Updated Jan 29, 2017, Software
Version
118 Updated Feb 24, 2014,
Update description of Primary Axis choice. Created
Dec 16, 2009, Software Version
115
This page will describe the Control
and Operation of the MSA. Most of
the controls are
described while the MSA is in the Spectrum Analyzer Mode and are common
to all
MSA Build Levels and Modes.
Specialized controls for MSA Functions will be further described
on their respective Function pages.
All MSA Functions can be accessed
from the Main MSA Page.
The MSA Graph Window
Control during Spectrum Analyzer Mode (with or without
Tracking Generator)
Control during Scalar Network Analyzer - Transmission
Mode
Control during VNA
- Transmission
Mode
Control during VNA
- Reflection Mode
(Descriptions within each Mode)
Graph Display
Indicators
Boxes and Buttons
The
Sweep Parameters Window
The
Axis Windows
Menu Items
The MSA Graph Window
The Graph
Window is the operator's interface to the MSA. It has three main areas, the top
Menu
Items, the center Graph Display and the bottom Control Panel. The
Menu Items
are for general interface and selecting Modes of operation. The
Graph Display
contains the trace, axis, marker information, and configuration
settings. The Control
Panel contains the Buttons and Boxes to control the
MSA. I expect
the Graph Window to change often, as the MSA project continues. The Graph Window has been
formatted for an 800 pixel
by 600 pixel monitor. However, it can be "re-sized" by "mouse
grabbing"
a corner (or side) to expand or contract.
Control during
Spectrum Analyzer Mode (or with Tracking Generator)
When the MSA
Program "spectrumanalyzer" is run, the MSA will
automatically begin sweeping in the default Mode of: Spectrum Analyzer
(with Signal Generator). The following is a screen print of
this mode. No signal is input to the MSA. The
Center Frequency is 0 Hz. This
is the initial default configuration, "the self-test", for the MSA. Graph Display while sweeping in
Spectrum Analyzer Mode:
The
lower right Button, labeled "Running", indicates that the MSA is
sweeping. To Halt
the sweep, position the Mouse cursor over
any of
the three Buttons, "Halt", "Halt At End", or "Running", and "Left
Click" the Mouse. The sweep
will stop and the MSA will enter the
"Halted" mode. Graph
Display when
Halted:
The buttons will change
names. While Halted, there is no
obvious activity on the display. But,
the software is continually running in the background. It
is waiting for the user to exercise an option.
The operator
will normally change the operating parameters when the sweep is
Halted, but some can be changed while actively
sweeping. If the program ever hangs up and won't respond, use the
standard "Ctrl/Alt/Del" for Windoze, and close the program. Be aware that the MSA software
program,
like
any other program, can create conflicts inside your computer while
other
programs are running. "Other programs" include, moving your
Mouse,
having a Mouse connected to the computer via USB, wireless
devices, an Internet Browser, just to name a few. As an example,
I have an external USB wireless adapter on my computer. Even though the
adapter is not active during MSA operation, the sweep speed is reduced
by 20% because the wireless program is running in the computer's
"background". By closing the wireless program in the Task Manager with
the CtrlAltDel, the MSA speed returns to normal.
To normally exit the MSA program, Halt the sweep, then, put the
mouse pointer over the X button in the upper right corner of the Graph
Window, and left click. The Graph
Window will close (disappear). The program will completely close,
ending the MSA "session".
Indicators
A small arrow below the graph's baseline indicates
where the sweep has halted. It also indicates the direction of
the sweep. The text directly below the Graph's baseline is the
Frequency, in MHz.
A "Marker" Table in the lower
left,
under the Graph, displays the
Frequency and Data measurements of any markers that have been
selected.
The text in the upper right is the current
configuration settings.
Text above either the Left or Right vertical axis
indicate the type of quantified data, with the values displayed next to
the axis scale. Message
box. This is an area between the Graph and Marker Table,
normally invisible. This box displays any messages that are
created within
the program. If an error message is displayed, the system will
automatically halt. The error
must be corrected before continuing. "Date; Time" text. This is an area above
the center of the Graph.
It displays the date and time. You can double click this area to
open a "Title" window and insert any three lines of text you
desire. This is useful for displaying information you would like
to be printed with the Graph. You can over-write the date;time
stamp, but it will return on the next "Restart".
Boxes and Buttons
"Continue" button. This will allow the Spectrum Analyzer
to continue sweeping from the point at which it was halted. In
some cases, the button will not be accessable, only a "Restart" is
allowed. During sweeping this button will change its name to "Halt". When it is clicked,
the sweep will halt immediately. "Restart" button.
This will cause the Spectrum Analyzer to restart the sweep on the first
step. A short period of time will occur before sweeping actually
begins. During this time the MSA is going through a
re-initialization and is calculating all of the points for the next
sweep. During sweeping this button will
change its name to "Runnning".
When it is clicked, the sweep will halt immediately.
Note: Pushing the keyboard's
"Alt" key will interrupt the sweep and the MSA program. Pushing the "Alt" key again
will return to sweeping. "Step
Right"
button. This will advance the Spectrum Analyzer measurement from
the last point where it was Halted, to the right,
by one step. Each click on this button will step the
frequency once and automatically Halt. When "Continue" is clicked, the sweep will
resume in the left to right direction. During normal sweeping this button
will change its name to "Halt At End".
When it is clicked, the sweep will halt at the end of the sweep. "Step
Left"
button. This will advance the Spectrum Analyzer measurement from
the last point where it was Halted, to the left,
by one step. Each click on this button will step the
frequency once and automatically Halt. When "Continue" is clicked, the sweep will
resume in the right to left direction. "Redraw" button. It is
possible that the graph may suffer a loss of information if it is
obscured by another window. If so, the Graph and its data can be
"Redrawn" with this button. "Marker" pull-down box.
This will select a labeled marker to be installed into the Graph.
The procedure is to select a marker in this box, then move the mouse
pointer over the trace where you want the marker. Double click
the left mouse button. If
"None" had been selected, the "L" marker will be installed into the
Graph as the default marker and "L" will be inserted into the "Marker"
selection box. A
marker will be placed on the data point, closest to the mouse
pointer. The values of the data point will be displayed in the
Marker Table. "Delete" button.
This will delete the selected marker from both the Graph and the Marker
Table. "Clear Marks"
button. This will delete all of the markers from both the Graph and the Marker
Table. The Marker Table will disappear, but will return after the
next "Restart" and "Halt". "MHz" box.
