We found this preamplifier with 70 dB gain for microphones in American documentation from the 90's. Consumption is low and equivalent transistors can be used.
This circuit from a 1980 publication, converts the temperature sensed by Q1 into a frequency in a...
This oscillator has its frequency controlled by crystal and its frequency can be between 100 kHz...
The author has many books he had written in Eglish (See the Biography) published by famous...