With this circuit you can produce the sound effect passing from one channel to another. The circuit is from Mullard documentation from the 1960s. The transistors may be the BC548.
The output voltage is adjusted by the trimpot. The power transistor mist be mounted on a heatsink. The 3.9...
Originally, this circuit is from an English magazine, but I found it in Argentina's Radio Chassis...
The previously mentioned versions of monostable multivibrators in this section are not...