How do I get >8 bit vertical resolution on my Agilent real-time oscilloscope?
The Agilent’s real-time oscilloscope gives 8-bit vertical resolution at normal acquisition mode like most other digitizing oscilloscopes does. However, high-resolution mode on the scope offers up to 12 bits of vertical resolution in real-time mode, which reduces noise and increases vertical resolution. When operating at slow time base ranges, the oscilloscopes serially filter sequential data points and map the filtered results to the display. Increasing the memory depth of on-screen data increases the number of points averaged together. High-resolution mode has no effect at fast time/div settings, where the number of on-screen points captured is small. It has a large effect at slow time/div settings, where the number of on-screen points is low compared to the of points captured. Basically the scope is over sampling and has more acquired data points than is needed to fill the screen. The high-resolution mode just averages those extra samples together to give you better vertical resolution.