This circuit for the very low frequency range was found in the Radio Electronics magazine of February 1983. The components are according to the frequency range to be amplified.
Obtained from a 1967 documentation, this circuit uses transistors from the time. The galvanometer can be a...
Motors up to 2 A can be controlled by this circuit, which requires a symmetrical source. Although...
This sensitive MW receiver was found in a publication of year 1958., The circuit uses germanium...