ARRL Technician Practice Exam

What is a primary factor to consider when selecting a coax cable for high-frequency applications?

1. The cable's physical size

2. The saturation level

3. The loss characteristic at high frequencies

4. The color of the outer jacket

The correct answer is: The loss characteristic at high frequencies

When selecting a coax cable for high-frequency applications, the loss characteristic at high frequencies is a primary factor to consider. This is crucial because as frequency increases, the signal loss through the cable can significantly impact performance. Loss is typically measured in decibels per 100 feet (or meter) and is influenced by the materials used in the cable, the cable's construction, and the frequency at which it operates. A cable with low loss characteristics at high frequencies will ensure that the maximum amount of the transmitted signal reaches the destination, thereby maintaining the integrity and quality of the signal. This is especially important in applications such as amateur radio, television broadcasting, and telecommunications, where high signal fidelity is essential. While the physical size of the cable, saturation levels, and outer jacket color may have their importance in specific applications or considerations, they do not have the same direct impact on signal integrity as the loss characteristics at high frequencies. Thus, focusing on minimizing loss is key for effective performance in high-frequency scenarios.