NARDA PMM 9010 Series, User Manual

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15-12 9010F Fast
15.2.2.4 Misc
Under the Miscellanea functions menu it is possible to activate or exclude
the Preselector filters, the Pulse Limiter , and also to enter in the Tracking
generator menu pressing the RF OUT button.
The
Preselector is composed by a group of filters automatically selected by
the PMM 9010F while it is sweeping or anyway measuring. The aim of the
preselector is to reduce the amount of out-of-band energy entering in the
receiver, thus helping a lot in reducing intermodulation problems and similar
undesired behaviors.
It can be set either ON or OFF with the associated button, and normally it
should be always enabled.
On the top left corner of the screen the symbol “Off” or “On” will be
displayed.
The
Pulse Limiter is a very useful device to protect the input of the receiver
from transient overvoltages. Doing conducted emission tests, quite often
there are conducted disturbances (usually associated to switching
operations in the EUT or along the line under test) which are too high and
that propagates through the LISN up to the receiver. Sometime these
disturbances cannot be seen on the receiver because they are out of
measurement bandwidth, nevertheless the associate energy is high enough
to damage the input attenuator and/or the Analog-to-Digital Converter of the
PMM 9010F (the first mixer in a traditional receiver).
This pulse limiter has an integrated 10dB attenuator and a 30 MHz low-pass
filter.
When the Pulse Limiter is selected, on the upper part of the screen the
letters
P.L. appear next the value of the Minimum Attenuation and the
reading on the receiver is automatically corrected for the attenuation factor of
the Pulse Limiter.
Pressing the
RF OUT button the receiver enters the Tracking generator
menu.
15.2.2.5 RF Output
Generator
The RF Output generator is an internal, high stability and accuracy, 50
Ohm RF generator ranging from 10 Hz to 50 MHz.
NOTE: Due to the Ultra Fast FFT technology of the PMM 9010Fthe Tracking
function is disabled; thus the generator consists of a CW signal source tuned
at the frequency set under the
RF OUT Freq window.
As usual, to set a given frequency it is enough to edit the value with the soft
keys and the left and right arrows, confirming the selections entering the
units value (kHz, MHz or GHz).
Pressing 0 as the first figure the decimal dot appears automatically.
The output level can be set between 60,0 and 90,0 dBµV with 0,1dB steps
using the
RF OUT Level button.
The internal generator is also used for self-calibration of the PMM 9010F.
Turn Off the RF Output generator, if it is not used, while you are in
Scan Mode.
This prevents interferences and the measurements are more clean and
accurate.