To modulate or not to modulate....

That radio it seems has made a come back. My life hasn't spanned long enough nor did it begin back during the time when radio transmission was supposed to be the next big thing, for me to be able to see radio communication evolve. However, with whatever little I have seen I believe that radio has made a comeback; and how. I'm talking about the use of radio for entertainment purposes and news broadcasts because it never really went out of favour in transportation, and it never will.

What started out as simple AM or Amplitude Modulation, it has now evolved into a diaspora of techniques of getting the information across to the receiver. Pulse modulation, phase modulation, width modulation, frequency modulation (modulation modulation?!) are a few more methods in use.

The inherent problem that led to the decline in popularity of the radio was the "noise" that normally accompanied the transmission. You couldn't enjoy Beethoven without the flies buzzing in your ear. Nor would a sport telecast be complete without an apparent presence of a swarm of bees. No doubt the advent of other better communication channels in the Television and more lately, the Internet had a humongous role to play as well.

The reason I say that the radio has made a come back is because the newer FM (frequency modulation) stations seem to be popping up like mushrooms all over the place. The reason being that FM suffers a lot less from noise, which is a great advantage when the transmission needs to carry high fidelity stereophonic sound. The flip side of it is that FM has limited range in comparison to the earlier AM stations. The FM stations lie within the radio spectrum of 88 Mhz through 108 MHz.

Worth pointing out here is that, though utilizing frequencies within 118Mhz through 136Mhz, VHF aircraft communication employs amplitude modulation of its messages. The reasons being the lower bandwidth requirement, thereby a lot more channels can be accommodated with a given range of frequencies. Since the transmission is mainly voice, the requirement for high fidelity is not as important as in case of music.