I’m unsure what you mean by “sound receptors.” If you refer to a device that can detect an RFID transponder implanted within the human body, then such a transponder does not make noise. Rather, it receives energy from a reader and reflects back electromagnetic waves that can be deciphered by the appropriate interrogator.
To detect a transponder, one needs to know the frequency and protocol used. Implantable transponders usually operate at 134 kHz and comply with the ISO 11784 air-interface protocol standard. Doowa, Omnikey, Tectus and others manufacture readers that would fit the bill and should be relatively easy to operate.
—Mark Roberti, Founder and Editor, RFID Journal
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