28Measuring Multiple SignalsResolving Signals of Equal AmplitudeResolving Signals of Equal AmplitudeIn this procedure a decrease in resolution bandwidth is used in combination with adecrease in video bandwidth to resolve two signals of equal amplitude with afrequency separation of 100 kHz. Notice that the final RBW selection to resolve thesignals is the same width as the signal separation while the VBW is slightly narrowerthan the RBW.Step Action Notes1 Connect two sources to theanalyzer RF INPUT asshown.2 Set up the signal sources. a. Set the frequency of signalgenerator #1 to 300 MHz.b. Set the frequency of signalgenerator #2 to 300.1 MHz.c. Set signal generator #1 amplitudeto −20 dBm.d. Set signal generator #2 amplitudeto −4 dBm.The amplitude of both signalsshould be approximately−20 dBm at the output of thebridge/directional coupler. (The−4 dBm setting plus −16 dBcoupling factor of the 86205Aresults in a −20 dBm signal.)3 Select the mode. • Press Mode, Spectrum Analyzer.4 Preset the analyzer. • Press Mode Preset.5 Set up the analyzer to viewthe signals.a. Press FREQ Channel, CenterFreq, 300, MHz.b. Press BW, Res BW, 300, kHz.c. Press SPAN X Scale, Span, 2,MHz.A single signal peak is visible.See Figure 2-5.
