5 LED Log Scale with U257B (CB25442E)

The circuit was found in the February 1992 Radio Electronics magazine. The scale can be changed by changing R2 and R3.

Power Outage Alarm (CB5952E)
We found this circuit very simple in an old documentation. The relay is high voltage sensitive, but...
Sinusoidal Oscillator (CB9189E)
This circuit was found in an Elektor from the 90s. The circuit uses common components even today,...
Monostable (CB16309E)
The circuit, shown in figure 2, is a monostable multivibrator with two NAND ports out of the 4...