This will display the frequency at which the selected marker is
positioned on the Graph. You may insert any frequency, within
the range of the span, into the "MHz" box, and click the "Enter"
box. The selected marker will move to that position on the
Graph. If the inserted frequency is between two valid data
points, the marker position and its displayed data will be an
interpolation between the two valid points. Clicking the "+" or "-" buttons will move
the selected marker to the next closest valid data point, one step at a
time. "Mark->Cent"
button. This will change the Center Frequency to be the
frequency of the selected marker. It will take effect upon
clicking the "Restart" button. "Expand L-R" button. This
will change
the span of the Sweep to be between the "L" and "R" markers. It
will
take
effect upon clicking the "Restart"
button. The "L" marker can be on the right side of the "R" marker. "Test Setups"
button.
Clicking this button will open a window and allow the user to save or
access up to 10 test configurations. They will be stored as text
files in the MSA Software folder and are available for all future
sessions. Each saved configuration will include the active
preferences and calibration data. The
Sweep Parameters Windows
While Halted, position the mouse
cursor in the area just below the Graph's horizontal baseline and
double left
click. The Sweep Parameters Window
will open. It contains the buttons and boxes used to control
the parameters of the Spectrum Analyzer. You may also double
click in
the text area of the displayed parameters in the upper right to open
the Sweep
Parameters Window.
Sweep
Parameters Window for Spectrum Analyzer Mode
"Select Final Filter Path:"
drop-down box. A selection here will tell the program which
Final Xtal
Filter Path is used.
It
will send signals to an optional Bank of four Switched Filters.
These filters determine the
Resolution Bandwidth of the MSA. Path 1 is the Default
path. When selecting a different
filter path, the "Restart" must be
clicked for the system to be accurate. The software will use a
specific table of path correction values for each Path, to compensate
for MSA inaccuracies. "P1" denotes Path 1, the "10.694785"
denotes the Final I.F. frequency, and the "4" denotes the filter path
has a 4 KHz bandwidth. The software will occomodate up to 40 filters
and their calibration files. However, if a selected filter has a
designation of P5 or greater, the command to the Filter Bank will be
"Path 4". "Video Filter BW"
drop-down box. You must "tell" the sofware the position
of the Video Bandwidth Selector Switch. The 3 positions are Wide,
Mid, Narrow, and XNarrow. Commands are sent to an optional
Video Filter Module. "Graph Appearance". This
is a choice of background color for the Graph Window. "Refresh Screen Each Scan" check box.
Click box to check or uncheck. When checked, the Graph will
refresh itself on the end of each sweep. If the box is unchecked,
the Graph will not be refreshed until the sweep is Halted. This
is a user preference. For maximum sweep speed, uncheck the box. "Display Sweep Time" check box.
Click
box to check or uncheck. When checked, the sweep time, in
seconds, is
displayed in the Message Box during the sweep. This is just a speed
performance test and does not affect any other functions. "Spur Test" check box. Click box to check or
uncheck. When checked, it is a method to verify if a
signal on
the Graph is a real input signal or a spur that is created by the
Spectrum Analyzer. The Spur Test will activate
when clicking
the "OK" and "Restart" buttons. This test will change the
Phase
Detector Frequency of PLL 1. If a questionable
signal on the
graph changes location or goes away when the sweep is resumed, it means
the signal is a spur that is self-generated within the MSA. It is
not a real signal entering the input of the MSA. To return to
Normal operation, remove the check from the "Spur Test" check
box. Then click "OK" and "Restart". This button is
not used, nor displayed in the VNA Mode. "Cent" box. This is the box to
enter the Center Frequency of the sweep. Enter the frequency in
MHz. 25.0 MHz can be
entered as "25"; the decimal and zero's are not necessary. 25.200
MHz would
be entered as "25.2" ; 455 KHz, ".455" ; 1 Hz,
".000001". And, yes, "0" is a valid center frequency. "Span" box. This is the box to enter the Sweep Width. Enter the
range in MHz, with the same consideration for
decimals and zeros as in the "Cent" box. Here again, "0" is
a valid sweep width. Use "0" when you want the MSA to "zero
sweep" at
a
fixed center frequency, while displaying the signal's activity.
The terms "span" and "sweep width" have the same meaning. "Start" box. When the
Start Stop box is checked, the "Start" box will accept a value that
represents a start frequency. "Stop" box. When the Start Stop box is
checked, the "Stop" box will accept a value that represents a stop
frequency. "Steps/Sweep" box.
Enter the number of steps to compose a
single sweep. Valid numbers are from 1 to 40000. Personally, I like 400
steps, and this is the default. Use an even number to
assure that the center of the
graph is the actual center frequency of the sweep. Using a number that is a
submultiple of the Sweep Width will assure a "whole"
number being displayed for each
sweep step.
Sweeping begins at step number 0 and ends
on the step
number entered into the "Steps/Sweep" box. The number of data
measurement points will be the value of "steps" plus 1, because data
point
number "0"
is included. Example: entering the value of "2" will result in
three data points and two full steps, stepping from point number 0 to
point number
1, then point number 1 to point number 2. Point numbers and step
numbers are treated as the same value (step 135 = data point
135). Increasing the number of steps
increases the time
it will take for the MSA to complete a full sweep. "Wait
(ms)" box. As this
value
is increased, the sweep
is slowed and the measured data becomes more precise. As a
general
rule of thumb, if the Video Bandwidth Selection Switch is selected for
Wide bandwidth, then enter 0 or 1 for fastest
response with minor data error. For Medium video bandwidth ,
enter 1 to 10. For Narrow bandwidth, enter 10 to 500.
Higher values are fine. The amount of real time for
each
whole
number increment is approximately 1 millisecond for each whole number. The value of "0" will
remove all
delay and allow maximum sweep speed. Values above "15" will be
rounded off to increments of 10 in the software. You may resume
sweeping without
having to use "Restart". The higher the value, the longer
it will take for the MSA to complete a full sweep.
Special Note on Sweep Speed:
Sweep speed is also affected by some of the other
parameters. For maximum sweep speed, uncheck the "Refresh Screen
Each Scan" and "Display Sweep Time" boxes. Enter "0" into the "Wait (ms)" box. Decrease
the number of data points taken, the "Steps/Sweep" box. Use the
minimum needed to display a viable trace. Trial and error will
give the user best results.
