Introduction:
For
our project, we designed a wireless keyboard that uses RF to transmit signals
to the computer. In our design, we use a
regular, 102 key ps/2 keyboard and connect it to our transmitter circuit. On the computers side, we connect our receiver
circuit to the ps/2 port on the back of the computer. With this set up, we convert a cheap ordinary
keyboard into a wireless keyboard.
We
had several motives for choosing this project.
First of all, computers have lots of wires and cables connected to
them. These include the power cable, the
monitor cable, the printer cable, network cable, speaker wire, microphone
input, modem lines, various USB device and the essential mouse and keyboard
wires. These wires form an unsightly
tangled mess in the back of all computers.
We therefore chose to eliminate one of these wires by making a wireless
keyboard. Second, the trend for making
wireless devices continues to increase. These
days, we have wireless remote controls for TVs, VCRs, stereo systems, car alarms
and garage door openers. Furthermore, we have wireless telephones, network
connections and the now ubiquitous cell phones.
We even have wireless remote controls for floor fans. Since wireless devices are becoming so
popular, we decided to make a wireless device so that we could learn more about
such devices. Furthermore, we decided to
make a wireless keyboard because current wireless keyboards are either too expensive
or have a fairly short range. For
example, most current wireless keyboards use infrared for communication, which
limits their range to about 6ft. These
keyboards cost about $40. Some newer
keyboards that use RF have a longer range, but these keyboards often cost twice
as much or more. Finally, we had a need
for a cheap wireless keyboard with a long range: Sean enjoys playing movies on his computer
but watching them on his TV. To do this,
he runs a long wire from his video card to the TV. However, if he wants to pause or rewind the
movie, he needs to get up and go to his computer’s keyboard and hit the
appropriate buttons. Although he has an
infrared wireless keyboard, the range is only about 6 feet, which is too short
a distance for him. So, being electrical
engineers, we decided to make a cheap wireless keyboard with a longer range.