This low noise microphone preamplifier circuit was found in American documentation from the 90s. The circuit requires special care with the layout. The power can be between 9 and 18 V.
The gain for this circuit is given by the ratio between R2 and R1. The circuit is suggested by...
This circuit is based on an operational amplifier that is uncommon today, but that can reach the...
We found this circuit in a Popular Electronics of the 90s. The circuit uses a touch sensor formed by...