The transmitter is designed to be powered with 5V DC, which could come from a mobile phone charger,
wall wart, or even four 1.5V batteries connected in series with a suitable low dropout regulator. Do not use
more than 6V: this may kill the microcontroller; the LCD may not work properly with more than 5V. Best
results will be obtained with a well-regulated and well-smoothed 5V supply.
2. Design
2
