This thesis is primarily a study of noisy circuits focusing on noise in a PT-symmetric circuit introduced by the presence of the gain and loss elements. In chapter 1, we give an introduction to thermal noise and PT-symmetric electronics, providing all the calculations for the derivation of noisy circuits' signal-to-noise ratio (SNR). In chapter 2, we focused on the main calculation of noisy PT-symmetric RLC circuits in comparison with noisy non-PT-symmetric RLC circuits. Chapter 3 is devoted to the new insight of having a less noisy circuit by using a parametrically pumped LC circuit to manipulate noise.