This fader or fader was found in a 90s Popular Electronics. The circuit uses transistors that are equivalent to BC548. Input and output cables must be shielded.
In the original 1992 application, this passive circuit was intended for use in the car. At that...
In the figure we have the way of obtaining 220 V from two equal 110 V transformers or 230 V from...
This antenna for the frequencies 146 or 440 MHz was found in a magazine 73 for Amateur Radio of...