Final answer:
Poor frequency stability in a radio receiver typically originates in the local oscillator, which is essential for tuning accuracy and stable signal reception.
Step-by-step explanation:
Poor frequency stability in a receiver usually originates in the d) Local oscillator. The local oscillator in a radio receiver is responsible for generating a stable frequency that is mixed with the incoming radio frequency (RF) signal in the mixer stage. The stability of the local oscillator is crucial as it determines the precision with which the receiver can tune to a specific frequency. If the local oscillator has poor frequency stability, the receiver may drift from the desired frequency, causing problems with receiving the intended signal.
In a radio receiver, an RLC circuit is often used to select specific frequencies. The performance of this circuit, including its frequency stability, can be influenced by factors such as component tolerances and environmental changes like temperature. The resistance, inductance, and capacitance values are chosen to achieve the desired quality of signal reception and tuning accuracy. To maintain a stable frequency, high-quality components with minimal temperature coefficients and proper circuit design are necessary.