We found this circuit in a 1977 National Semiconductor Databook. The circuit can use other FETs like the BF245 and has an input impedance of 10 megohms. The circuit gain is unitary.
One 4018 is used to divide the frequency of a digital signal by ten as shown here. The maximum...
We found this circuit in the National Semiconductor Linear Applications Handbook of 1994. The...
This amplifier, from Philips Databook is suitable for automotive applications. The input...