Applied Instruments NPRT 2200 User manual

Operation Manual NPRT 2200
NPRT 2200
Operation Manual
Module Version
NPRT 2200 4.05
NprGraph 2.11
SwpEditor 2.00
12 02 2016

Operation Manual NPRT 2200
Table of Contents
1. Introduction.............................................................................................................1
1.1. NPR Measurement..........................................................................................1
1.2. NPRT Block Diagram......................................................................................1
1.3. Power Sweep Graph.......................................................................................2
2. Installation and Setup.............................................................................................3
2.1. Connections.....................................................................................................3
2.2. Warm-up..........................................................................................................3
2.3. Software Installation........................................................................................3
3. Front Panel Operations..........................................................................................4
3.1. Main Menu.......................................................................................................4
3.2. User Calibration...............................................................................................5
3.3. Manual Operations..........................................................................................6
3.4. NPR Test.........................................................................................................6
3.5. Setup...............................................................................................................7
3.6. Remote Screen................................................................................................7
4. Diagnostic Screens................................................................................................8
4.1. NS-3 Diagnostic Screen..................................................................................8
4.2. Filter Board Diagnostics..................................................................................9
4.3. Receiver Diagnostics.......................................................................................9
4.4. Switch Diagnostics........................................................................................10
5. Computer Controlled Operation...........................................................................11
5.1. Setup Files.....................................................................................................11
5.2. Setup File Parameters...................................................................................11
5.3. SwpEditor screen..........................................................................................12
5.4. Starting NprGraph program...........................................................................12
5.5. Power Sweep.................................................................................................13
5.6. Power Sweep Graph.....................................................................................14
5.7. File Menu Options.........................................................................................15
5.8. Adding Lines..................................................................................................15
5.9. Edit Menu Options.........................................................................................16
5.10. NPRT Menu Options...................................................................................18
5.11. Batch Operation...........................................................................................18
6. Remote Commands.............................................................................................20
6.1. Cable and Handshaking................................................................................20
6.2. Commands....................................................................................................20
6.3. Error Reporting..............................................................................................23
6.4. SCPI Required Commands...........................................................................23
6.5. Multiple Commands.......................................................................................24
6.6. Multiple Port Usage.......................................................................................24
7. Upgrading Firmware.............................................................................................25

Operation Manual NPRT 2200
1. Introduction
The Noise Power Ratio quantifies performance degradation in active RF components, primarily
inter-modulation distortion.
The Applied Instruments Model NPRT 2200 Noise Power Ratio Test Set performs this test for
cable return band components and other equipment that operates in one of the available
frequency ranges. Many frequency bands are available from 5 to 42 MHz up to 5 to 300 MHz.
The NPRT 2200 operates as a stand-alone device or in conjunction with a PC application
software package. The NprGraph Windows software is provided with the instrument.
1.1. NPR Measurement
The Noise Power Ratio test compares the power of a carrier signal to the power of the noise
generated by signal distortions. The technique uses a deep notch filter to remove a portion of the
carrier signal in a very narrow frequency band where the noise power is measured. Then carrier
power is measured at the same frequency with the notch filter removed.
1.2. NPRT Block Dia ram
The NPRT 2200 consists of a calibrated signal source that generates a noise signal with a
precise power level. This signal is used as the input stimulus to a Device Under Test (DUT). The
DUT may be any active RF component that operates in the frequency band of the instrument.
The output from the DUT is measured by the receiver portion of the NPRT 2200, with and without
the notch filter inserted into the input signal, and the NPR is calculated.
Signal Source ReceiverDUT
Page 1

Operation Manual NPRT 2200
1.3. Power Sweep Graph
In a Power Sweep test, the NPR is measured for a sequence of input power levels. Using a PC,
this data can be plotted to characterize the performance of the DUT across its input power range.
The graph includes a horizontal line at a specified NPR limit and calculates the points where the
curve crosses the line. The difference between these two points is the usable dynamic range of
the DUT and is compared to required range limit to determine a PASS FAIL grade for the test.
Page 2