It must be
noted that sweep speed affects the quality and accuracy of the
data. It takes a finite amount of time for the MSA to "settle"
between steps. It is possible, and even likely, that the operator
can sweep too fast. To verify if the data (and trace) is
accurate, you can change the sweep action from "L-R" to
"Alternate". If the trace is unchanged while sweeping in both
directions, you can be somewhat confident that the data is
accurate. The slower the sweep, the more accurate the data.
The MSA, and any spectrum analyzer that uses a "digital sweep", is
prone to miss, or "skip" signals. This is because the step frequency can be greater than the bandwidth
of the Final Resolution Filter. The step frequency is controlled by the
values of "Span" and "Steps/Sweep". The resulting step frequency
is displayed on the right side of the Graph Window, in the set-up
parameters text. If the potential for skipping signals exists, a
notice will be displayed in the "Message" box.
"Hor. Div." drop-down box. (Horizontal
Divisions) This selects
the number of vertical reference grid lines along the horizontal
axis. Default is "10". "Sweep" options.
The following check boxes determine the sweep
preferences.
* "Linear".
This is
the default and normal sweep. All steps are equally spaced in frequency.
* "Log".
This
performs a logrithmic sweep. If checked, the "Start" and "Stop"
boxes
become active. Valid inputs for the "Start" and "Stop" box inputs
are frequencies greater than 0
(MHz). Negative frequencies and very narrow spans will not be
allowed.
* "L-R". This performs sweeping
from Left to Right, low frequency to higher frequency.
* "R-L". This performs sweeping
from Right to Left, high frequency to lower frequency.
* "Alternate". This performs
sweeping from Left to Right, then Right to Left.
"Frequency Band" drop-down box. This
determines the Band of Operation for the MSA. Default is 1G, the
original 0
to 1000 Mhz Band. 2G is 1000 MHz to 2000 MHz. 3G is 2000
MHz to
3000 MHz. When the 2G Band is selected, MSA path cable
interconnections will usually be re-configured. The Control Board will
transmit control signals to optional RF switches. "OK" button.
Clicking will close the window and cause the program to use any changes
made within the window. Some
changes made in the Sweep Parameters Window will allow the operator
only the option of "Restart". Clicking the upper right "X" box does the
same as "OK". "Cancel" button. Clicking
will close the window and any changes made within the window will be
disregarded by the program.
"Sig Gen Freq". This box is not shown for the
Basic MSA.
This is relevant for only Build Levels 2 or 3 (MSA/TG or VNA), and only when in Spectrum
Analyzer Mode. This controls the CW Signal
Generator Frequency that is available at the Tracking Generator output
connector.
The change will take effect when the "Restart"
is
clicked. Note: The Signal Generator capability
of the
MSA/TG or VNA cannot be disabled (turned off). There will always be a
signal exiting the Tracking Generator
port. The signal output is mainly the fundamental
frequency that is placed in the box. However, there
will be
other product frequencies and harmonics generated within the
MSA/TG. Sometimes
this can affect normal MSA operation. When in the Spectrum
Analyzer Mode, it is advisable to "park" the Signal Generator to a
frequency that will not affect spectrum analyzer operations. I
suggest "parking" the Signal Generator to a frequency above the
selected sweep of the Spectrum Analyzer. It is possible to
attribute strange spurious signals to the Signal Generator. If
so, move
the frequency of the Sig Gen and see if the spurious signals move or
disappear.
Sweep
Parameters Window for Spectrum Analyzer with Tracking Generator Mode "Tracking Generator". This
controls the action of the tracking generator.
This is relevant for Build Levels 2 or 3 (MSA/TG or VNA), and only when in Spectrum
Analyzer with Tracking Generator Mode. It is not shown for Build
Level 1, the Basic MSA.
The changes will take effect when the "Restart"
is
clicked. "Normal" button. Indicates the Tracking Generator output
is the same frequency as what the MSA is commanded and tuned to,
plus a value of frequency offset entered in the "Offset"
box.
When
the Normal Button is clicked, the label changes to "Reverse", and the Tracking Generator will
"reverse track" the
MSA commanded input frequency.
The Axis Windows
The Left or Right vertical Axis
Scales will display the reference values of a
measurment. The references can be changed by
the controls in their Axis Windows.
While Halted,
position the mouse
cursor over any value displayed next to the Magnitude Scale, and double
left click. The "Axis Y2" Window
will open. During the Spectrum Analyzer Mode it contains the
buttons and boxes used to control the
parameters of the magnitude trace. The Left Scale is active in
other Modes and has similar controls. "Trace Color" box. Click within the box to
open a Color Window. You may choose a variety of colors for the
trace. "Trace Width" pull-down box. You may
select 3 different trace widths. The numbers correspond to the
number of pixels used to create the trace. The default value "1"
is the best performer, and 2 or 3 are more suitable for histograms or
for print-outs.
"Trace Style" pull-down box. This box has up to 5
selections
for how the trace is displayed: * "Off"
The trace will not be displayed the Graph Window. However, the
data will be collected and the Marker Table will update. * "Norm
Erase" The data point is
connected to the previous data point by a line. Each trace will remain on the graph until the
next sweep, where it will be erased and re-written at each step.
This is the
most common display for spectrum analyzers. I should caution that
connecting data points with a line will give the visual impression that
the data is valid between data points. This is not the case for
the MSA or any digital analyzer using a "stepped" response. * "Norm
Stick" Same as
Norm Erase, except the traces will not be erased. They will remain during
subsequent sweeps. This is useful when looking at accumulated
data.
* "Histo
Erase" The data point is represented by a
Histogram. This is a
vertical line from the base of the graph to the magnitude level of the
signal. Each histogram will remain on the graph until the next
sweep, where it will be erased and re-written with new data. This is not used, nor
displayed in the SNA or VNA Modes.
* "Histo
Stick" Same as Histo Erase, except the
histograms will not be erased. They will remain during
subsequent sweeps. This is useful for
accumulated peak readings. This is not used, nor
displayed in the SNA or VNA Modes.
"Number of Divisions" pull-down
box.
You may select the number of horizontal graph reference lines, from 4
to 12. Default is "10" and is the most common. "Graph Data"
pull-down box. This will define the Scale and Trace,
depending on the MSA Function. For example: the Spectrum Analyzer
mode has three measurement options:
* "Magnitude (dBm)
* "Magnitude (Watts)
* "Magnitude (Volts) "Top
Ref"
box. and
"Bot
Ref"
box. Numbers entered into
these boxes will assign the Reference values for
the vertical scale on the Graph.
