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This page explains all of the detailed settings for the DrzTrack program. Here are links to the various topics

Configuration|  Switches and Led  |  Tracking With Other Programs  |  Program Setup  |  Polarization Control | Positional Offsets  |  Absolute Encoder Programming

 

Detailed Configuration Settings
When first getting started, all that is required is to select the correct encoder type for Azimuth and for Elevation, and set the appropriate ranges, but once you have the initial setup and testing done you may need to fine tune the controller to your requirements. The configuration window and explanation for each item follow. Since the settings for azimuth and elevation are the same, I will only explain for azimuth. Note that hovering the mouse pointer over any of the fields will cause a 'tool tip' to pop up, giving more explanation about what that field is for.

Note that this screen is separated into upper and lower sections.  The upper section could be called the mount section.  It is where you select the encoder types and calibration and tracking ranges and other settings that are specific to the mount.

The lower section is for the motion controls.  These values specify various timing and speed control settings that can be tailored to your particular needs.  In the simplest case the motion controls will be the same for all bands that you may be using this mount for.  But if you have more than one band on your mount then it may be that movement settings would need to be different for some bands.

If that is the case then uncheck the box labeled "Use same Controls for all Bands".  Then a drop down box will appear, showing the current band that you have selected in the main dialog.  You can set all the values for that band and then set a new band in the drop box and specify the settings for that band, etc.  Note that when you switch to a band that does not yet have any values set up, the values of the band you were on remain in the fields.  In that way you are able to copy settings from one band to another and then modify as desired.

Starting with DrzTrack Version 5.21, a fourth encoder type has been added.  This is the Slew Drive.  Now the encoder selections are drop down boxes instead of the radio buttons shown here for version 5.20.

 
Encoder settings for the Mount
 

Disable Azimuth or Elevation
For DrzTrack version 5.11 a new feature has been added here.  You can disable movement in either (or both) directions using the 'Disable' check boxes.  When  you do this, the motor for the disabled direction cannot be turned on by DrzTrack or the controller.  This is useful for situations where only one direction is able to be controlled automatically.

Calibration Min and Max
Calibration range should be set to the points that you wish to use when calibrating the controller.  This allows the controller to calculate the number of degrees for each change in position from the encoder, and set the exact current position of the antenna.

Usually it is best to use standard positions like 0-360 or 0-90*, but your situation may require you to use something else.  Note that the F1EHN and Nova programs do not handle rotation values greater than 360 degrees, so even if you can rotate your antenna in a greater range, 360 degrees is all you will be able to use with these programs.

As of version 2.11 and firmware version 2.4, setting up your azimuth system with a south stop is supported.  Check the 'South Stop' box above.  The program will ask you if you wish to use default settings.  Normally you should click 'Yes', and then modify where needed.  The default settings for south stop set the calibrate and tracking Min/Max to 180 degrees, since the south stop is at 180 degrees.

*For absolute inclinometers, and shaft encoders with 1:1 gearing, it is necessary to use a 360 degree range as the calibrate end points. See the absolute encoder paragraphs on the Control Program page.
 
Tracking Min and Max
The tracking range is used to set the limits that you wish the antenna to move to during actual tracking.  These values can be either greater or less than the calibration min and max points.  For example, you might have your elevation calibration point set at -10 degrees, but during tracking want it to stop at zero degrees.

Defaults Button
Clicking the Azimuth or Elevation defaults button at any time will load a set of default values into the screen fields of the configuration dialog. These defaults are slightly different depending upon what encoder you have selected. This provides an easy way to get a reasonable starting point for changes you may wish to make.
 
Antenna Movement Controls
 

Move Precision and Move Timeout
Move precision and Move timeout work together to set the controller's motion detector and emergency shutdown feature. In normal operation the controller receives motion commands from the controlling program. It then operates the relay to start a position motor. The antenna starts moving and the controller monitors and reports the current position back to the controlling program. When the antennas reach the desired position a stop command is sent and the controller disengages the motor relay. However if the antenna rotation mechanism is jammed, or a stop is reached, the antenna may not move when commanded. This is where the motion detector comes into play.

The Move Timeout value specifies a number of seconds, from 0 to 60, with a default value of 5 seconds. As long as the antenna is moving, the controller board checks every 5 seconds (or whatever period you have Move Timeout set for) to see if the antenna has moved during that period. It compares the position at the beginning of the period to the current position. If the values are the same, or not reasonably different, the controller goes into it's emergency shutdown procedure. It stops all motion motors and disables itself so it will not act on any further motion commands from the controlling program.

