The display mode in which
vertical deflection on the display is directly
proportional to the voltage of the input
signal. The bottom line of the graticule
represents 0 V, and the top line, the reference
level, some nonzero value that depends
upon the particular spectrum analyzer. On
most modern analyzers, we select the reference
level, and the scale factor becomes the
reference level value divided by the number
of graticule divisions. Although the display
is linear, modern analyzers allow reference
level and marker values to be indicated in
dBm, dBmV, dBuV, and in some cases, watts
as well as volt