Turn off a TV in style By Jacob McKenzie
This TV-B-Gone uses a 9V battery to send its signal through a matrix of 20 infrared (IR) LEDS. This extends the working range of the device to about 90 feet (line of sight). Using this in a regular-sized room, you are pretty much guaranteed to zap the TV no matter where you point it.
1. Get the stuff
You won’t need much to build this; here is a list of the materials shown in Figure B.
TV-B-Gone (keychain version)
one 2N3904 Transistor (if you have any transistors ...