We found this circuit in the December 1968 issue of Radio Electronics magazine. The circuit is used with high-impedance magnetic headphones. The transistors are from that time.
What this circuit does is change the logic level of a signal thus serving as a different logic...
This electronic flash circuit was found in the March 1961 Radio Electronics magazine. The circuit...
On this website we show how to calculate the components of this circuit for other frequencies. The basic...