However it is not sufficient to merely check to see that the antenna has not moved at all. Even a jammed antenna may rock back and forth slightly as the motors attempt to move it. If the antenna were to hit something with a little 'give' like a tree branch, it may rock back and forth quite a bit. This would provide enough motion to 'fool' the motion detector. For this reason we have Move Precision. Move precision is a value, in tenths of a degree, of how much motion can be reasonably expected from the antenna in the period specified by Move Timeout. The default value is 10 tenths (1 degree). The minimum value is 1 tenth and the maximum value is 100 (10 degrees).

Starting with DrzTrack version 5.11 the minimum Move Precision value can be set to zero.  Then motion detection is completely disabled for that direction.  This could be necessary in some unusual circumstances, but it is also dangerous to allow antenna motors to run when the antenna is jammed somehow.  So you will get a warning when you disable motion sensing and you must confirm that is what you want to do.  Also, when motion sensing for any direction is disabled there will be a status message in the main window showing that motion sense protection is disabled.

So, with default settings, if the antenna does not move at least 1 degree every 5 seconds, the emergency shutdown will operate. Your antennas may move significantly faster or slower than this, or you may wish to check more often or more seldom than every 5 seconds. Set the values of Move Timeout and Move Precision to suit your installation.

Once the emergency shutdown has operated, the controller will accept no more commands until it has been reset. This can be done with the reset button on the DrzTrack main window, or by power cycling the controller board.

Restart Time
Most antenna rotation mechanisms cannot instantly reverse direction without the possibility of damage to the mechanism or to the antenna itself. The Restart Time setting is used to prevent whiplash. It is the time, in seconds, that the antennas must be stopped before starting motion again. The value can range from 0 to 15 seconds.
 
Slow Degrees (Speed Control)
There are several modes and methods of speed control available, depending on your setup.  There is a Slow speed method and a Jog method.  Look at the next paragraph for Jog information.  Slow speed is controlled by the variable called 'Slow Degrees'.  This has two modes depending upon your control program.

Slow speed is controlled by pins 7 and 8 of the male DB9 connector (X1).  Pin 7 will go high when the elevation should turn slowly, and pin 8 is used for azimuth.  You need to connect these pins to your own external circuitry to reduce the speed of your motors.

F1EHN:  If you are using the F1EHN Tracker, the value is not degrees, but seconds.  Setting a value other than zero activates this function.  Possible values are 0 to 255 seconds.  Each time the motor is started the slow output pin will be active (high).  After the number of seconds specified in Slow Degrees have elapsed the voltage at pin 7 or 8 will go low, indicating that you can increase motor speed.  There are no speed control outputs for stopping the motors but most systems will 'coast', making stop speed control unnecessary.

Other Programs:  For all other programs the value you put into the Slow Degrees field is the number of degrees, from 0 to 255 from either side of the target position that the slow outputs will be activated.  This works for both starting and stopping the antenna, so if you use the default value of 10 degrees, the slow outputs will be active whenever the antenna is within 10 degrees of the target.

Jog Speed Control
The second method of speed control is called jogging.  This works by starting and stopping the motors periodically when the antenna is near the target.  The 'Slow Degrees' value controls the range in which jogging is active, and the settings are the same as described above for "Other Programs".  Jogging is enabled for each motor by checking the 'Jog Control' check box.  Then you can specify the length of time that each motor will be on, and the length of time that it is off.

For firmware versions prior to 5.03, the default values are 1/2 second on, and 1 second off, but they can be set to any value from 0 to 255, in tenth seconds.  So the on and off times are between 0 and 25.5 seconds.  If you have an all electronic way to switch your motors on and off, or really good relays, you could switch the motors on and off each tenth of a second, which should result in a smooth half speed.

We have discovered that for some mounts it is necessary to be able to control the jog speed to shorter values than .1 seconds.  So, starting with firmware version 5.03, the jog time increment is now .01 seconds, allowing setting jog value (for both on and off times) between 0 and 2.55 seconds (Jog field will read 0 - 255).

Stop and Start Precision
Some programs do not monitor the position of the antenna, but rather only send the desired position to the controller. So it is up to the controller to determine when the antenna has reached the desired position, and stop motion. The Stop Precision is a measurement of how close to the specified position the antenna must be, before it is stopped. The value is in tenths of a degree and ranges from -128 to +127 (-12.8 to +12.7 degrees).  The Start Precision specifies how far beyond the current antenna position the target can move before the antenna will be started moving again.  The value is in tenths of a degree and ranges from 0 to 255 (0 to 25.5 degrees).

