Found in a 90’s Popular Electronics, this circuit uses two CMOS inverters to generate a signal of a few hundred hertz determined by C1 and the R3 setting.
This alarm circuit was found in the July 1992 Radio Electronics magazine. The circuit uses a small...
Found in a Philips publication from the 1970s, this circuit uses a DO040, which is difficult to obtain...
This simple nicad battery charger uses a current regulator with the LM350. This integrated circuit must be...