like this avoids the basic unit of the wave attributes each one of these is a cycle basically frequency is equal to the number of cycles but apparently unit time of sale a second away that looks like this has a much higher frequency than way it looks like this even though they have the same empty so now we understand what frequency an effort to demean we can use these concepts to transmit information the first wave i'm gonna tell you about how to do this is called amplitude modulation and this is what the and stands for and ham radio so this idea is that's the insides example to say i have some signal maybe too something or something else that some signal that i want to send you and that signal looks like this parasitism well just frickin means you'll see why it is in a second i want to draw a the negative simpson this is an auto sandy on and i want to send it to you by not remand cuevas what i do is i send you a way of a particular frequency i tell you to look for with that we can see it what i'm gonna do is i'm gonna send you this way where i changed the way over based on the signal that i want to send you sort of a signal is low i make the amplitude of myway lower the signals i make them part of my living so and here we have two distinct resistances signal and this way that i'm sending you was called the carrier with because it carries a signal sort of go that's all you have to do is yet to look at how big the waves at any given point and then you can get to know that transcended schemes called entered modulation and it's the one that's used and radios most often andrea statically to get you songs do you hear say car when you're driving us into the radio there's a hamas also ask them and you've probably guessed by now that sm means frequency modulation so frequency modulation is another way i can send information and of course we can we can use room to modulation in the same way that i used to have a tip modulation to send you some like it on file but well i'll talk about now is how say things like cell phones houston's modulation to send digital information and what i mean by that is itself on twice and to each other or to our list out the communique with them they want to send information forms of ones and zeros and later they transmit uh... some current cell phone translate those wanting to those into texas on to another uh... but to do that what we can submit as we can agree that if your cellphone in year zero freedoms it looks like this you call that a zero but if you receive a frequency it looks like this when you call it so if i want to send some of the message one zero one one all of you so send them this signal i'd change the frequency so alexander one first here's one allison zero that's another one