In the last section, we saw how a very simple transmitter worked. It was made up of several different types of electronic components, including capacitors, transistors, resistors, etc.
Without going into complete details of how a semiconductor works, there are certain things we must know about them in order to use them. Semiconductors are chemical elements, that when compounded with other elements, have certain electrical characteristics.
Recall that in a semiconductor diode, we have 2 regions of DOPED semiconductive material. One region is doped positive, and the other region is doped negative.
Before going into the specifics of how a Klystron tube works, we must first understand it’s basic parts. Which reminds me of a story….
I once had an “oldtimer” friend tell me that he once had to build a dummy load for a radar unit.
Thomas Edison, famous (at least in America), for inventing the light bulb, made many discoveries before he completed his task of lighting the path of the world.
Now that we have caught up on basic tube theory, and understand how a beam of electrons can be formed in a vacuum, we are well on our way to understanding how a KLYSTRON operates.
Another important factor when dealing with klystrons is heat. Not all of the developed in the cathode becomes radiated output. Much of the energy is dissipated as heat. If the tube gets too hot, it can become a hazard to itself. Temperature sensors are placed in various places to shut down the tube in the event of overheating.
Radio is very widely used in everyday life now, and it is becoming more widely used as new applications are being found all the time. One of the original terms for radio was wireless, end even today many people refer to a radio as a wireless set.
Radio waves are one form of electromagnetic radiation. They have the lowest frequency, and hence the longest wavelengths. Above the radio spectrum, other forms of radiation can be found.
