Testing of antennas can be both simple and complex. At its simplest, testing involves sending messages from different locations and seeing which ones are received, and then comparing the results against other antennas. At the complex end, this can be using expensive test chambers and equipment to measure the signal strength, gain, and radiation patterns. However, it seems that a reasonable job can be done with cheaper methods.
📄️ Testing Reports
📄️ LoRa Antennas
The stock antennas provided with the T-Beam and other boards usually come from 'mixed bags'. They may not have been designed or tuned for your given frequency range, and they may not be of a quality design.
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