This circuit covers the bands from 1.8 to 150 MHz, with plug-in coils whose characteristics are given next to the diagram. The FET can be a BF245. We found it in old documentation.
The circuit in the figure is a current regulator with adjustment in the range of 0 to 3 amps. The...
This filter with the operational 741 passes the frequency range between 300 Hz and 3,400 Hz. This...
Taken from an Electronics Now from the 90s, this circuit generates signals whose frequency depends on...