Introducing Secondary School Students to Telecommunications Engineering Through the WiFinder Project: Part I – Implementation of Handheld Device

Engineering workshop plays an essential role in the development of practical skills and knowledge. It serves as an experiential learning environment where theoretical concepts are transformed into real-world solutions through hands-on activities. The availability of proper tools is crucial in ensuring the effectiveness of the workshop. Creating an in-house radio source locator for the training program offers several significant advantages, such as a cost-effective solution, and customization of features to support intended lessons. This paper describes the design and implementation of an in-house radio direction finder utilizing WiFi technology in the 2.4 GHz band. The device employed an ESP32 embedded board with a touchscreen for the user interface and measurement display. The resulting finder was able to show the signal strength of the selected WiFi access point and its direction. The screen interface allowed users to scan and select the WiFi source in the receiving range. The radio direction finding device was powered by a Lithium-ion battery which was able to operate continuously for at least 1 hour. The firmware update was designed to support the over-the-air approach. The deliverables for the training workshop consisted of a radio direction-finding unit, an omnidirectional antenna, a directional antenna, a charger, a handle, and mounting kits. A user manual and related instructional videos were available online for all trainees. This in-house device met the designed features and served its original purposes, especially customization and costeffectiveness.