This circuit is from a Popular Electronics from the 90s, consisting of a repeater relay for remote control of TV, which today can be done by Wi-Fi or other simpler resources.
This oscillator uses a small transistor amplifier or radio output transformer. We found it in a...
This small transmitter circuit has a range of about 100 meters, and the antenna must be connected to...
In the figure we have the way to connect several 555 to obtain sequential operation. The component...