Operation Manual NPRT 2200
2. Installation and Setup
2.1. Connections
1) Connect the NPRT 2200 “Noise Output” port to the device under test (DUT) RF input port.
2) Connect the DUT RF output to the NPRT 2200 “Receiver Input” port.
3) Connect your PC using either:
a) PC serial port to the NPRT 2200 serial port on the back panel with the provided cable (or
a standard straight-thru serial cable).
b) PC USB port to NPRT USB port on back panel (USB Type A to B standard cable)
Note: Instruments built prior to 7 10 2014 do not support the USB cable connection even though a
USB port is present on the back panel.
2.2. Warm-up
The instrument is temperature compensated to maintain accuracy over normal room
temperatures but a short warm-up period of 5 minutes after power up is recommended.
2.3. Software Installation
The software provided with the NPRT is designed to run under the Microsoft Windows XP,
Vista, 7 or 8 operating systems. The software is provided on CD or may be downloaded from our
website:
www.appliedin.com downloads nprtsetup.exe
Run (or open or double click) the file to unzip the files onto your PC’s hard drive. You will be
asked to select your operating system for the installation of drivers and shortcuts.
If you are NOT asked to select an operating system, but only the file Unzip window shows, then
using Windows Explorer or My Computer , navigate to the C:\Applied\ folder where the files were
unzipped and double click setup.bat. This should continue the installation.
Folders
By default, the installation will create the following folders:
C:\Applied\ for program files
C:\Applied\Plans\ for setup files
C:\Applied\Data\ for saving data files
Desktop Icons
Shortcut icons will be placed on your Windows desktop to start the NprGraph.exe and
SwpEditor.exe programs.
USB Port Driver
The USB port driver should be installed by the installation program above. However, if Windows
does not recognize the driver when you connect the instrument, the Windows new hardware
installation wizard should be directed to load the drivers from the CD or from the C:\Applied\
folder.
Page 3

Operation Manual NPRT 2200
3. Front Panel Operations
The NPRT 2200 stand-alone operations are limited to single point NPR testing, source controls,
calibration and diagnostics. Stand-alone power sweep tests may be available in a future version.
Power Sweep tests are available with this version using the supplied PC software.
The manual control screen lets you select which frequency range, and notch filter to use, if more
than one are provided. It also lets you switch the notch in and out and set any desired output
power level. Finally, it displays the measured input power.
In a single point manual NPR test, you enter the desired power level and the instrument
measures and displays the corresponding Noise Power Ratio.
3.1. Main Menu
The first screen shown after power-up is the main menu. There are two main menu screens:
Press MORE to display the second menu screen:
The menu options are:
1) NPR – make NPR measurements at a selected power levels
2) Manual – Set source output controls and measure received power
3) Cal – Cable calibration procedure
4) Setup – change screen contrast and options
5) Diag – diagnostic screens
You may select an option by pressing the “soft key” directly under the menu option.
Page 4
Main Menu
NPR Manual Cal MORE
Main Menu
Setup Diag MORE

Operation Manual NPRT 2200
3.2. User Calibration
The instrument is temperature compensated and calibrated at the factory to maintain accuracy
over normal operating conditions. The calibration screen allows offsetting the measurements to
allow for cable and connector loss between the instrument and the DUT. This procedure requires
an external power meter capable of measuring a level of +5 dBm.
Use of the calibration screen is NOT required.
These calibration offsets can be turned on or off in the setup screen.
There is one source offset for each frequency band. There are two receiver offsets for each band
and notch combination, one for the high power level readings and one for low power level
readings.
When the CAL button is pressed, the following screen appears. From this screen you can
manually enter the offsets, or can use a more automated procedure by pressing the TX+RX or
the TX soft-keys. Use of the automated procedures is recommended.
Manual Entry
To enter the offsets manually, note which band is displayed at the top of the screen and enter the
offset for that band. When you press ENTER the next band and offset will appear. You can
press NEXT to skip entry of an offset.
After all source (Tx) offsets are entered, the receiver offsets will begin. The first offset for each
combination is used with the higher power readings (about -25 dBm or higher). The second is for
lower power readings. Enter the desired offset or press NEXT to skip.
Page 5
CABLE Band: 5:42 MHz
CALIBRATION T offset: -0.00
EXIT TX+RX RX NEXT
CABLE Band: 5:42 MHz
CALIBRATION Notch: 21.4 MHz
R offset 1: 0.00
EXIT TX+RX RX NEXT