Note that when negative values of Stop Precision are specified, the antenna will actually move past the target before it stops.  So if the value is -20, the antenna would move two degrees past the moon before it stops.  In that case, the value of Start Precision cannot be less than 20 (+2 degrees).  The DrzTrack program will not allow you to enter values for Stop and Start precision that result in an overlap.

These setting are used for all tracking programs except for F1EHN, which handles stopping the antenna internally, sending a stop command to the controller when needed.

Send Changes to Controller Button
Once you have entered the desired values, use the Send button to save those values. They are sent to the controller board and stored in it's nonvolatile memory. The next time you enter the configuration window you will see the new values that you set.
 

Save and Restore Settings Buttons
These buttons allow you to save the current configuration, including current antenna positions and counts, to your PC, and to restore them when desired.  Click for Details.

 


Switch and LED Configuration
Clicking the Switch and LED configuration button brings up the following Dialog box.  Currently the switches are fixed function, and there are no options.  For firmware versions prior to 5.01, switch 3 has an option to be unused or to specify the resolution for the absolute encoders.  Switch 4 is unusable and must remain in the off (up) position at all times.  In the future more switch options may be enabled.

 

The default setting for the Single LED on the controller board is as a transmit indicator that can be controlled from DrzTrack or the F1EHN program.  If you do not want to use it for this, you may disable that usage and select one or more of the other possible usages.

You may use it to show when the antennas are being jogged, to blink when the Zero Index pulse on incremental encoders is passed, or to light up when the movement timer fails and stops the antennas.  Click the Send button to send these values to the controller.

If you have not used the Send to Controller button, the Cancel button abandons any changes you may have made in the configuration window, and returns you to the main setup window.

Tracking with other Programs
DrzTrack directly controls the CT-2 board to provide tracking of Moon and Sun.  There are two ways that other programs may interact with the CT-2 controller board.  One is via direct serial communication from the tracking program to the controller.  The F1EHN, MoonSked, and EME2008 programs use only the serial mode.  The TrakSM program can use serial mode when they it is configured for the NovaComm or EasyComm modes.  TrakSM may also be used in the DDE mode; Nova and SatScape can only be used in DDE mode.

DDE stands for "Dynamic Data Exchange", and is a method for multiple programs running on the same computer to communicate with each other.  A tracking program that uses DDE is said to be a DDE server and it sends tracking information to another program via DDE.  The DrzTrack program is a DDE client and can receive this tracking information and then relay it to the CT-2 controller board via the serial port interface.  When DrzTrack is functioning in this manner, the Tracking section of it's screen will show the name of the body or satellite being tracked, and the current position of that body as determined by the DDE messages from the tracking program.  In this mode, the actual tracking program (Nova, SatScape or TrakSM) may be minimized on your computer screen and the DrzTrack screen will show both the current satellite position and current antenna position.

When DDE tracking is started. tracking will be stopped, requiring you to click the 'Start Tracking' button to start moving the antenna.  This is a safety feature so the antenna does not start moving until you can see it happening on the DrzTrack screen

If you are using a tracking program that directly communicates with the CT-2 controller via the serial port, you must set up DrzTrack to use that program.  Then the program can be run right from DrzTrack. When you end the tracking program you will automatically return to the DrzTrack program where you can test or reset calibration if necessary. This saves a lot of switching back and forth between programs.  When running one of the DDE trackers it is necessary to run it from DrzTrack so that both are operational at once.

The Run button in title section of the tracking box in the main DrzTrack shows the name of the tracking program being used.  Initially this will always be DrzTrack itself, you must specify any other tracking programs you wish to use and where they are located on your computer, and what the interface method is.  If no external tracking program is specified then the Run button will not be shown.

Third party tracking programs are set up in theSetup menu, 'Program Options' selection, in the Programs tab. Here you will see a list of all programs that you have already set up.

 

Click the 'New Program' button to add a new program.

To edit an existing program name or settings, left-click the program name in the list.

Once one or more programs have been added to the list, you can select the one that you want to currently use with the drop down box at the lower right.  This is the program that will be assigned to the 'Run' button in the main dialog.

 

When the 'Add Program' is clicked, or you left-click a program name to edit it, this dialog box will appear.

 

First enter the name that you wish to identify the program by.  Then enter the full path and file name, or browse to the location of the program. If you browse to the file, you can double click on the file or single click and then use the OK button.

You can enter a command to be passed to the program on the command line if the program supports it.  In this example you see the custom data file being passed to the F1EHN program.

