Found in 90s Popular Electronics, this circuit uses common general-purpose transistors in a configuration that has been extensively explored on this site and in our articles.
An oscillator that uses two gates is not suitable for critical applications, as it tends to pick...
The integrated circuit used in this amplifier is not very common today. This amplifier was found in...
This 1992 circuit uses a common LM139 comparator today, but it can be built with equivalent...