La description

Key Facts When equipped with the R&S®DDF255-PS option, the R&S®DDF255 traverses a user-defined frequency range at maximum speed (without direction finding). This provides a quick overview of the spectrum occupancy. Any changes caused by illegal radio services, interference sources, temporary emissions, etc., can thus be recognized immediately. The marker function can be used to take a bearing of, demodulate and analyze the target signal. The resolution for the FFT computation can be set to match the channel spacing used by various radio services. This FFT scan provides fast scan rates at narrow resolution bandwidths and thus high sensitivity.
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