Operation Manual NPRT 2200
Automatic TX Entry
The automated procedure for the transmit side requires an external power meter. Connect the
power meter to the end of the source cable, enter the power meter reading, and press NEXT.
You will be prompted to enter a reading for each frequency band.
When the TX side is done, the RX side calibration is started.
Automatic RX Entry
This portion of the procedure uses the now calibrated output level to compare to the measured
input level and calculate a correction offset. This is done for both attenuator ranges within the
receiver and for all combinations of band and notch.
Just connect the end of the output cable to the end of the input cable with a barrel connector and
press NEXT. The procedure takes a little while to run through all combinations. The display is
updated as each combination is tested.
When complete, the initial calibration screen is displayed again.
To activate the calibration offsets, go to the SETUP screen and set the User Cal option ON.
Page 6
CALIBRATION Band: 5:42 MHz
Connect Power Meter to output cable.
Enter power meter reading: 0.00 dBm
EXIT NEXT
RX CAL
Connect r input cable to output cable.
EXIT NEXT
RX CAL 5:42 MHz 41.0 MHz
Levels -10.12 -35.52
Offset 0.48 0.20
EXIT Testing...

Operation Manual NPRT 2200
3.3. Manual Operations
Press “Manual” from the main menu to display the following screen, which can be used to set
individual source controls and display the measured power:
This screen has five fields where you can position the cursor and change values. The Source
field is a numeric entry field and the others are multiple choice fields. For the multiple choice
fields you may press ENTER to go to the next choice for that field or may use the digit keys.
Note: the ranges and notch filters available on this screen will depend on the options installed in
your instruments.
Range:
Press ENTER to change the frequency range between 5-42, 5-65 and 5-200 MHz.
Or press “1” to select 5-42, “2” to select 5-65 or “3” to select 5-200.
Notch:
Press ENTER to change the notch filter between 21.4 and 30.5 MHz.
Or press “1” to select 21.4 or “2” to select 30.5.
In Out:
Press ENTER to switch between the notch-in and notch-out conditions.
Or press “0” to select notch out or “1” to select notch in.
Power:
Press ENTER to switch the RF power on or off.
Or press “0” to turn RF power off or “1” to turn RF power on.
Source:
Enter the desired source output power level.
3.4. NPR Test
The “NPR” menu option may be used to perform individual NPR measurements at specified
power levels. To perform a manual NPR test:
1) Enter the desired power level.
2) Press ENTER
Before the ENTER key is pressed and after each measurement is complete, a cursor will appear
in the power level field to accept entry of the desired power level. Enter the power level using the
numeric keypad and press ENTER. Or press the START soft-key to begin the test using the
displayed power.
Page 7
MANUAL Range: 5:42 Power: Off
Notch: 21.4 Source: -50.00
In/Out: Out Receiver: UNDER
EXIT (ENTER changes options)
Manual NPR Input -10.00 dBm
Enter Input Power Output __.__ dBm
Noise __.__ dBm
START EXIT NPR __.__ dB

Operation Manual NPRT 2200
When the test is complete the measured output power, noise power and NPR will be displayed:
3.5. Setup
The SETUP menu option displays the following screen:
The contrast level may be adjusted by changing the contrast number. A higher number will make
the screen darker.
The Temp Comp field may be used to disable the temperature compensation. Press ENTER to
select either on or off. Highly Recommended: keep this ON.
The User Cal field may be used to disable the calibration offsets entered on the calibration
screen. Press ENTER to select either on or off.
The Avg Limit field defines the number of samples that are averaged per reading. A value of 10
provides very reliable readings. A value as small as 4 will still provide acceptable readings and
will run faster.
Note: there are two additional setup parameters which do not appear on this screen and can only
be changed via the remote serial port. These are the settling time delay in milliseconds and the
power units used in remote commands. See the Remote Commands section.
The PRESET button will initialize the flash memory used to hold these parameters and reset
them all to their default values.
3.6. Remote Screen
When the device is being controlled from the computer, the following screen will be visible on the
NPR 2200 display.
Page 8
SETUP Contrast 25
Temp Comp On
User Cal Off
EXIT PRESET Avg Limit 10
Remote 5:42 21.4 MHz Input:-10.0 dBm
waiting Output: 2.1 dBm
Noise:-45.3 dBm
EXIT NPR: 47.4 dB
Manual NPR Input 10.0 dBm
Enter Input Power Output 26.6 dBm
Noise-32.4 dBm
START EXIT NPR 59.0 dB

