All signals reduce at the square of the distance - this is called the Inverse Square Law.
Inverse-square law - Wikipedia, the free encyclopedia
Signals above 3 MHZ to 30 MHZ benefits from a propagation called Sky Wave -
Skywave - Wikipedia, the free encyclopedia
Radio waves between 30 KHZ and 300 KHZ are affected by a propagation called Ground Waves -
Surface wave - Wikipedia, the free encyclopedia
What we are talking about here is CB - 27 MHZ - where a person in a mobile wishes to talk to another person in another mobile or a base 1 - 20 miles away.
This is called Line of sight propagation -
Line-of-sight propagation - Wikipedia, the free encyclopedia
When you put a building or a hill or a mountain or a forest of trees between the transmit TX and receive antenna's - RX - this is called Non Line of Sight -
Non-line-of-sight propagation - Wikipedia, the free encyclopedia
There is a fellow in Monterey Mexico that was known for television DX back in the days of analog television - 1000+ miles away.
This is not to say that he can still do it today with Digital television - due to the fact that most network stations has migrated up into the UHF where it takes 10 times the amount of TX to reach the same market as analog VHF.
What I am trying to explain to you people is how to make your CB radio work and work better then if you just take a cheap CB radio and put some power to it and put a mag mount antenna on the roof 1/4 wave or install a antenna to the side of the vehicle someplace and hope that it will work.
This is called BROADCASTING.
It doesn't matter if you use a 1 KW transmitter - television translator which might transmit 20 - 40 miles depending on propagation or a 1000 KW transmitter that might only transmit a receivable signal 65 miles away like most UHF television stations not near a large body of water - such as in Pennsylvania. Increases in power only produces nominal gains in range.
Broadcasting depends on certain things to happen to work.
You need an antenna of a certain size at a certain height - which for a CB antenna to work - you need at least a 1/2 wave antenna - also known as a dipole or a 5/8 wave antenna - such as the old 117 Super Magnum Antenna Specialist.
You also need some sort of ground plane - which the 117 made its own with it's droopy ground plane design and you also needed a established ground - 3 stakes pounded into the ground and one of the ground stakes bonded to the electric company ground below the meter base.
It also needed to be at a certain height - at least 33' above ground level.
Unless your automobile was a blimp - there isn't no way to get it 33' above ground level.
You needed a coax sufficient enough to carry the signal from the radio to the antenna and with as little loss as possible - so you could listen to what you were trying to talk at.
4 watts - if it had something to bounce off of - would talk half way around the world.
BUT - you had to have a certain type of propagation in order to do it and that type of propagation does not happen every day.
Mostly in the late spring / early summer and a couple of days in the winter - if you could get some kind of inversion layer in the upper atmosphere.
The ground plane is the vehicle, as long as the antenna is on the highest point on the vehicle and is properly grounded and matched and the transmitter is aligned - it might talk 1 mile or it might talk 10 miles. I can't tell you that - because I do not have a crystal ball.
Now take any one of the variables out of the equation and all of a sudden you end up with a radio that doesn't work the way the person that owns the radio wants it to work.
Nobody spends $100+ dollars on a radio and antenna and then is satisfied if it doesn't work.
That's the reason why a person should buy their cb radios from a cb radio shop and that is the reason why a person should pay a professional installer to install the radio for them.
Maybe some people gets my advice confused with fighting, I don't know.
The fact is - that the right person can take a box stock radio and make it sound better then a radio that a person spend several hundred dollars on and then had it tweaked and tuned and then bought some type of ridiculous antenna to try to make it work.
I could put a Ringo Ranger antenna on my truck - but it wouldn't work right for very long or last very long - or be very legal since there is probably height and size restrictions in place from the dot.
I'm just trying to help the guy out here.
TV and FM DX - Wikipedia, the free encyclopedia
