Modifica di Electromyography (sezione)

====Electronic Noise from the Amplifier====
An unavoidable source of noise is the one intrinsically present in the electronic circuits used for amplifying and conditioning the sEMG signal. This noise has frequencies ranging from direct current (0 Hz) to tens of kHz. To minimize this noise, state-of-the-art amplifier design techniques and high-quality electronic components must be used.

''Electromagnetic Environmental Noise''

Another highly annoying source of noise is environmental noise, originating from electromagnetic radiation (radio, television, cell phones, power distribution lines, electrical and electronic devices, etc.) that continuously inundates the human body when it is in modern urban environments. More accurately, this should be referred to as interference. The most significant type is the so-called 50 Hz noise (60 Hz in the American continent and Japan), caused by electromagnetic emissions from power lines. The 50 Hz noise, also known as "mains hum" or "alternating current hum," is particularly disturbing because it often reaches levels that are 100 to 1,000 times higher than the sEMG signal itself. The fight against mains hum is carried out in various ways, including the design of appropriate amplifiers to minimize the recording of 50 Hz noise, proper electrode placement techniques, and, finally, conducting the recording in specially shielded rooms (Faraday cages).