"Auto Scale"
check box. A check will allow the program to
create a scale that is appropriate for the level that is
measured. Apply a check mark here when changing an option in the
"Graph Data" pull-down box. This will assure a trace on the
graph. Uncheck this when manually entering values into the "Top
Ref" or "Bot Ref" box. "OK" button. Clicking
will close the window and cause the program to use any changes made
within the window. "Cancel" button. Clicking
will close the window and any changes made within the window will be
disregarded by the program.
Menu Items
during Spectrum Analyzer Mode
The Menu Items allow the user to
access the functions and modes of the MSA. The Menu Items depend
on the construction level of the MSA and the present Mode of
operation. The following are common to all Modes and Functions of
the MSA. I expect
Menu Items to be added and expanded
with future versions of software.
[File] (common to all Modes) [Save Image]
This will save the
contents of the graph window as a bitmap file. You will be given an
opportunity to name the file. The bitmap will contain the graph window
contents exactly as shown on screen. Be sure the window is fully
visible before you select
this menu item. The file is created by Liberty Basic, and some graphics
programs may not recognize its format. Save
Prefs and Load Prefs. Each
MSA session
opens and loads the configuration settings that are saved in a file
called "Prefs.txt". This file resides in the folder, "MSA_Prefs", which is a sub-folder of
"MSA_Info". The initial MSA session uses
default values that are determined to be the most efficient for testing
and running of a new MSA in the Spectrum Analyzer Mode. [Save Prefs] This will save the current
session's configuration settings into a text file. Sweep data
and operating calibration data is not saved. You can name it
anything but retain the ".txt" extension. I would suggest that
you retain the file,
"Prefs.txt", and name any new file, "Prefs1.txt" or "Prefs2.txt",
etc. Future sessions of MSA will always open using the file
named, "Prefs.txt". Once you have determined
how you want your MSA to open, you can replace the
existing "Prefs.txt" by over-writing it. A newly created preference file MUST be saved in the "MSA_Prefs"
Folder. I suggest you store only Preference files (configurations) in
this folder. You can save and store as many as you want. [Load Prefs] You
can load any ".txt"
file that is in the folder, "MSA_Prefs". This will
re-configure the present MSA session into the configuration that is
stored in that file. [Load Data] [Save Data] This will save the "Sweep Data",
which is the data collected during the most recent sweep of the MSA. [Load Front End] [Save Debug Info] This is
a
special feature for trouble shooting a faulty MSA. There is much
more work to be done in the area but it is designed to be used by me or
another MSA user to help a builder with problems. Basically,
the builder would configure his MSA into a problem condition. He
can
then click "Save Debug File". A folder
named "xxDebug" will be created and installed into the "MSA_Software"
folder. He can then send this Debug folder to me or
another user/helper. We can convert the files to allow our MSA to
run, using the same data taken by the builder. This is not fully
active yet. I will
update
this paragraph when it is. [Load Debug Info] This
will configure the helper's MSA to the configuration of the builder's
MSA. Again, much more to be written on this.
[Edit]
(common to all Modes) [Copy Image]
This
will copy the contents of the graph window to the clipboard, so you can
paste it into another application. The clipboard will contain the graph
window contents exactly as shown on screen (except the cursor will not
be captured), so be sure the window is fully visible before you select
this menu item.
[Setup]
(common to all Modes) [Hardware Config
Manager] This will open the "Configuration
Manager" window. This window will allow the
operator to modify any MSA default
value. A complete description for this window is in the page, Initial Set-Up and Calibration for the MSA. [Initial Cal Manager] This will open the "Calibration File
Manager" window for the user to calibrate the MSA or change values in the
calibration tables. A complete description for
this window is in the page, Initial
Set-Up and Calibration for the MSA. [Special Tests] This will open the "Special Tests"
window.
From there, other Functions and Special Tests can be performed. I will
describe the use of these items in the sections that use this
window. [PDM Calibration]This will open the "PDM Calibration
Manager" window. However, it should only be used during VNA Mode. [Primary Axis] This will open a "Primary Axis"
window and allow the user to change the primary axis to either Left
Axis (Y1), the left side, or Right Axis (Y2), the right side. This is a
preference to the user. It should be noted that several of the MSA
functions are specifically designed to operate only on the Primary Axis.
Markers: P+ and P- automatically attach themselves to the trace
governed by the Primary Axis.
Both the Filter Analysis Function and the Crystal Analysis Function are associated with only
the Primary Axis. Therefore, Magnitude measurement must be on the
Primary Axis for these Functions to work.
[Options]
(common to all Modes) [Appearances]
This will open a "Graph
Appearance" Window and allow the user to select preferences for the
Graph colors. See, Changing
the Graph Appearance in the MSA
by
Sam Wetterlin. [Markers]
This will open a "Marker Options"
window. More will be written on this window at a later time. [Sweep] This will open the "Sweep Parameters"
window. Same as double left clicking below the graph to open the
window. [Show Variables] This will open a "Variables
Window" on the right
side of the Graph Window. It will contain many of the variables,
and
their values, that are used in the program. All data is relevant
for the step at which the sweep was Halted or for the step at which the
Left Mouse button is double clicked. The sweep can be resumed
with the Variables Window open and the data will update
with each step. However, the Variables Window may become hidden
behind the Graph Window. To view, go to the Windoze bottom tray
and click the Variables Window Tab.
