Suggested by Philips documentation from 1968, this circuit uses components from the era that can be replaced by modern equivalent types. The double transistor can be replaced by a matched pair.
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...