Found on an 80's Elektor, this circuit uses common components, being the diode a general purpose germanium. The coils select the frequency range of the indicator that reaches 60 MHz.
This very low frequency amplifier has a gain of 1,000 and was found in a 1967 documentation. The circuit is...
April 2017 - Mouser Electronics has the bq25890H integrated circuit consisting of a single 5 A...
This circuit was obtained in an old US 1974 documentation when Nixie tube displays were common. The...