Introduction
In a closed-loop control system, the feedback gain plays a crucial role in determining the overall gain of the system. The overall gain refers to the amplification or attenuation of the input signal by the system. The positive value of the feedback gain can have a significant impact on the overall gain of the system.

Explanation
When the feedback gain is positive, it means that the feedback signal is in phase with the input signal. This positive feedback tends to amplify the input signal and can lead to an increase in the overall gain of the system.

Positive Feedback
Positive feedback occurs when a portion of the output signal is fed back and added to the input signal. This can enhance or amplify the input signal, resulting in a higher overall gain. The positive feedback gain is denoted by the symbol β.

Feedback Gain and Overall Gain
The overall gain of a closed-loop control system is given by the product of the forward gain (G) and the feedback gain (β). Mathematically, it can be expressed as:

Overall Gain = G * β

When the feedback gain (β) is positive, an increase in β would result in an increase in the overall gain of the system. This is because the positive feedback reinforces the input signal, leading to a higher output signal.

Effect on Stability
While a positive feedback gain can increase the overall gain of the system, it can also have an impact on stability. Positive feedback can introduce instability in the system, leading to oscillations or even system failure. Therefore, it is important to carefully design the control system to ensure stability while considering the positive feedback gain.

Conclusion
In a closed-loop control system, a positive value of feedback gain can increase the overall gain of the system. This is because the positive feedback reinforces the input signal, resulting in a higher output signal. However, it is important to consider the stability of the system when using positive feedback, as it can introduce instability if not properly controlled.