These are the variables displayed in the Variables
Window, but the Function of the MSA will
determine if the values are valid: this
step = step number
of the sweep dds1output = output frequency
of DDS 1 LO1 = output frequency of LO 1
or VCO 1 pdf1 = phase detector frequency
of PLL 1 ncounter1 = RF
divide ratio of PLL 1 (pdf1 = LO1/ncounter1) Bcounter1
= divide
ratio of B counter inside
PLL 1
Acounter1 = divide ratio of A counter inside
PLL 1 fcounter1
= fractional divider of
PLL 1, but only if it is a Fractional N PLL, otherwise it is 0 rcounter1 = Reference clock
divide ratio of PLL 1 (pdf1 = dds1output/rcounter1)
LO2 = output frequency of LO 2 or VCO
2
pdf2 = phase detector frequency of PLL
2 ncounter2
= RF divide ratio of PLL
2 (pdf2 = LO2/ncounter2) Bcounter2 = divide ratio of B counter inside
PLL 2
Acounter2 = divide ratio of A counter inside
PLL 2
rcounter2=
Reference clock divide ratio of
PLL 2 (pdf2 = masterclock/rcounter1)
LO3=
output frequency of LO 3 or VCO
3
pdf3=
phase detector frequency of PLL
3 ncounter3 =
RF divide ratio of PLL 3 (pdf3
= LO3/ncounter3)
Bcounter3=
divide
ratio of B counter inside
PLL 3
Acounter3=
divide
ratio of A counter inside
PLL 3
fcounter3=
fractional divider of PLL 3,
but only if it is a Fractional N PLL, otherwise it is 0
rcounter3=
Reference clock divide ratio of
PLL 3 (pdf3 = dds3output/rcounter3)
dds3output=
output frequency of DDS 3 Magdata
= the actual bit count of
the Magnitude Analog to Digital Converter power = the MSA input
power level, processed as Magnitude, in dBm Phadata=
the
actual bit count of the Phase Analog to Digital Converter PDM
= the state of the Phase
Detector Module, Normal is 0, Inverted is 1. The value displayed on the
far right is the raw phase of the PDM, in degrees. Real Final I.F. = actual
frequency of the I.F., entering the Log
Detector glitchtime = During
the first initial sweep after starting the program, the variable
"glitchtime" is given a value representing a relative
speed of the computer. A "glitchtime = 67.5675676"
means it will complete about 68 computer operations in one
millisecond.
Higher values will occur with faster computers. This value is
used in the software to make everyone's MSA somewhat uniform in speed. SG/TG Out = the actual frequency of the signal
exiting the TG port.
[Data]
Items under the [Data] menu depend on the MSA Build
Level and the Mode of operation. Sub-menu items can be
selected to display data that
was collected during the previous full sweep, even if it was Halted before
completion. Data can
be
copied and pasted into an external program for post processing and
evaluation. Many spreadsheet programs, such as Excel, can perform
some amazing signal evaluations. This is a very convenient method
for exporting data into those spreadsheets. The data are
displayed in a text format, within a Data Window. Each Data
Window has options for
Selecting and Copying. I expect items to change or expand in
future revisions.
[Data] (during Spectrum Analyzer Mode) [Graph Data] - This will open
a Data Window and display 2
columns of values, with a row of values for each frequency step in one full sweep. The data columns are: Freq(MHz)-
The frequency at
each step
Processed Data that is
referenced on the Right Axis (Magnitude) [Input Data] - This will open
a Data Window and display 5
columns of values, with a row of values for each frequency step in one full sweep. The data columns are:
Step
Number- from 0 to value of
"Steps/Sweep"
Freq(MHz)- The frequency at
each step Calc
Magnitude Input- Calculated Magnitude Input to MSA (in
dBm),
a process using Factors from the Path and Frequency Calibration Tables
Mag
AtoD Bit Val- The "raw" bit
value of
Mag AtoD Converter, no processing done
Freq Cal Factor- Frequency
Calibration Factor, interpolated from the
Mag vs. Frequency Table. The table was derived during the Initial
MSA
Calibration.
[Functions]
(during Spectrum Analyzer Mode)
Items under the [Functions] menu
depend on the MSA Build Level and the Mode of operation. [Filter Analysis]
This will open a "Filter Analysis" window for placing markers at
various points on the trace. The maximum response on the Graph
is assumed to be a filter response. The 3 dB points are
calculated and used to create analysis information, next to the Marker
Information. This Function
has its own dedicated Web Page. See: The
MSA as a Filter Analyzer.
[Operating
Cal] This menu item is not shown in the
Spectrum Analyzer Mode. [Perform Cal]
- This will open the window,
"Perform Calibrations". This will allow the operator to perform a
Reference Line Calibration, which preceeds a standard SNA or VNA
measurement. This calibration will "normalize" the sweep to 0 dB
for Magnitude and 0 degrees for Phase for the VNA. After this
calibration,
all sweeps will be Referenced to this "normalized" calibration.
When either of the following calibrations are performed, insure that
the Plane Extension is "0", found in the "Sweep Parameters"
window. The Band Sweep
Calibration will calibrate the SNA or VNA
for a specific frequency range. The calibration values are stored
in local memory and will be deleted when the MSA session is
closed. The accuracy is valid only when the subsequent
sweeps are identical to the sweep frequency that is calibrated. The Baseline
Calibration is normally the sweep
frequency range of the MSA/VNA, which is .1 MHz to 1000 MHz. (greater than 0 Hz). This calibration is
stored in a file, and is
placed into the same folder as the MSA software. It is not
deleted at the end of the MSA session. It will be accessable for
all
future sessions. Although this calibration is quite accurate at
the time it is taken, it may not be accurate at a later time, due to
temperature differences. But, it is a valuable
for "ballpark" measurements. The
Verification VNA showed that, after one month, the Baseline Cal had
shifted less than 4
degrees and had a ripple of less than 0.5 degrees. [Reference To]
- This will open a window to select the SNA or VNA to reference its
measurements to the appropriate calibration table. On initial
running, the Cal tables are filled with zeros. It is
the same thing as selecting "No Reference". If a Baseline
Calibration has been performed, the file will be accessed and the
calibration will be valid. "No Reference" is the default.
[Mode] Not shown for the MSA Build
Level 1 (Basic MSA). [Spectrum Analyzer] with Signal
Generator. The TG outport will be a fixed frequency as selected in the
Sweep Parameters Window (Sig Gen Freq) [Spectrum Analyzer with Tracking
Generator]. The TG outport will be the same
frequency as the Step Frequency during Sweep. [SNA Transmission] Scalar
Network
Analyzer, Transmission Mode. This mode is used for
measuring the
S21or S12 Parameters of a
Device, Magnitude only. Sometimes used in conjunction with a test
fixture
containing the Device. Shown for MSA Build Level 2 (MSA/TG) only. [VNA Transmission] Vector Network
Analyzer, Transmission Mode. This mode is used for
measuring the
S21or S12 Parameters of a
Device. Sometimes used in conjunction with a test fixture
containing the Device. Shown for MSA Build Level 3 (VNA) only. [VNA Reflection] Vector Network
Analyzer, Reflection Mode. This mode is used for
measuring the S11 or S22 Parameters of a Device using some form of
Reflection Bridge. Shown for MSA Build Level 3 (VNA) only.
