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RFI (Radio Frequency Interference) Sleuthing with the TinySA (2021)
Although focused on the use of the TinySA, the techniques and equipment described in this article may be applied to using any other type of ...
Click on the image for a larger version The reason for this specification of a "clean" ground and being placed outside, in the clear is that this antenna - being a tiny fraction of a wavelength on the highest frequency for which it is to be used - is essentially a capacitor that couples into the " æ ther"(e.g. free space). Click on the image for a larger version Unlike the active whip, this antenna can be entirely "self contained" in the sense that the amount of energy impinging on the loop that is being conveyed to the receiving device and the cable itself has little effect on this level. Optional enhancements to this device would be a diode(D201) to protect against accidental reverse-polarity application to the antenna and an LED to show that power is turned on(LED201) with its current intentionally set low(e.g. a 10k limiting resistor for about 1mA) to minimize battery drain.
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