me thinking about other LC measurement techniques, including an inductance checker I built about 40 years ago and haven't used in nearly as long. The ...