# School project how deos a cb work im doing a school project on radio waves

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When you talk into the microphone your voice which is sound pressure is converted to electrical voltages then it is increased in power to about half of the power of what the CB will sen out to the antenna. To make the CB radio transmit, there is a circuit that creates the proper frequency or channel. It is then increased to about twice the power of the voice circuit. They are combined together just before it goes into the antenna.It leaves the radio and goes into the antenna where it leaves the antenna as an electromagnetic wave. Electricity in the air with a certain value of frequency and strength. When the CB receives, The antenna picks up a signal, an electromagnetic wave, as it passes by. The electromagnetic wave, which is a small voltage, with a certain frequency and strength, enters the radio where it is processed . It is then increased in power . It is now connected to a speaker. The speaker is also a converter. It converts electrical voltage back to sound pressure so we can hear it. As the electrical voltages make the cone of the speaker move in and out. There is a lot more detail than this but this should help. Many things happen inside the radio that cant be explained in a few paragraphs.

Posted on Dec 13, 2011

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• Iron Dec 13, 2011

No mention of crystals, filters. IC chips or anything. Typical espert.

• Ernest Taylor Dec 14, 2011

Now when the new 40 channel radios came out they eliminated most all the crystals.
They really only needed one crystal for the transmit stage to do all 40 channels. Yeah right you say? The circuit uses a phase lock loop to come up with the right frequency. How it works Is somewhat like this: the crystal is attached to an integrated chip that has a job of dividing the frequency by a certain number. Like say divide by 11,456. Just an example. The end result would be a frequency which was fed back to the input and then it would lock itself on frequency. Its a lot more than that and complicated. Now to get more channels other than 40 channels all you had to do is figure out the combination. You the 40 channel selector knob on your radio is actually selecting different combinations of the chip input leads. By changing those combinations you could go above channel 40 to 41,42,,,,,60 or more. Which of course is illegal. other than that the new ones are equipped with noise blankers to get rid of power line noise and other noises. I think that is enough detail as I am not writing a book. If any of you care to elaborate feel free. Please no more sarcasm. I am only trying to help. not everyone is at the same learning level. It takes time to answer questions in such detail, time I could spend doing other things. I don't mind helping but I am limited to how much time I can spend. By the way you spelled expert wrong, you spelled it "espert".

• Laron Aug 24, 2012

ALL HAIL THE MIGHTY IRONFIST109!!!!!!!!!!!!!! I am a fan not to be confused with stalker. His material makes for a informative and accurate on subject read. Can't help but rate his comments as helpful.

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It is a simple transmission between magnetic wave forms exchanged by two consistent receivers using the sam frequency and modulation. For example, when you key in on a CB microphone, the CB is sending electronic pulses to the mic and when you talk, the waves are sent to the CB and transformed into radio waves by the transmitter and are sent to other components of the CB like if you had an echo board on the CB, if you had the echo activated, the wave would pass through the echo board and would be transformed dramatically depending on how you set the echo, then after the transformation of the waves, they would be sent through your antenna, through the air and then into other people's CB receivers.

Hope this helps!

Posted on Jul 01, 2008

Hi,
a 6ya Technician can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repair professionals here in the US.
Goodluck!

Posted on Jan 02, 2017

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