Operation Manual NPRT 2200
4. Dia nostic Screens
The diagnostic screens are intended for use in diagnosing possible problems with the instrument.
These screens are not intended for use in normal operations.
There are 3 screens, organized under a diagnostic menu screen around 3 major subsections of
the device.
4.1. NS-3 Dia nostic Screen
This screen contains the diagnostics for the NS-3 noise source module that provides the base
noise signal.
You may specify the step number and DAC value for the NS-3 attenuators; the screen then
displays the calibrated dB levels for those settings plus the base calibration value and calculates
the resulting output power.
You may also specify the desired output level and the screen will calculate the required step and
DAC settings.
Note that the NS-3 module output is connected to the filter and notch switching board before
being routed to the “Noise Output” port. The “Output” level set on the NS-3 screen will only
appear on the Noise Output port if the range attenuators are set to 0 and the notch filter is
switched out.
Page 9
NS-3 Diag Base: 12.18
32.5 Deg C Step: 1 NS-3: -1.10
DAC: 203 Path: -0.85
EXIT Output: 10.23
Diagnostics
NS-3 Filter R er MORE
Diagnostics
T Sw R Sw EXIT

Operation Manual NPRT 2200
4.2. Filter Board Dia nostics
This screen contains the diagnostics pertaining to the filter board.
You may specify:
1) The frequency range selection:
a) 1 = 5:42 MHz
b) 2 = 5:65 MHz
c) 3 = 5:200 MHz
2) attenuator setting
a) 0 = none
b) 1 = 15 dB pad
c) 2 = 30 dB
d) 3 = 45 dB
3) The notch filter switch setting
a) 0 = no notch
b) 1 = 21.4 MHz
c) 2 = 30.5 MHz
d) 3 = no notch available
4) The final output level
If you specify the range, attenuator and the notch settings, the screen will calculate the final
output power level. If you specify the notch and the final output level, the system will calculate
the other values.
4.3. Receiver Dia nostics
This screen contains diagnostics pertaining to the receiver board.
You may specify:
1) The source power (input to DUT)
2) The receiver crystal filter selection:
a) 1 = 21.4 MHz
b) 2 = 30.5 MHz
c) 3 = none
3) The receiver board attenuator setting
a) 0 = none
b) 1 = 15 dB pad applied
4) The notch filter switch setting
Page 10
Filter Diag Range:1 Base: 10.36
32.5 Deg C Atten:3 NS-3:-27.08
0.02 Notch:0 Path:-43.48
EXIT Output:-60.20
R er Diag Filter: 1 Src:-60.00 dBm
32.5 Deg C Atten: 1 ADC: 12100
Notch: 1 Pwr: UNDER
EXIT

Operation Manual NPRT 2200
a) 0 = no notch
b) 1 = 21.4 MHz
c) 2 = 30.5 MHz
d) 3 = not available
The system will display:
1) The temperature of the receiver
2) The measured A D counts
3) The calibrated receiver measurement
4.4. Switch Dia nostics
The remaining two diagnostic screens, “Tx Sw” and “Rx Sw” contain controls for toggling
individual switches on the RF boards. These are intended for troubleshooting use only and are
not documented here.
Page 11

Operation Manual NPRT 2200
5. Computer Controlled Operation
The following Windows applications programs are available for use with the NPRT 2200:
1) NprGraph – provides a power sweeping function and graphs the results.
2) SwpEditor – edits the setup files that define the sweep function for NprGraph.
See Section 2.3 Software Installation for instructions on installing the software to your PC.
5.1. Setup Files
Sweeping is controlled by a setup file that you can select when running the NprGraph program.
The sweep setup files may be edited using the SwpEditor program.
The following icon should be placed on your desktop by the installation program. Or, you can
start the program by opening the C:\Applied\SwpEditor.exe file.
SwpEditor.lnk
5.2. Setup File Parameters
Each sweep setup file defines parameters that control the appearance of the graph and contains
a list of step definitions that control the values used in the power sweep. The parameters are:
1) Test Name - the test setup name is displayed in the drop down selection box when selecting
a setup to use and appears on the printed graph as the “Test Name”.
2) Input Power Units – select the display units from dBm, dBmV, dBuV or dBmV Hz
3) Graph Axes
a) Y Axis Ran e
i) Min – provides the minimum NPR value for the Y axis
ii) Max – provides the maximum NPR value for the Y axis
b) X Axis Ran e
i) If Auto-scale is checked, the X axis will be scaled from the min and max step values.
ii) Min – if Auto-scale is NOT checked, defines the left end of the X axis.
iii) Max – if Auto-scale is NOT checked, defines the right end of the X axis.
4) Default Freq Ran e – selects the frequency range to use (if more than one is installed)
5) Default Notch Freq – selects the notch frequency to use (if more than one is installed)
6) Performance Specifications
a) Acceptable NPR - If non-zero, this number is used as a minimum acceptable NPR
specification. A horizontal line is drawn on the graph at this point. The first and last
points above this line are identified as the “Min Passing” input and “Max Passing’ input
points. Vertical lines are drawn at each of these points.
b) Passin dynamic ran e – The dynamic range is calculated as the difference between
the two vertical lines. If the dynamic range is greater than or equal to this limit, a PASS
grade is reported.
Page 12