Control during Scalar
Network Analyzer-Transmission Mode Menu Items during SNA-Transmission Mode [File] same as Spectrum Analyzer Mode [Edit] same as Spectrum Analyzer Mode [Setup] same as Spectrum Analyzer Mode [Options] same as Spectrum Analyzer Mode
[Data]
(during SNA-Transmission Mode)
[S21 Parameters] - Final S21 Data, in Touchstone
format. The S21 Angle is meaningless. [Input Data] - This will open
a Data Window and display 5
columns of values, with a row of values for each frequency step in one full sweep. The data columns are:
Step
Number- from 0 to value of
"Steps/Sweep" Freq(MHz)- The frequency at
each step Calc
Magnitude Input- Calculated Magnitude Input to MSA (in
dBm),
a process using Factors from the Path and Frequency Calibration Tables Mag
AtoD Bit Val- The "raw" bit
value of
Mag AtoD Converter, no processing done Freq Cal Factor- Frequency
Calibration Factor, interpolated from the
Mag vs. Frequency Table. The table was derived during the Initial
MSA
Calibration. [Installed Line Cal] - This
will open
a Data Window and display 3
columns of values: Freq(MHz)- The frequency at
each step Cal_Mag- The Magnitude
Calibration Factor from the Line Calibration in use during the sweep Cal_Ang- This is not used. The
data will always be 0.00
[Functions]
(during SNA-Transmission Mode) [Filter Analysis]
This will open a "Filter Analysis" window for placing markers at
various points on the trace. The maximum response on the Graph
is assumed to be a filter response. The 3 dB points are
calculated and used to create analysis information, next to the Marker
Information. This Function
has its own dedicated Web Page. See: The
MSA as a Filter Analyzer.
[Crystal Analysis] The response on the Graph
is assumed to be a series crystal response. This will open a
"Crystal Analysis" window for the determination of crystal
parameters. This Function
has its own dedicated Web Page. See The
MSA as a Crystal Tester.
[RLC Analysis]Provides a simple way to
analyze a complex circuit by transforming to an equivalent Resistor,
Inductor, Capacitor circuit. However, since phase is not
measured, measurement is somewhat limited. This Function
has its own dedicated Web Page. See The
MSA for RLC Analysis.
[Component Meter]Provides a simple way to
measure resitors, capacitors and
inductors, much like
an RCL meter. However, since phase is not
measured, measurement is somewhat limited. This Function
has its own dedicated Web Page. See The
MSA for Component Measurement.
[Operating
Cal] during SNA-Transmission Mode [Perform Cal]
- This will open the window,
"Perform Calibrations". This will allow the operator to perform a
Reference Line Calibration, which preceeds a standard SNA
measurement. This calibration will "normalize" the sweep to 0 dB
for Magnitude. After this calibration,
all sweeps will be Referenced to this "normalized" calibration.
When either of the following calibrations are performed, insure that
the Plane Extension is "0", found in the "Sweep Parameters"
window. The Band Sweep
Calibration will calibrate the SNA
for a specific frequency range. The calibration values are stored
in local memory and will be deleted when the MSA session is
closed. The accuracy of the SNA is valid only when the subsequent
sweeps are identical to the sweep frequency that is calibrated. The Baseline
Calibration is normally the sweep
frequency range of the MSA/TG, which is .1 MHz to 1000 MHz. (greater than 0 Hz). This calibration is
stored in a file, and is
placed into the same folder as the MSA software. It is not
deleted at the end of the MSA session. It will be accessable for
all
future sessions. Although this calibration is quite accurate at
the time it is taken, it may not be accurate at a later time, due to
temperature differences. But, it is a valuable
for "ballpark" measurements. The
Verification MSA showed that, after one month, the Baseline Cal had
shifted less than .1 dB.
[Reference To]
- This will open a window to select the
SNA to reference its
measurements to the appropriate calibration table. On initial
running of the SNA, the Cal tables are filled with zeros. It is
the same thing as selecting "No Reference". If a Baseline
Calibration has been performed, the file will be accessed and the
calibration will be valid. "No Reference" is the default.
[Mode]
for MSA/TG
Click
to enter any mode of operation. [Spectrum Analyzer]
Spectrum Analyzer Mode, with Signal Generator [Spectrum Analyzer with TG]
Spectrum Analyzer Mode, with Tracking Generator [SNA Transmission] Scalar
Network
Analyzer, Transmission Mode. This mode is used for
measuring the
S21or S12 Parameters of a
Device, Magnitude only. Sometimes used with a test
fixture
containing the Device.
Control during VNA
Transmission Mode
When the MSA
Program "spectrumanalyzer" is run, the MSA will
automatically begin sweeping in the Spectrum Analyzer Mode, by default. The VNA-Transmission Mode is
entered from the Menu / Mode. The following is a screen print of
the Graph Window and Graph Display while sweeping in the VNA-Transmission Mode. A Crystal Filter is the
DUT (Device Under Test), with a 10 dB attenuator on each end. Graph Display, VNA-Transmission Mode:
Controls within the Graph Window
are no different than those described when in the Spectrum Analyzer
Mode.
Sweep
Parameters Window,
VNA-Transmission Mode:
Controls within the Sweep
Parameters Window are no different than those described when in the
Spectrum Analyzer Mode, with these exceptions:
Neither the Signal Generator nor the Tracking
Generator is accessable. The Tracking Generator is automatically
commanded for Normal Tracking and no Offset.
