Antenna Control Project
Antenna Control
Version Display
This project is to construct an electronic device that will allow the operator of an Amateur radio station to select one of three radios (transceivers) and then to connect the selected radio to one of three antennas. In addition to this flexibility the operator can monitor the antenna by using a built in SWR (standing wave ratio) monitor that will display in a digital format, or as a bar graph. The control unit will also monitor the RF power to the antenna and when this occurs will activate an 'on air' display.
The project uses an Arduino Hero/Uno (micro computer) for monitoring all functions. A single push button will allow selection of all displays.
The first screen is displayed during the power up sequence and displays the current version and date. This will change to the main operating display after the software download is complete.
Here is a video of this project: https://www.youtube.com/watch?v=cB5vaPb_D0o&fbclid=IwAR2whotSJM4FW-J5wX6oxbeKiXfuKKzfEvksvNzsSnvQFl0hZjoCmyaRs88
Version Display
This project is to construct an electronic device that will allow the operator of an Amateur radio station to select one of three radios (transceivers) and then to connect the selected radio to one of three antennas. In addition to this flexibility the operator can monitor the antenna by using a built in SWR (standing wave ratio) monitor that will display in a digital format, or as a bar graph. The control unit will also monitor the RF power to the antenna and when this occurs will activate an 'on air' display.
The project uses an Arduino Hero/Uno (micro computer) for monitoring all functions. A single push button will allow selection of all displays.
The first screen is displayed during the power up sequence and displays the current version and date. This will change to the main operating display after the software download is complete.
Here is a video of this project: https://www.youtube.com/watch?v=cB5vaPb_D0o&fbclid=IwAR2whotSJM4FW-J5wX6oxbeKiXfuKKzfEvksvNzsSnvQFl0hZjoCmyaRs88
Main Display
The main operating screen displays the operators station ham call sign. As shown this is 'W1MBS'. Located on the second line is the station location "Greensboro'.
On the display lower left corner is the radio being selected. Show is 'XTR 2' for radio 2 connected to the antenna. On the lower right is the display for the antenna selected, in this case 'ANT 2'.
The main screen displays radio 2 is connected to antenna 2. If the power is lost to this control system, or if the micro computer fails, the current radio to antenna connection will stay connected.
Main Display
The main operating screen displays the operators station ham call sign. As shown this is 'W1MBS'. Located on the second line is the station location "Greensboro'.
On the display lower left corner is the radio being selected. Show is 'XTR 2' for radio 2 connected to the antenna. On the lower right is the display for the antenna selected, in this case 'ANT 2'.
The main screen displays radio 2 is connected to antenna 2. If the power is lost to this control system, or if the micro computer fails, the current radio to antenna connection will stay connected.
SWR Display
By pressing the 'mode' push button on the front panel the operator can change operating modes and associated screen displays. The screen shown is the 'SWR' display. This shows the relation between transmitted power and the reflected power from an antenna. As shown the current SWR is 1:1.67. This SWR is shown in the top right corner as a numerical value, and then displayed by a bar graph.
The formula is
SWR = ((forward) + (reflected)) / ((forward) - (reflected))
Any adjustments to either the radio of by a tuning unit will be shown on this screen.
By pressing the 'mode' push button on the front panel the operator can change operating modes and associated screen displays. The screen shown is the 'SWR' display. This shows the relation between transmitted power and the reflected power from an antenna. As shown the current SWR is 1:1.67. This SWR is shown in the top right corner as a numerical value, and then displayed by a bar graph.
The formula is
SWR = ((forward) + (reflected)) / ((forward) - (reflected))
Any adjustments to either the radio of by a tuning unit will be shown on this screen.
On Air
When the antenna control senses an RF source the unit will display the 'ON AIR' screen. The system can detect SSB, CW, or an AM signal. After the transmitted power is removed the display will return to the 'main' display to show antenna and radio connections.
When the antenna control senses an RF source the unit will display the 'ON AIR' screen. The system can detect SSB, CW, or an AM signal. After the transmitted power is removed the display will return to the 'main' display to show antenna and radio connections.
Mode Display - Function
This screen is shown by pressing the 'Mode' switch on the front panel. By repeated pushing the button the cursor on the left side will move from mode items one at a time with each press of the button.
If the button is not pushed for 5 seconds the computer will select the requested mode and display that correct screen.
This screen is shown by pressing the 'Mode' switch on the front panel. By repeated pushing the button the cursor on the left side will move from mode items one at a time with each press of the button.
If the button is not pushed for 5 seconds the computer will select the requested mode and display that correct screen.
Calibration Display
The monitoring of the radio and antenna connection is accomplished by a resistor network. The network can be checked by the calibration display. As shown in the top right corner radio 2 is connected to antenna 2. The network resistors for the radio switch is 542, and the resistance for the antenna is 491. The micro computer will calculate these values and display the correct data.
The monitoring of the radio and antenna connection is accomplished by a resistor network. The network can be checked by the calibration display. As shown in the top right corner radio 2 is connected to antenna 2. The network resistors for the radio switch is 542, and the resistance for the antenna is 491. The micro computer will calculate these values and display the correct data.
RF Level Display
With this display the operator can adjust the input RF power from the transmitting equipment. When the power level is set to '10' the antenna control unit is calibrated for correct operation.
With this display the operator can adjust the input RF power from the transmitting equipment. When the power level is set to '10' the antenna control unit is calibrated for correct operation.
Microcomputer
Shown is the test breadboard for the Arduino Hero/Uno computer used in the antenna control unit.
The knob/potentiometers, lower left corner, are used to simulate the resistive network on the radio and the antenna switches. The 'blue' push button in the lower right corner is the mode (function) switch that will be mounted on the front panel. And the 'red' button is to test the action of the RF energy to activate the 'on air' screen. This red button is for test only.
Only the LCD display and the micro computer are used in the antenna control system, the breadboard is only used for programming and testing. The USB cable allows for software upgrades and station programming.
Here is a quick video link to show this in operation: https://www.youtube.com/watch?v=cB5vaPb_D0o&fbclid=IwAR2whotSJM4FW-J5wX6oxbeKiXfuKKzfEvksvNzsSnvQFl0hZjoCmyaRs88
Shown is the test breadboard for the Arduino Hero/Uno computer used in the antenna control unit.
The knob/potentiometers, lower left corner, are used to simulate the resistive network on the radio and the antenna switches. The 'blue' push button in the lower right corner is the mode (function) switch that will be mounted on the front panel. And the 'red' button is to test the action of the RF energy to activate the 'on air' screen. This red button is for test only.
Only the LCD display and the micro computer are used in the antenna control system, the breadboard is only used for programming and testing. The USB cable allows for software upgrades and station programming.
Here is a quick video link to show this in operation: https://www.youtube.com/watch?v=cB5vaPb_D0o&fbclid=IwAR2whotSJM4FW-J5wX6oxbeKiXfuKKzfEvksvNzsSnvQFl0hZjoCmyaRs88
Switching Control
Both the radio selection and the antenna selection are controlled by high quality ceramic rotary switches. The resistive network for each switch uses 5% tolerance resistors for accuracy, and the software allows for any errors. These switches are capable of handling up to 350 watts of RF energy.
Both the radio selection and the antenna selection are controlled by high quality ceramic rotary switches. The resistive network for each switch uses 5% tolerance resistors for accuracy, and the software allows for any errors. These switches are capable of handling up to 350 watts of RF energy.
Basic Concept of Antenna Control Project
This is the basic schematic of the antenna control. There are two rotary switches that control the path of the RF from the radio to the antenna.
Each radio can be selected to each antenna. Associated with each switch is a resistive network that provides a voltage difference to the UNO. This is calculated to display the radio and the antenna selected. A push button 'mode' switch is used to change the display screens. Between the radio and the antenna switch is a SWR bridge. This provides voltage for 1) forward voltage, 2) reflected voltage, 3) a voltage to activate the 'on air' display, and 4) a reference calibration RF level.
*Not shown are the by pass capacitors, the directional diodes, limiting resistors, or the power supply. The correct value of each component will be added after construction and calibration.
This is the basic schematic of the antenna control. There are two rotary switches that control the path of the RF from the radio to the antenna.
Each radio can be selected to each antenna. Associated with each switch is a resistive network that provides a voltage difference to the UNO. This is calculated to display the radio and the antenna selected. A push button 'mode' switch is used to change the display screens. Between the radio and the antenna switch is a SWR bridge. This provides voltage for 1) forward voltage, 2) reflected voltage, 3) a voltage to activate the 'on air' display, and 4) a reference calibration RF level.
*Not shown are the by pass capacitors, the directional diodes, limiting resistors, or the power supply. The correct value of each component will be added after construction and calibration.
