*Question E7C03:
What is the purpose of adding an inductor to a Pi-network to create a Pi-L-network?*  

*Correct Answer is  A: Greater harmonic suppression*  

### AI Response: (may contain errors)  

To understand why adding an inductor to a Pi-network to create a Pi-L-network results in greater harmonic suppression, let's break down the purpose and function of these networks:

1. **Pi-Network**: This is a type of filter used in RF circuits, typically for impedance matching and harmonic suppression. It consists of two capacitors and an inductor arranged in the shape of the Greek letter "π".

2. **Pi-L-Network**: By adding an additional inductor to the Pi-network, you create a Pi-L-network. This configuration enhances the network's ability to suppress harmonics.

### Explanation:

- **Correct Answer: Greater harmonic suppression (A)**  
  The addition of an inductor in a Pi-L-network increases the order of the filter. This means it can more effectively attenuate unwanted harmonic frequencies, which are multiples of the fundamental frequency. The extra inductor provides additional filtering capability, making the network more effective at reducing harmonics.

### Why Other Choices Are Incorrect:

- **Higher efficiency (B)**  
  While a Pi-L-network can improve harmonic suppression, it does not inherently increase the efficiency of the circuit. Efficiency is more related to how well the network matches impedances and minimizes losses, rather than the presence of an additional inductor.

- **To eliminate one capacitor (C)**  
  Adding an inductor does not eliminate a capacitor. In fact, the Pi-L-network adds an inductor to the existing Pi-network, increasing the component count rather than reducing it.

- **Greater transformation range (D)**  
  The transformation range, or the ability to match a wide range of impedances, is primarily determined by the values of the components and their configuration. While a Pi-L-network might offer some flexibility, its primary advantage is harmonic suppression, not an increased transformation range.

### Useful Rule of Thumb:

- **Harmonic Suppression**: The more elements in a filter network, the higher the order of the filter, and the better it can suppress harmonics. Adding an inductor increases the filter's order, thus enhancing its ability to suppress higher-order harmonics.

In summary, the primary purpose of adding an inductor to create a Pi-L-network is to achieve greater harmonic suppression, making it the correct answer.