In the plot of reactance v/s frequency of a crystal oscillator, the reactance between series resonant frequency and parallel resonant frequency is:

A quartz crystals equivalent circuit is a series LCR circuit and has a series resonant frequency.

Quartz crystal and tourmaline used in oscillators work on the principle of:

In an oscillator, the resonant feedback circuit must have must have a low Q in order to achieve stable oscillation.

One condition to be satisfied in an oscillator circuit so that stable oscillations are produced is:

Expression for over all noise figure of a mismatched amplifier is:

Noise equivalent temperature of Wilkinson coupler having a gain of 1/is given as:

For a Wilkinson power divider of insertion loss L and the coupler is matched to the external circuitry, and then the gain of the coupler in terms of insertion loss is:

Noise equivalent temperature of a 2 stage cascade network is given by:

Expression for noise of a two port network considering the noise due to transmission line and other lossy components is:

Noise figure can be defined for any microwave network irrespective of any other constraints.

The equivalent noise temperature of a network given the noise figure of the network or system is:

is defined as the ratio of input signal to noise ratio to the output signal to noise ratio.

is defined as the ratio of desired signal power to undesired noise power.

Amplifier efficiency is the ratio of RF output power to DC input power. This parameter determines the performance of an amplifier.

For Colpitts oscillator, the capacitors C1 and C2 in the feedback network are 1 µF andµF respectively. Then the β value of the transistor is:

Colpitts oscillator in the feedback section has an inductance of 4 mH and capacitors ofnH and 4 nH. Then the resonant frequency of Colpitts oscillator is:

Hartley oscillator has inductance values ofmH and 4 mH in the feedback section and a capacitor of 4 nF. Then the resonant frequency of the circuit is:

An inductor is operating at frequency ofMHz. Its inductance is 0.1 µH, and then the series resistance associated with the inductor is: (Qo=100)

Colpitts oscillator operating atMHz has an inductor in the feedback section of value 0.10µH. then the values of the capacitors in the feedback section is: