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<\/a><\/div><\/a><\/div><\/a><\/div><\/a><\/div><\/a><\/div><\/a><\/div><\/a><\/div><\/a><\/div> <\/div> <\/div><\/div>\n\n\n\nCommunication between the Raspberry Pi and the ESP32 is facilitated through a 2.4 GHz WiFi link in Access Point (AP) mode, suitable for field operations without the need for a router.<\/p>\n\n\n\n
For antenna tuning, two methods have been implemented. <\/p>\n\n\n\n
The first method allows manual tuning by entering the desired operating frequency via a keypad, providing flexibility and precision in frequency selection.<\/p>\n\n\n\n The second tuning method utilizes Bluetooth communication with an Icom IC-705 transceiver for semi-automatic tuning. <\/p>\n\n\n\n This method allows the control system to communicate with the transceiver to continuously optimize antenna settings based on the selected operating frequency, simplifying the tuning process during operations.<\/p>\n\n\n\n To switch between the transceiver (or receiver) and the VNA, an RF relay has been implemented.<\/p>\n\n\n\n This relay enables seamless switching between antenna operations for transmission or reception with the transceiver and antenna analysis with the VNA. <\/p>\n\n\n\n To enhance monitoring capabilities further, a small ESP32 cam is integrated for remote visual inspection of the vacuum capacitor positioning, providing real-time feedback during adjustments.<\/p>\n\n\n\n I am fully aware that this is a gadget with no real added value, but I found this camera in my junk box and thought it would be a good opportunity to use it, especially to manage it from a software point of view. <\/p>\n\n\n\n Likewise, the ESP32 unit was upgraded with a small OLED display providing basic information on the communication link, battery level, temperature, and humidity, which are obtained via an I2C DHT sensor.<\/p>\n\n\n\n The ESP32 unit installed on the antenna supporting structure is powered by means of a 22Volts RC model battery, complete with a minimum voltage detection system to protect it from total discharging.<\/p>\n\n\n\n Additionally, a WSPR (Weak Signal Propagation Reporter) reporting system is integrated to monitor and analyze signal reception from the antenna, providing insights into propagation conditions and antenna performance over time.<\/p>\n\n\n\n<\/figure>\n\n\n\n<\/figure>\n\n\n\n<\/a><\/div><\/a><\/div><\/a><\/div><\/a><\/div><\/a><\/div> <\/div> <\/div><\/div>\n\n\n\n