Table 6-1.Description of Front Panel Controls, Indicators, and ConnectorsContinued
When activated, this will increase the resolution so that each major graticule
division represents 2 dB.
When activated, this selects a linear display between zero volts (bottom graticule
line) and the reference level (top graticule line) scaled in volts/division (see
REFERENCE LEVEL, No. 23a).
When selected, this increases the fall time of the pulse signals so that very narrow
pulses in a line spectrum display can be observed.
One of two (NARROW OR WIDE) filters can be activated to reduce video
bandwidth and high-frequency components for display noise averaging. The
narrow filter is approximately 1/300th of the selected resolution bandwidth with
the wide filter being 1/30th the bandwidth. Activating either one will cancel the
other. To disable, completely switch filter off.
Five push buttons and ON control operate the digital storage functions. With none
of the push buttons activated, the display will not be stored.
VIEW A, VIEW B
When either or both of these push buttons are selected, the push button illuminates,
and the contents of memory A and/or memory B are displayed. With Save A mode
off, data in a memory is interlaced with data from B memory.
When activated, the differential (arithmetic difference) of data in B memory and
the saved data in memory A are displayed. SAVE A mode is activated and SAVE
A button will be lit.
When activated, the digital storage memory retains the maximum signal amplitude
at each memory location. This permits visual monitoring of signal frequency and
amplitude at each memory location over an indefinite period of time. This feature
is used to measure drift, stability, and record peak amplitude.
This control selects the amplitude at which the vertical display is either peak
detected or averaged. Video signals above the level set by the control (shown by a
horizontal line or cursor) are peak detected and stored while video signals below
the cursor are digitally averaged and stored.
MIN RF ATTEN
This control is used to set the minimum amount of RF attenuation. Changing RF
LEVEL will not decrease RF attenuation below that set by the MIN RF ATTEN
This is a continuous control that requests the microcomputer to change the
reference level one step for each detent. In the 10 dB/DIV vertical-display mode,
the steps are 1 dB or 0.25 dB if the FINE mode (No. 26) is selected.
MIN RF ATTEN DB
This selects the lowest value of attenuation allowed: Actual RF attenuation is set
by the microcomputer according to the logarithm selected by the MIN NOISE/MIN
DISTORTION (No. 27) button. If RF attenuation is increased by changing MIN
RF ATTEN, the microcomputer automatically changes IF gain to maintain the
current reference level.
This indicator lights when the display amplitude is no longer calibrated (selecting a
sweep rate that is not compatible with the frequency span/div and resolution
LOG and AMPL
These adjustments calibrate the dynamic range of the display. The LOG calibrates
any logarithm gain dB/Div, and the AMPL calibrates the reference level of the top
graticule line at the top of the display.
When activated, the REFERENCE LEVEL (No. 23a) switches in 1 dB increments
for 10 dB/Div display mode, 0.25 dB for 2 dB/Div, and volts 1 dB for LIN display