Next select the data format that the program uses, then click the Save button.

All of this information will be saved and remembered whenever DrzTrack is restarted.

 

 

Program Setup

This is the first tab of the Program Options dialog.  Here you select the Com Port and baud rate that you will use to communicate with the controller.  The Serial Ports drop down box will only show ports that are found on your computer.  If the port you want is not shown then it is not configured or not working.

The default baud rate for the CT-2 is 9600 baud.  It can be changed with on board switch settings, but there is little value to higher rates.  The system works very well at the 9600 baud rate.

The Box labeled "Path to Call3.txt" is initially set to ".\".  That means the program will look for the call3.txt file in the DrzTrack installation folder.  But it is helpful to use the same copy of call3.txt as other programs, such as WSJT, do.  That way when you add an entry in one program it will be available to the other programs too.  So you can change where DrzTrack looks for the file by entering the correct path.  You can also use the ::: button to browse for the location you want.  In the screen shot you can see what the WSJT-X path to call3.txt is on my system.

There are 6 check boxes to enable or disable program features.  They are described below.

The right side of the window is for configuring the display and usage of the signal or antenna polarization on the main DrzTrack dialog.  See the Antenna Polarization Settings page.


Here is the detail on setting up the feature check boxes in the Program Options dialog, first tab.

1. Fast Boot.  When checked, the display of boot messages in the main dialog, and on the LCD display (if present) is greatly speeded up.
2. Disable Auto Fast Boot. When not checked, the Fast Boot box will automatically be checked after the first slow boot messages appear.
3. Show offset position on LCD.  See Positional Offsets this page for information on this box.
4. Disable Move on Click. When checked moving the mouse cursor over the compasses in the main dialog will not show the position in the compass.  Also the 'Move on Click' check box in the main dialog will be disabled.  (For normal EME operation use of the mouse to show or set position is unlikely to be useful, and may be distracting.)
5. Show Go Buttons. This causes the Go buttons and fields on the main dialog to be shown.  They are used to manually move the antenna.

6. Show Offset Buttons. This allows buttons for quickly setting tracking offsets to be shown on the main dialog.  This feature is initially disabled by default. See Band Offsets below for more information.

Note: For information on the Programs tab of the Program Options dialog, see Tracking with other Programs, on this page.

 

Band Offsets
The right side of the Position and Band Offsets dialog box (shown below) can be used to set tracking offsets for each band of operation.  This is useful in situations where you may have multiple feeds or antennas on the same mount, and they do not all point exactly in the same direction.  For example if your 432 MHz feed is mounted beside your 1296 feed, it might cause the radiation pattern to be shifted by 5 or 6 degrees to one side or the other.  In that case you can set the offset value for the 432 band and the antenna will automatically be adjusted to track properly when you select that band on the main dialog.  When you have an offset applied, the compasses in the main dialog will show the radiation direction in black numerals, but the un-adjusted antenna mount position will be shown in red numbers.  (See the picture below.)

You can also specify a scheduling sequence for each band.  That only affects the transmit / receive periods shown on the clock portion of the main dialog.
 


Starting with DrzTrack version 5.12, you can also set band offsets from the main dialog, using the two Offset buttons below the compasses.  (See item number 6 in the features information above.)  When the "Show Offsets" checkbox is enabled then the offset buttons will be shown in the main dialog as shown here.  When you know that the antenna is correctly positioned you can click either button to automatically apply an offset for the current band.  You will get a warning box, telling you what offset value you are about to apply.  If you confirm then the offset will be applied and saved.

 

Positional Offsets
The left hand side of the dialog is where you can set up what I call 'Positional Offsets'.  This is for when there is some anomaly in the rotation of your antenna, for either Azimuth or Elevation.  Consider what happens if the gear or pulley that drives your Azimuth encoder is not mounted at the exact center of rotation of the antenna mount.  This will cause slight variations in the encoder output value as the antenna is turned.  Normally these variations are very small and can be ignored, but when operating on a high microwave band with a large dish antenna, even a few tenths of a degree error can cause loss of signal.  A similar problem exists when the antenna mount is not perfectly aligned with the surface of the earth.  This means that the rotating mast will tilted a slight amount in some direction.  When the antenna rotates the tilt will cause the beam to be low in some directions and high in others.

Another example is that the potentiometer or other encoder you are using exhibits some non-linear characteristics.  For example, when the antenna is horizontal, the reading is correct, but as you elevate the antenna the reading becomes more and more in error.

