NARDA PMM 9010 Series, User Manual

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PMM 9030/9060/9180 Frequency Extension 11-45
11.16.2.3.1 Input:
Attenuators
and
preamplifier Being entered in the Input submenu, to increase or decrease the attenuation
at the input, press
Att + or Att - , and for each touch the attenuation is
increased or decreased of 5 dB (preset value) up to the max attenuation
available of 55 dB.
Depressing either one of these keys force the receiver in manual attenuation.
The
Min Att button acts as a toggle switch: it selects or deselects the
minimum attenuation of 10 dB. When the minimum attenuation is selected, the
attenuator – doesn’t matter if in automatic or in manual condition - cannot be
lowered under 10 dB.
Unless specifically required by the test conditions, do not remove the
minimum attenuation of 10 dB.
With the
Preamp key it is possible to insert or exclude the built-in low noise
preamplification of 10 dB.
The internal 10 dB preamplifier can be used when very weak signals have to
be investigated. As already mentioned, with the preamplifier ON the receiver
takes automatically care of the 10 dB gain when measuring the signals.
The Preamplifier must be mandatory switched off (default) while carrying on
CISPR measurements.
The
Att Auto button is used to switch from the two conditions of manual or
automatic attenuation setting.
Please note that the switching of the attenuators is relatively noisy and you
can perceive it distinctly with a “click” for each switch operation.
11.16.2.3.2 Misc
Under the Miscellanea functions menu it is possible to activate or exclude the
Preselector filters 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 9030/9060/9180 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.
Pressing the
RF OUT button the receiver enters the Tracking generator menu.
11.16.2.3.3 Tracking
generator The Tracking generator is an internal, high stability and accuracy, 50 Ohm
RF generator ranging from 10 Hz to 50 MHz.
It is a CW signal source tuned at the frequency set under the
RF OUT Freq
window.
As usual, to set a given frequency it is therefore enough to edit the value with
the soft keys and the left an 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.
If a higher or lower level is needed, the User shall adopt either an external
amplifier or an external attenuator.
With the PMM 9030/9060/9180 the
Tracking On function is not available.