Any type of radio frequency (RF) testing requires antennas. Equipment under test may or may not have them — some devices aren’t designed to broadcast but still might. But the analyzer will always require an antenna to receive whatever signal there might be, whether undertaking emissions, enclosure, or field testing.
In many, if not most, testing scenarios, the antenna for reception will need a preamplifier (preamp). Technicians and engineers must boost the signal to ensure adequate dynamic range for accurate and meaningful test results.
There are a number of ways that mistakes with preamps in test configurations can lead to misleading or incorrect readings or even damaged equipment and unnecessary costs. With some attention and proper equipment matching, results will be accurate and useful, and expenses will remain at a minimum.