RF Test Instruments#

The instruments that make invisible signals visible.

RF measurement requires specialized equipment because the act of measuring can disturb the circuit. Probing a node at 1 GHz is not like probing one at 1 kHz β€” the probe itself becomes part of the RF network, and the measurement technique must account for this. The instruments in this section are designed for frequency-domain analysis, S-parameter measurement, and power detection at frequencies where general-purpose bench equipment falls short.

Instrument Pages#

  • Spectrum Analyzers β€” Understanding frequency-domain measurement: swept-tuned and FFT-based analyzers, key specs (RBW, dynamic range, phase noise), and what to look for on the display.

  • Vector Network Analyzers β€” Measuring magnitude and phase with S-parameters, calibration procedures, and practical uses including the NanoVNA.

  • Using Oscilloscopes at RF β€” Where time-domain instruments help at RF frequencies, and where they fall short.

  • Directional Couplers & Power Meters β€” Sampling forward and reverse power, measuring RF power levels, and understanding coupling and directivity.

For general bench instruments (oscilloscopes, DMMs, signal generators), see Test Instruments in the Measurement & Test section.

Backward SDR as a Learning Instrument Spectrum Analyzers Forward