In order to look at electric waves, you need to use a Cathode Ray Oscilloscope (CRO). A CRO works by building up
a large p.d. between the Cathode and Anode so that the
electrons in the cathode get very excited and jump off it towards the anode. Some of
these hit the anode and cause a current to flow. Others miss, and these continue to
travel passing a series of electrodes, the voltage of which is varied and this steers the
electrons. The p.d. on the electrodes is the signal that we wanted to look at.
The electrons collide with the fluorescent screen causing a spot of light to appear
where they hit. With a multitude of electrons, an image can be created.
In order to listen to electric waves, you need a speaker. This
is simply an arrangement of two magnets which repel and attract each other depending on
the current flowing and the amount of movement is affected by the voltage. One of
these is fixed in position and the other is attached to a paper cone which vibrates air