The presented circuit makes use of a common operational amplifier that must be powered by a symmetrical source. R resistors from 10k to 1M determine the gain and compression of the signal.
This circuit can generate signals from 2 to 15 MHz or 4 to 22 MHz depending on the used components...
This circuit was found in an old French documentation, but it is current if we use the BC547 for...
Small variations in the resistance of the skin of a person holding the electrodes can be detected by...