*Question T7C04:
What reading on an SWR meter indicates a perfect impedance match between the antenna and the feed line?*  

*Correct Answer is  C: 1:1*  

### AI Response: (may contain errors)  

To determine the reading on an SWR (Standing Wave Ratio) meter that indicates a perfect impedance match between the antenna and the feed line, we need to understand what SWR represents.

### Correct Answer: C: 1:1

- **Why 1:1 is correct:**
  - An SWR of 1:1 indicates that the impedance of the antenna matches the impedance of the feed line perfectly (usually 50 ohms for most amateur radio systems). This means that all the power sent from the transmitter is being radiated by the antenna, with no reflected power.

### Why the other choices are incorrect:

- **A: 50:50**
  - This choice is misleading. While it suggests a perfect match, it is not the standard way to express SWR. SWR is expressed as a ratio, not as two equal values.

- **B: Zero**
  - An SWR reading of zero is not possible in practical scenarios. It would imply that there is no reflected power at all, which is unrealistic. A perfect match is indicated by 1:1, not zero.

- **D: Full Scale**
  - A full-scale reading on an SWR meter typically indicates a very high SWR, meaning there is a significant mismatch between the antenna and the feed line. This results in a lot of reflected power, which is the opposite of a perfect match.

### Useful Formula:

The SWR can be calculated using the formula:

$$
SWR = \frac{V_{max}}{V_{min}}
$$

where:
- $V_{max}$ = maximum voltage on the line
- $V_{min}$ = minimum voltage on the line

In summary, an SWR of 1:1 indicates a perfect impedance match, while the other options either misrepresent the concept or indicate poor matching conditions.