A narrow band receiver or transceiver for processing electrical signals. The narrow band receiver or transceiver includes an amplifier, a voltage controlled oscillator and a tuning assembly comprising at least one control loop for tuning of the voltage controlled oscillator. At least a gain control of the amplifier is coupled to the control loop for simultaneously tuning the output amplitude of the voltage controlled oscillator and the gain of the amplifier. A compensation of the effect of variation on the gain of the amplifier, which includes an LC tank circuit, is performed by using an information in another LC tank circuit of the voltage controlled oscillator in the control loop.