This circuit was found in 80's Popular Electronics. The components used are common and the number of indication channels (LEDs) can be changed.
Found on an 80's Elektor, this circuit uses common components, being the diode a general purpose...
This 1.6 GHz oscillator with 40 mW of output power was found in a Popular Electronics from...
Found in a 90’s Popular Electronics, this circuit uses two CMOS inverters to generate a signal of...