The purpose of replacing galvanometers with electrodes impedances is to measure the electrical signal from the body more accurately and with less interference. Galvanometers can introduce noise and distortions into the signal, while electrodes impedances provide a more direct and precise measurement.
Electrodes impedances work by measuring the resistance and capacitance at the interface between the electrode and the skin. This information is then used to calculate the impedance, or opposition to the flow of electrical current, in the circuit. The lower the impedance, the better the signal quality and accuracy of the measurement.
One of the main advantages of using electrodes impedances is the reduction of noise and interference in the measured signal. This leads to a more accurate and reliable measurement. Additionally, electrodes impedances are non-invasive and do not require direct contact with the body, making them more comfortable for the patient.
While electrodes impedances offer many benefits, they do have some limitations. They can be affected by sweat, skin oils, and movement of the electrodes, which can change the impedance values. Additionally, electrodes impedances may not work well for all types of measurements, such as those involving high frequencies or very small signals.
To optimize electrodes impedances for better measurements, it is important to properly prepare the skin before placing the electrodes. This may involve cleaning the skin, removing hair, and applying a conductive gel. It is also important to regularly check and adjust the electrodes to ensure they have good contact with the skin and maintain a low impedance.