Construction Coordinator Practice Exam

What must be done when measuring port-to-port isolation in a splitter or directional coupler?

1. Terminate the common input port

2. Remove the power inserter from the circuit

3. Use a spectrum analyzer

4. Disconnect all output ports

The correct answer is: Terminate the common input port

When measuring port-to-port isolation in a splitter or directional coupler, terminating the common input port is essential for ensuring accurate results. This process prevents reflections and interference that could skew the measurements. By terminating the input, you create a controlled environment where the signal is absorbed rather than reflected back into the device, which would complicate the assessment of isolation between the output ports. The isolation measurement is focused on how much unwanted signal coupling occurs between the output ports when a signal is applied to the input. Having a proper termination on the input ensures that the only signals observed at the output ports are a direct result of the coupling characteristics of the device. This helps to quantify how well the device is performing its intended function of isolating ports from each other, which is crucial in applications to prevent interference and crosstalk between paths. The other options either address different aspects of testing or do not align specifically with the requirements for measuring isolation. For example, removing the power inserter may impact the circuit but does not directly relate to the isolation measurement. Similarly, while using a spectrum analyzer and disconnecting all output ports might be relevant in some testing contexts, they do not specifically contribute to ensuring accurate port-to-port isolation measurements in this scenario. Therefore, terminating the