Originally posted by mark g8awo
CB has a range of about 5 miles mobile to mobile but that depends on the lie of the land and where abouts you site the aerial on the car and on a truck if you have a metal body to the rear which alters your polar diagram.
Now if you use a base system you can increase the range by the use of a more efficient aerial which the rules have been relaxed since the original concept of a 1.5m radiating element. You are allowed to use a 5/8 wave aerial which is about 21ft this gives a theoretical gain over a quater wave aerial if 6db which when put into maths terms is 4 times the efficiency. This is a theoretical gain and not true gain as you can only really gain an increase of signal by using a beam which focuses the signal into one direction. As a CBer you are not allowed beam aerials at all.
Height can also be a factor to improve the range for the obvious reasons but we also have another thing that also comes into play and that is what we call a lift, this is atmospheric and temperature dependant you can get anything from 40 miles to a few hundred miles by this method.
Now here is the best one the Sun also plays a contributary factor if you look at www.Spaceweather.com you can see a up to date image of the sun spots. As the number of sun spots increase over the next few years the range can increase to a few thousand miles and the US is not going to be uncommon.
Another one that gives a lot of people some fun is a solar flare which generates a Aurrora otherwise known as the Northern Lights. By using a beam on the VHF bands on these conditions and aiming north, now VHF is known as a line of sight comms you may get 10 miles under normal conditions but using the aurrora we can happily work into Russia, Scandinavia, Germany and further but every body is doing the same and lookin north. The down side to the Aurrora is the fact for anything from a few hours to a couple of days or so the HF bands are dead and you are lucky to talk to the other end of the country as the magnetic fields of the Earth are still disturbed......
I hope this helps your thoughts if i have some of the facts wrong i appologise cos I`m only human and im working from memory...and im sure there are some more knowledgeable people than me.
Now if you use a base system you can increase the range by the use of a more efficient aerial which the rules have been relaxed since the original concept of a 1.5m radiating element. You are allowed to use a 5/8 wave aerial which is about 21ft this gives a theoretical gain over a quater wave aerial if 6db which when put into maths terms is 4 times the efficiency. This is a theoretical gain and not true gain as you can only really gain an increase of signal by using a beam which focuses the signal into one direction. As a CBer you are not allowed beam aerials at all.
Height can also be a factor to improve the range for the obvious reasons but we also have another thing that also comes into play and that is what we call a lift, this is atmospheric and temperature dependant you can get anything from 40 miles to a few hundred miles by this method.
Now here is the best one the Sun also plays a contributary factor if you look at www.Spaceweather.com you can see a up to date image of the sun spots. As the number of sun spots increase over the next few years the range can increase to a few thousand miles and the US is not going to be uncommon.
Another one that gives a lot of people some fun is a solar flare which generates a Aurrora otherwise known as the Northern Lights. By using a beam on the VHF bands on these conditions and aiming north, now VHF is known as a line of sight comms you may get 10 miles under normal conditions but using the aurrora we can happily work into Russia, Scandinavia, Germany and further but every body is doing the same and lookin north. The down side to the Aurrora is the fact for anything from a few hours to a couple of days or so the HF bands are dead and you are lucky to talk to the other end of the country as the magnetic fields of the Earth are still disturbed......
I hope this helps your thoughts if i have some of the facts wrong i appologise cos I`m only human and im working from memory...and im sure there are some more knowledgeable people than me.
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