Scale Expander for 12V Meter (CB21330E)

This circuit was found in a QST from the 1990s. The circuit expands the scale of a 10V instrument to measure 20V.

MOSFETs bias (CB6962E)
In the figure we have a typical polarization circuit for MOSFETs with a high impedance...
Graphic Equalizer (CB24554E)
This equalizer was found in the May 1978 issue of Radio Electronics magazine. The component values...
Colpitts Harmonic Oscillator (CB9645E)
Found in a 1980s American documentation, this crystal-controlled oscillator generates 100 MHz...