Note: The
"Select
Final Filter Path:" drop-down box
must have the correct Path selected for VNA operation. All VNA
calibrations are performed in a single Path. Usually, this is
Path 1. "PDM Inversion
(deg) box. This box displays the current calibration for
the PDM. It can be changed in this box for special testing. "Plane Extension"
box. This adds or subtracts (-) time into the
calculations. Also referred to as "Reference Plane
Extension". It is the same as physically adding cable length
within the Reference Source circuit. This is a very good way to
factor out time delay effects of transitional components surrounding
the DUT, such as barrel connectors, test jig, etc. Just for
reference, the Verification unit requires a plane extension of "3.2" ns
to factor out its internal delays. A new value (in nanoseconds)
may be entered and the "Recalc" button clicked. The Graph will
immediately retrace with the extension value. "Video
Filter BW" and "Wait (ms)" boxes. As with
Spectrum Analyzer
mode, we can set the video filter to wide, middle or narrow. The
narrower the
setting, the longer the settling time required when stepping from point
to
point, and
the more Wait time we need to specify. When phase is involved, precise
measurements are likely to require extra wait time, and settings of
15-50 ms
are typical. 100-150 ms of Wait time may be required for the most
precise
measurements. When the PDM measures raw phase within a certain
“inaccurate
zone”, the MSA inverts its phase reference, remeasures,
and adjusts for the phase shift caused by the inversion. This inversion
causes
a large, abrupt shift in the raw phase measurement, which requires an
extra-long settling time. The stronger the video filter (larger
capacitor), the
more Wait time is required. The MSA automatically imposes the extra
delay, but
it is important that you set the Video Filter in the sweep parameters
window to
match the actual hardware setting, so the software knows the state of
the video
filter. (The software setting does not actually set the video filter at
the
present time; it just informs the software of the setting.)
The Y Axis Windows, Axis Y1 (left) and Axis
Y2 (right) The
data to be
graphed on each axis can be selected from the Y-axis parameters dialog,
which
opens when the users double-clicks in the area of the corresponding
axis
grid-line labels. This dialog is in the same format as for Spectrum
Analyzer
mode, but contains a different selection of graphs, as shown in the
following:
--S21 Magnitude (db).
These is conventional, processed Magnitude using a
reference calibration. --S21 Phase Angle.
These is conventional, processed Phase using a
reference calibration. --Raw
Power (dBm) and
--Raw Phase Angle.
These are the "absolute" measurements without adjustment for a
reference calibration.
It may
be desired to display these in unusual situations. --Insertion
Loss. This is
simply the negative of the S21 dB value.
For a bandpass filter, instead of graphing
a “hill”,
this will graph a “valley” with maximum transmission
(lowest loss) at
the
bottom. --S21
Group Delay. This is
the negative of the change in phase
over the change in frequency. It is sometimes a useful value. Due to
being
calculated from rates of change, it is very susceptible to noise, which
causes
the graph to be very erratic. This graph will ultimately be replaced by
an item
under the Analysis menu which will produce a smoother graph. --None.
This causes nothing
to be graphed on that axis, the axis
to be blank, and no value for that axis to be displayed in the Marker
area. (As
opposed to using Trace Style to turn the trace off, which
leaves the axis labels in place and allows the axis values to be
displayed in
the Marker area.) The
“Histogram”
option for Trace Style is not available for either axis in Transmission
mode.
Menu Items during VNA-Transmission
Mode [File] same as Spectrum Analyzer Mode [Edit] same as Spectrum Analyzer Mode [Options] same as Spectrum Analyzer Mode [Setup] same as Spectrum Analyzer Mode,
except: [PDM Calibration]This will open the "PDM Calibration
Manager" window. This window will allow the
operator to calibrate the Phase Detector Module. It is
referred to during the Calibration Procedure for the MSA.
[Data]
(during VNA-Transmission Mode) [S21 Parameters] - Final S21 Data, in Touchstone
format [Graph Data] - This will open
a Data Window and display 3
columns of values, with a row of values for each frequency step in one full sweep. The data columns are: Freq(MHz)- The frequency at
each step Processed Data that is referenced on
the Left Axis Processed
Data that is referenced on the Right Axis [Input Data] - This will open
a Data Window and display 7
columns of values: Step
Number- from 0 to value of
"Steps/Sweep" Freq(MHz)-
The frequency at
each step Calc
Magnitude Input- Calculated Magnitude Input to MSA (in
dBm),
a process using Factors from the Path and Frequency Calibration Tables Mag
AtoD Bit Val- The "raw" bit
value of
Mag AtoD Converter, no processing done Freq
Cal Factor- Frequency
Calibration Factor, interpolated from the
Mag vs. Frequency Table. The table was derived during the Initial
MSA
Calibration. Pha
AtoD Bit Val- The "raw" bit
value of Phase AtoD Converter, no processing done Processed
Phase- The processed value
of Phase (in degrees) as plotted on the graph
[Installed Line Cal] - This
will open
a Data Window and display 3
columns of values: Freq(MHz)- The frequency at
each step Cal_Mag- The Magnitude
Calibration Factor from the Line Calibration in use during the sweep Cal_Ang- The Phase Calibration
Factor from the Line Calibration in use during the sweep
[Functions]
(during VNA-Transmission Mode) [Filter Analysis]
This will open a "Filter Analysis" window for placing markers at
various points on the trace. The maximum response on the Graph
is assumed to be a filter response. The 3 dB points are
calculated and used to create analysis information, next to the Marker
Information. This Function
has its own dedicated Web Page. See: The
MSA as a Filter Analyzer.
[Crystal Analysis] The response on the Graph
is assumed to be a series crystal response. This will open a
"Crystal Analysis" window for the determination of crystal
parameters. This Function
has its own dedicated Web Page. See The
MSA as a Crystal Tester.
[RLC Analysis]Provides a simple way to
analyze a complex circuit by transforming to an equivalent Resistor,
Inductor, Capacitor circuit. This Function
has its own dedicated Web Page. See The
MSA for RLC Analysis.
[Component Meter]Provides a simple way to
measure resitors, capacitors and
inductors, much like
an RCL meter. This Function
has its own dedicated Web Page. See The
MSA for Component Measurement.
[Operating
Cal]
for VNA-Transmission Mode [Perform Cal]
- This will open the window,
"Perform Calibration". This will allow the operator to perform a
Reference Line Calibration, which preceeds a standard VNA
measurement. This calibration will "normalize" the sweep to 0 dB
for Magnitude and 0 degrees for Phase. After this calibration,
all sweeps will be Referenced to this "normalized" calibration.
When either of the following calibrations are performed, insure that
the Plane Extension is "0", found in the "Sweep Parameters"
window. The Band Sweep
Calibration will calibrate the VNA
for a specific frequency range. The calibration values are stored
in local memory and will be deleted when the MSA session is
closed. The accuracy of the VNA is valid only when the subsequent
sweeps are identical to the sweep frequency that is calibrated.
