Found in a 90s Hands On Electronics, this small preamp finds applications like microphones and other sources. Its gain is 3 dB with a response of 120 to 20 000 Hz.
This circuit is from the 1977 GE semiconductor manual. The components used are uncommon today....
This circuit has 4 operating modes and was found in the 1995 Encyclopedia of Electronic Circuits...
The voltage of 30 V indicated in this project, shown in the figure, depends on the diac used. It...