Found in a 1988s Radio Electronics, this circuit uses transistors of general use to increase the intensity of signals up to about 30 MHz. The power can be done by battery because the consumption is low.
This one-digit photometer using CMOS circuits was found in a 1989 documentation. The circuit is...
This circuit can function as a simple shield converter from BCD to analog outputs. The circuit...
In the figure we have a different configuration for an oscillator with the 555. This circuit was...