This small signal amplifier circuit was found in Motorola's 1969 documentation. The FET and the transistor can be of any type and is battery powered since the consumption is very low.
In the figure we have an interesting protection bridge against power polarity inversion of a...
This amplifier was found in an old publication of 1990. With the changes, it may still be...
Obtained from an English publication, this circuit actually needs a current limiting resistor,...