Several detection methods tailor the performance of the instrument to meet specific measurement requirements. In general, several measurement points are calculated for each display point. The various detection methods are different ways of dealing with how measurement point data is shown at each display point. Refer to Units & Detection Menu.
Peak: This method causes the largest measurement point to be shown for each display point, and ensures that a narrow peak is not missed.
RMS/Avg: This method performs a root‑mean‑square calculation of all the measurement points in each display point. This is particularly useful in displaying the average value of noise or noise‑like signals.
Negative: This method causes the smallest measurement point to be shown for each display point. It is especially useful in zero span, to see if the signal amplitude drops briefly. The method is also useful when looking at modulated signals, to see if some frequencies are not being used.
Sample: This is the fastest detection method because for each display point, only one frequency point is measured. Use this method when speed is of paramount importance and the possibility of missing a narrow peak is not important.
Quasi‑peak: When this selection is made, resolution bandwidths and video bandwidths of 200 Hz, 9 kHz and 120 kHz are available. This detection method is designed to meet CISPR requirements. (Not available in zero span.)