L3Harris NARDA PMM ER8000 User Manual page 30

3.2.2 ANALYZER
MODE
3.2.3 MANUAL MODE
3-2 Operating Instructions
The purpose of this operating mode is to make an easy and fast debugging
tool available to the User.
To enter the ANALYZER Mode it's enough to depress the Analyzer soft key
on the main screen.
In this mode the receiver works as a powerful Spectrum Analyzer and the
display shows the "spectrum analysis" in the frequency domain.
The analysis is done at the selected span frequency.
Using the marker facility the User can accomplish a very accurate
measurement of the signals either in frequency as well as in level.
On the screen of the Analyzer Mode all the relevant information are reported.
So that the User can see which detector is in use and the relevant hold time; if
the input attenuation is Automatic or Manual and the set attenuation and the
Minimum attenuation.
Near the graph there is the Reference level, the Resolution bandwidth and the
span value.
Below the graph the start, center and stop frequency.
A proper box is dedicated to the marker indication, with actual frequency and
level of the marker.
The MANUAL mode is a very useful feature to manually control the receiver
and to deeply investigate electrical signals modifying the parameters of
receiver exactly as per the needs of the Test Engineer.
In this operating mode, the instrument continuously display the signal level at a
desired fixed frequency (not sweeping).
It is possible, for example, to observe the signals exceeding the limits
frequency by frequency; evaluating their levels measured simultaneously with
4 different detectors (Peak, QuasiPeak, Average and RMS); listening to them
after a demodulation, etc.
To enter in Manual Mode press the key in the main menu, and immediately
the first Manual window opens.
In manual mode the levels corresponding to the detectors in use are displayed
both in analogue and in digital format, and exactly as for the other operating
modes, all the relevant information are reported on the screen.
The User can see the resolution bandwidth, the longest hold time associated
to the detectors in use; if the input attenuation is Automatic or Manual and the
set attenuation and the Minimum attenuation.
Also the Demodulator can be switched on and set to AM or FM, and the audio
volume regulated as wished and represented by a simple bar.
Then there are three or fours vertical bars representing the detectors and
indicating in analogue and digital (the figures below each bar) the level
measured; on top of the bars the relevant detector, the unit in use and the
tuned frequency. The analogue scale of the analogue bars is set automatically
by the software in accordance with the Reference Level set.
In case an OVERLOAD indication occurs it is necessary to add an
external attenuator to carry on the measurement without overpassing the
declared limit for continuous power or spectral density.
Using 0 dB attenuation PMM ER8000 has no input protection.
This is a potentially dangerous condition for the input stage of the
receiver.
Use 0 dB attenuation only if you are very sure that your input signal is
less than 0,5 Vpp (or 106 dBµV).
Before to apply an unknown signal to PMM ER8000 receiver, use an
oscilloscope or a wide band RF voltmeter to measure it. In any case set
Min. ATT at 10 dB and select the maximum available attenuation.
If needed, add an external coaxial attenuator on the input signal line.