100 Hz Second Order High Pass Filter (CB25815E)

This filter with the 741 op amp was found in the February 1995 Electronics Now magazine. The power supply must be dual.

Blown Fuse Alarm (CB4875E)
This 3V-only circuit was found in old American documentation, but can be implemented with...
Variable Regulator 0 to 1 A (CB1195E)
The output voltage of this circuit, which can regulate the current in a load between 0 and 1 A,...
Temperature compensator for VFO (CB8096E)
This circuit was found in a Popular Electronics from the 90s. The circuit has temperature...