This transistorized stage has a high gain, being adjusted by VR1. The circuit can be used as an excellent audio preamp. We found this circuit in a 1996 English publication.
In the figure we have a simple signal tracer circuit to be coupled to the volume control of an AM...
This circuit was found in documentation from the 90s, using components from that time. The...
This circuit, obtained from old documentation, allows the recovery of sulfated batteries. The...