This circuit was found in 80's Popular Electronics. The components used are common and the number of indication channels (LEDs) can be changed.
We show an oscillator that produces rectangular TTL signals based on inverters. Inverters can also be...
We found this circuit in the March 1995 issue of Electronics Now magazine. The circuit has a...
This circuit, with an operational amplifier, was found in the Motorola Dataar Linear of 1990. The...