Operation Manual NPRT 2200
5.3. SwpEditor screen
The table defines the steps used in the power sweep. The NprGraph program will process each
segment definition line in turn by starting at the minimum power level, and repeatedly adding the
step increment until the maximum level is reached. An NPR measurement is made at each step.
A sample setup file is included in the installation that can be edited for your purposes.
5.4. Startin NprGraph pro ram
To start the NprGraph program, double click the icon that should have been installed on your
desktop or run the program installed as C:\Applied\NprGraph.exe.
NprGraph.lnk
The program will start up and display a Power Sweep dialog box.
Page 13

Operation Manual NPRT 2200
5.5. Power Sweep
To run a test, select the setup file you want from the drop down menu. The frequency range and
notch frequency will default to the selections made in the setup file but you may change them if
desired. Enter any desired header information and then press START.
If you simply want to view an existing file, press Cancel and use the File menu to open the file.
The header information is optional and is stored in the data file and printed on the reports. You
may enter this information on this screen before starting the test, or may add it later with the
Header Information screen described below.
As the test is running, the progress will be shown in terms of segments and steps and the
measurements will be displayed as they are obtained. At the same time, the graph will be drawn
on the window behind the Power Sweep dialog box.
When the test is complete, a File Save dialog will appear that uses the serial number as the
default file name.
Page 14

Operation Manual NPRT 2200
5.6. Power Sweep Graph
At this point, the graph is complete and the pop-up dialogs are removed. You can now view and
print the graph.
The graph plots measured NPR by Input Power. The data points are shown as dots connected
by green lines. The header information is printed below the graph. The maximum NPR and the
input power that produced the maximum are listed.
If an “Acceptable NPR” specification limit is entered either in the sweep setup file or in the Graph
Setup dialog discussed in section 4.7, a horizontal blue line is drawn at that limit and vertical blue
lines are placed on the first and last point that fall above the line. The input power values where
the NPR curve crosses the limit line are calculated and listed as the Min Passing and Max
Passing points. The difference between these points is listed as the dynamic range.
Page 15

Operation Manual NPRT 2200
If a “passing dynamic range” limit is entered, a PASS or FAIL grade is reported indicating if the
dynamic range meets the limit.
5.7. File Menu Options
The usual file menu options are available:
File New – to start a new graph and access the Power Sweep dialog
File Open – to open a previously saved graph
File Close – to close the displayed graph
File Save – to save the graph after making changes (see below)
File Save As – to save the graph under a new name
Add Line – to add a previously saved file to the present graph
File Print – to print the graph
5.8. Addin Lines
Data from multiple tests can be overlaid on the same graph for comparison purposes. Select
“Add Line” from the File menu and then pick a file to add to the presently displayed graph. Added
lines will be drawn in different colors and a color legend will be added to the bottom of the report.
The header “notes” are printed in the legend, to the right of the color bar.
Page 16

Operation Manual NPRT 2200
5.9. Edit Menu Options
The Edit sub-menu provides the following functions:
Copy Copies the graph to the clipboard.
Header Info To edit the header information first entered at the end of the test.
Graph Setup To change the graph limits.
Sweep Editor Starts up the Sweep Editor program.
Copy
The copy function may be used to copy the graph image to a word processing or spreadsheet
application. This makes it simple to include graphs into reports. The image does not include the
title bar. The Control-C shortcut is also supported.
Header Information
The information contained on this screen may be entered before the test is started, or after by
using the NPRT, Edit Header Info menu option. You should save the file after changing this
information.
Page 17

Operation Manual NPRT 2200
Graph Setup
The graph appearance may be altered using this dialog.
Note: this dialog box is also a ailable by right clicking on the graph.
You may change the limits used for the X and Y axis.
You may enter an acceptable NPR limit values that places a horizontal line on the graph.
You may enter a passing dynamic range value to obtain a PASS FAIL grade for the test.
You may select which units to display the power values in.
You may also view the data as a table or a graph by changing the view selection.
The changes you make to this dialog do not take effect until you press “Apply” or “OK”. OK
closes the dialog while Apply will make the changes to the view behind the dialog box.
Page 18