The Baseline
Calibration is normally the sweep
frequency range of the VNA, which is .1 MHz to 1000 MHz. (greater than 0 Hz). This calibration is
stored in a file, and is
placed into the same folder as the MSA software. It is not
deleted at the end of the MSA session. It will be accessable for
all
future sessions. Although this calibration is quite accurate at
the time it is taken, it may not be accurate at a later time, due to
temperature differences. But, it is a valuable
for "ballpark" measurements. The
Verification MSA showed that, after one month, the Baseline Cal had
shifted less than .1 dB and less than 4
degrees with ripple of less than 0.5 degrees.
[Reference To]
- This will open a window to select the
VNA to reference its
measurements to the appropriate calibration table. On initial
running of the VNA, the Cal tables are filled with zeros. It is
the same thing as selecting "No Reference". If a Baseline
Calibration has been performed, the file will be accessed and the
calibration will be valid. "No Reference" is the default.
[Mode]
Click
to enter any mode of operation. [Spectrum Analyzer]
Spectrum Analyzer Mode, with Signal Generator [Spectrum Analyzer with TG]
Spectrum Analyzer Mode, with Tracking Generator [VNA Transmission] Vector Network
Analyzer, Transmission Mode. This mode is used for
measuring the
S21or S12 Parameters of a
Device. Sometimes used with a test fixture
containing the Device. [VNA Reflection] Vector Network
Analyzer, Reflection Mode. This mode is used for
measuring the S11 or S22 Parameters of a Device using some form of
Reflection Bridge.
Control during
VNA-Reflection Mode
When the MSA
Program "spectrumanalyzer" is run, the MSA will
automatically begin sweeping in the Spectrum Analyzer Mode, by default. The VNA-Reflection Mode is
entered from the Menu / Mode. The following is a screen print of
the Graph Window and Graph Display while sweeping in the VNA-Reflection Mode. A Crystal Filter is the
DUT (Device Under Test), with a 10 dB attenuator on each end. Graph Display, VNA-Reflection Mode: Smith
Chart, VNA-Reflection Mode:
Menu
Items during VNA-Reflection Mode
[File] same as Spectrum Analyzer Mode [Edit] same as Spectrum Analyzer Mode [Options] same as Spectrum Analyzer Mode [Setup] same as Spectrum Analyzer Mode,
except: [PDM Calibration]This will open the "PDM Calibration
Manager" window. This window will allow the
operator to calibrate the Phase Detector Module. It is
referred to during the Calibration Procedure for the MSA.
[Data]
(during VNA-Reflection Mode)
[S11 Parameters] - Final S11 Data, in Touchstone
format
[S11 Derived Data] - 18 Columns of Data collected.
More to be written here. [Graph Data] - This will open
a Data Window and display 3
columns of values, with a row of values for each frequency step in one full sweep. The data columns are: Freq(MHz)-
The frequency at
each step Processed
Data that is referenced on
the Left Axis Processed Data that is
referenced on the Right Axis [Input Data] - This will open
a Data Window and display 7
columns of values: Step
Number- from 0 to value of
"Steps/Sweep" Freq(MHz)-
The frequency at
each step Calc
Magnitude Input- Calculated Magnitude Input to MSA (in
dBm),
a process using Factors from the Path and Frequency Calibration Tables Mag
AtoD Bit Val- The "raw" bit
value of
Mag AtoD Converter, no processing done Freq
Cal Factor- Frequency
Calibration Factor, interpolated from the
Mag vs. Frequency Table. The table was derived during the Initial
MSA
Calibration. Pha
AtoD Bit Val- The "raw" bit
value of Phase AtoD Converter, no processing done Processed
Phase- The processed value
of Phase (in degrees) as plotted on the graph
[Cal Reference] - The installed line cal, which
in reflection mode is the data from the Open scan, but with the
Series fixture it is the data from the Short scan.
[OSL Info] - S11 of the cal
standards, and the A, B, C OSL coefficients
[Functions]
(during VNA-Reflection Mode)
[RLC Analysis]Provides a simple way to
analyze a complex circuit by transforming to an equivalent Resistor,
Inductor, Capacitor circuit. This Function
has its own dedicated Web Page. See The
MSA for RLC Analysis.
[Coax Parameters]Transmission Line Analysis. This Function
has its own dedicated Web Page. See The
MSA as a Transmission Line Analyzer.
[Operating
Cal]
for VNA-Reflection Mode [Perform Cal]
- This will open the window,
"Perform Calibrations". This will allow the operator to perform a
Reference Line Calibration, which preceeds a standard VNA
measurement. This calibration will "normalize" the sweep to 0 dB
for Magnitude and 0 degrees for Phase. After this calibration,
all sweeps will be Referenced to this "normalized" calibration.
When either of the following calibrations are performed, insure that
the Plane Extension is "0", found in the "Sweep Parameters"
window. The Band Sweep
Calibration will calibrate the VNA
for a specific frequency range. The calibration values are stored
in local memory and will be deleted when the MSA session is
closed. The accuracy of the VNA is valid only when the subsequent
sweeps are identical to the sweep frequency that is calibrated. The Baseline
Calibration is normally the sweep
frequency range of the VNA, which is .1 MHz to 1000 MHz. (greater than 0 Hz). This calibration is
stored in a file, and is
placed into the same folder as the MSA software. It is not
deleted at the end of the MSA session. It will be accessable for
all
future sessions. Although this calibration is quite accurate at
the time it is taken, it may not be accurate at a later time, due to
temperature differences. But, it is a valuable
for "ballpark" measurements. The
Verification MSA showed that, after one month, the Baseline Cal had
shifted less than .1 dB and less than 4
degrees with ripple of less than 0.5 degrees. [Reference To]
- This will open a window to select the
VNA to reference its
measurements to the appropriate calibration table. On initial
running of the VNA, the Cal tables are filled with zeros. It is
the same thing as selecting "No Reference". If a Baseline
Calibration has been performed, the file will be accessed and the
calibration will be valid. "No Reference" is the default.
[Mode]
Click
to enter any mode of operation. [Spectrum Analyzer]
Spectrum Analyzer Mode, with Signal Generator [Spectrum Analyzer with TG]
Spectrum Analyzer Mode, with Tracking Generator [VNA Transmission] Vector Network
Analyzer, Transmission Mode. This mode is used for
measuring the
S21or S12 Parameters of a
Device. Sometimes used with a test fixture
containing the Device. [VNA Reflection] Vector Network
Analyzer, Reflection Mode. This mode is used for
measuring the S11 or S22 Parameters of a Device using some form of
Reflection Bridge.
