This shortwave preselector was found in the July 1994 issue of Radio Electronics magazine. The circuit is suitable for telescopic antennas, matching the impedance with the receiver used.
In the figure we have a typical polarization circuit for MOSFETs with a high impedance...
This circuit was found in a 1969 EEE. The circuit uses transistors from the era that can be...
In the figure we have an interesting protection bridge against power polarity inversion of a...