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.
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...