LC oscillator calculator: Colpitts, Clapp, Hartley
Online LC oscillator calculator: frequency, feedback ratio, the condition for oscillation, and how sensitive the frequency is to the active device’s capacitance.
PLL calculator: dividers and loop filter
Online PLL synthesiser calculator: divider ratios, the loop’s natural frequency and damping, in-band phase noise and the lock time.
DDS calculator: tuning word, images and spurs
Online direct digital synthesis calculator: the frequency tuning word, the resolution, the first image frequency, the sinc roll-off and the SFDR.
VXO calculator: pulling a crystal
Online VXO calculator: the tuning range of a crystal oscillator from load capacitance, the theoretical maximum, and how a series coil extends it.