Dynamic Attenuation Control
The dynamic attenuation control feature tracks the peak input signal level and automatically
adjusts the attenuator to protect the S332D in situations of high RF signal levels. This fea-
ture also enhances the instrument sensitivity in situations of low-level RF signals by deacti-
vating and activating the internal preamplifier resulting in improved measurement accuracy.
When dynamic attenuation is on, the S332D is in control of the attenuation and preamp.
Manual settings will be overwritten based on the input signal. To manually control these
parameters, set the attenuation to
Manual
.
The following is an example identifying interference in a PCS 900 MHz band with the aid
of the preamplifier and dynamic attenuation control.
Required Equipment
q
S332D Handheld Site Master
q
A PCS band Pass Filter, such as K & L Electronics 5DR30-921 or equivalent
q
A PCS band antenna
Procedure
Step 1.
If necessary, press the
MODE
key and use the Up/Down arrow key to select the
Spectrum Analyzer
mode. Press the
ENTER
key to select.
Step 2.
Reset the S332D to the factory default settings for the current mode by pressing
the
RECALL SETUP
key on the data keypad. When the key is pressed, a Re-
call Setup selection box appears on the display. Select setup location 0 <De-
fault> to recall the factory preset state for the currently selected mode.
Step 3.
Connect the PCS antenna to the input of the band pass filter, and the output of
the band pass filter to the
RF In
connector of the S332D.
Step 4.
Press the
FREQ/DIST
key.
Step 5.
Press the
Start
soft key and enter 1.93 MHz.
Step 6.
Press the
Stop
soft key and enter 1.935 MHz.
Step 7.
Press the
AMPLITUDE
key and select the
Scale
key. Set the scale to 10 dB/di-
vision.
Step 8.
Press the
Atten/Preamp
soft key and set the attenuation to
Dynamic
.
As the S332D sweeps, it continually monitors the overall input signal level and, as required,
adjusts the input attenuation value and the preamplifier on/off state to achieve the best pos-
sible sensitivity.
5-6
Chapter 5 Spectrum Analyzer Measurements