Positional Offsets are designed to adjust for such anomalies.  It is complicated to think about how this works, and often two people discussing it find that they both are saying something different but meaning the same thing.  So it is impossible for me to design a system that will be the way every person thinks.  Instead I have picked a scheme and provided several ways to enter, or measure and enter the offsets.  I hope this explanation will make sense to most of you.

Positional Offsets use data tables that are entered by the operator and saved on the computer (not in the controller).  The saved data contains values for various points in the rotation or elevation of the antenna.  Each point contains the number of degrees for the point and the offset at that point.  The DrzTrack program will interpolate between these points to determine the correct offset to apply at any given antenna position.  Any fixed band offsets will also be added at the same time, so the total offset will be Band Offset + Position Offset.

For Azimuth the first point must be at zero degrees and the last position must be 360 degrees.  For Elevation the start and end are at zero and 90 degrees.  All points in the table are at even numbered degrees (fractional degree values will be rounded). A point may be entered for each degree in the range 0-360 or 0-90, however in practice no more that 4 or 5 points should be needed because the program interpolates between points and usually the offset change will be linear, or fairly linear over a quarter turn.

Once the table is created and saved (by pressing Apply or OK), it must be enabled before it will be used.  Check the box 'Enable this List' to start using the offset table.

Ok, now that you understand the tables, here is how to enter them.  There are three methods:

1) Probably the simplest way is to click the little + button just below each table.  This will bring up a window where you can enter a position and offset.  It is not necessary to enter the positions in any special order, they will be added to the table in order by degree.  This method can only be used if you already know what your antenna offset is at the various positions.

2) You can rotate your antenna to each position and then measure the offset.  When you use this method you then enter the measured offset in the 'Offset' field below the table and then click the 'Set' button.  This adds the point and current position to the table.

3) Measuring the offset may be difficult.  You can try to bore sight it against a known object such as the Sun or Moon, but it is easier to use method 3, where the offset is automatically calculated for you.  To the right of the two tables is a check box labeled 'Auto-Calculate Offsets'.  When that box is checked the difference between the position that the encoder measures and the current position of the antenna will be shown.  By rotating the antenna so it is pointed at the Sun or Moon, either by observation, or possibly by measuring Sun or Moon noise, the actual offset will be displayed in the Offset field and you can simply click the Set button to save it.  Of course this method requires that you measure when the Sun or Moon is at various positions in the rotation of the antenna and so might take days to accomplish.  However as each new offset value is added to the table the aiming will become more accurate, so you can enter one or two points and then add more points as they are encountered.

When using method 3 very precise positioning of the antenna is required, so I have provided a way to 'Jog' the antenna by small amounts to get it correctly placed.  To jog the antenna you click one of the four arrow buttons.  Each click turns on the motor for a short time.  The time the motor is on is controlled by the 'Position Adjustment Increment' drop down box.  The choices are 2, 1, 1/2, and 1/10 of a second.  Of course if you have switches to manually control your antenna you can use those instead.

Be sure to enable your tables.  When  you are done, click OK and return to the main window.  Now the offset position will be shown on the compass in black numerals and the actual antenna position as measured by the encoders will be shown in red numerals.

Also note that the LCD display on the encoder will continue to display the exact readout from the encoders, and will not include either positional or band offsets.  There is a checkbox in the 'General' tab of the Setup dialog that can be used to cause the LCD to display the offset position rather that the encoder position. See the above description of feature checkboxes.

 
 
Absolute Encoder Programming

For DrzTrack version 5.10 and later, the absolute encoder programming window has been moved from the setup dialog to the calibrate dialog.  So if an absolute encoder is specified for elevation or for azimuth, the corresponding calibrate dialog will show a button labeled "Absolute Encoder Programming".  (See below for information on previous DrzTrack versions.)

 Clicking the button will bring up this dialog:

When this window is opened, production data is read from the encoder and displayed in the center fields.  When you select (click) an encoder shown in the middle list the current values for that encoder will be shown in the set fields below.  Then you can change any of them and click the corresponding set button.  The new value will be sent to the encoder and then the encoder settings will be re-read and displayed.

You may configure the direction, address, and resolution as you require.  The address is the value you are most likely to need to change.  As shipped most encoders are set to address 0. The address has to be changed to 1 for use as an azimuth encoder.  If you have two encoders set to the same address (0) then you must connect only one of them and change it's address before connecting both.

Low resolution for US Digital absolute encoders gives .1 degree resolution. High resolution may be used if you require .01 degree position accuracy.  Note that each encoder may be set for low or high resolution separately.  The program detects the setting directly from the encoder and does not require a switch setting (as the previous versions did).

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