We found this circuit in a documentation for radio amateurs from the 70s. The transistors can be the BC548. With it, small speakers of 4 or 8 ohms can be used as microphones.
August 2017 - The PIC32MM microcontrollers of the Microchip 32-Bit Family can be obtained from...
The purpose of this circuit is to modify the sound of organs so that they resemble the sound of a...
This circuit was found in the August 1992 issue of Radio Electronics magazine. The circuit can be...