Using components of the time, this 3 and half digit scale was found in an Electronics Now from the 90s. The circuit is powered by a 9 V battery.
If we modulate a beam of light from an LED, for example, we can receive this beam of light at a...
This circuit is from a publication of the 70s, but it can be easily assembled with the BC548. The...
In the circuit in the figure, when a pulse of light falls on the LDR, the circuit arms with the...