This simple digital circuit tester can work with TTL technology when powered by 5 V and with CMOS when powered by voltages from 3 to 15 V. The circuit provides LED indications and uses current ICs.
In the figure we have an ultrasound generator using a capacitive transducer that serves as a...
We found this circuit from a commercial megaphone in a Japanese publication in 1967. The circuit is...
This circuit was published in Radio Electronics magazine in June 1959. The circuit uses an...