*Question G7A12:
Which symbol in Figure G7-1 represents a solid core transformer?*  

*Correct Answer is  C: Symbol 6*  

### AI Response: (may contain errors)  

In Figure G7-1, the symbols represent different types of transformers. The correct answer is Symbol 6, which represents a solid core transformer.

### Explanation of the Correct Answer:
- **Symbol 6**: This symbol indicates a solid core transformer. Solid core transformers are typically used for their efficiency and ability to handle higher power levels without significant losses.

### Explanation of Incorrect Choices:
- **Symbol 4**: This symbol usually represents a toroidal transformer, which has a different core shape and is designed for specific applications, often with lower electromagnetic interference.
  
- **Symbol 7**: This symbol typically represents an air core transformer. Air core transformers do not have a solid core and are used in applications where low inductance is required, such as in RF circuits.

- **Symbol 1**: This symbol often represents a variable transformer or rheostat, which is not a solid core transformer but rather a device used to adjust voltage or current.

### Summary:
- **Solid Core Transformer**: Symbol 6
- **Toroidal Transformer**: Symbol 4
- **Air Core Transformer**: Symbol 7
- **Variable Transformer**: Symbol 1

Understanding these symbols is crucial for interpreting circuit diagrams and ensuring proper component selection in amateur radio projects.