Saturday, September 14, 2013

Basic Equipment for CB Radio

Basic equipment for CB Radio is combine of  a Radio (or Rig) it shelf, Power Supply Unit (PSU), Antenna and coaxial or twin lead cable.



Basic CB Radio:
Have one Band and 40 channel's, of AM (amplitude modulation) and FM (frequent modulation) modulation, and have a 1W (Wat) of output power on AM modulation and 4W on FM modulation. But this variate form country to country and theirs law (eg. in some countries you can legally only have 40 FM channels and and 12 AM from 4th to15th channel). And run on 12-13,8 volts and the amount of current hay need witch depends on the radio ti shelf, its output power, modifications and more...

Basic CB Radio
Power Supply Unit:
Depends of your CB transceiver current consumption, for basic AM FM transceiversh with maximum 4W output power you while need a 12-13,8 volts, 4A (amps) DC regulated power supply or bather. But most Radios CB ore HAM runs on 12-13,8 volts and need all kind of current from 1A or 2A all the way to 5A, 10A or 20A depends (of output power, modifications, accessories and rig it shelf). So basically you can put one in your car and run it on the 12V battery or take it in the house and run it trough a 12-13,8V PSU.
The power supply on the picture below have 13.5v of 10A, but do not get distracted if your radio need 4A he while take only 4A from PSU, not all 10A so the radio while not get fried. And the lack of 0,3v while not make differences because the radios are working in the range of 12V to 13,8V as I say before.
Just be sure to match the colors of the Radio power cables with the  color of the PSU output knobs bee sure that + (red) or -(black) are not mixed because that can fry the radio.




The Antenna:
First the frequency of CB Radio is 27Mhz or 11m wave length. There is all kind of size, shapes and types of antennas. Size variate from 1/4 to 5/8 and full wave length of 11m. Types are mobile(on cars and trucks), vertical, horizontal (or dipole), and yagi (pointed vertical or horizontal or bout).


Mobile Antennas
Are use on Truck, Automobile, Motorcycles, Bicycles and pretty much on everything that moves. As you can see they comes in every shapes and sizes.

Vertical Antennas
Vertical antenna also comes in all shapes and sizes, but the most popular are 5/8 GP (Ground Plane or antenna with radials) or single rod. 5/8 means that you have antenna that is 5/8 of a wave length (11m or 36.0892 foot). On the image below you can see Vertical Rod and GP or Ground Plane antennas, the closer one is a GP Antenna and their are bout 5/8 of wave length. GP antenna can have 3 or 4 radials.
The good old dipole can be a simple wire or aluminum tube and of course it can be vertical ore horizontal mounted. And it is the simplest antenna for homemade production fore the beginners, but it can also and not to often use by lets call them pro CB'ers. 

Horizontal Dipole
Vertical Dipole
The Yagi Beam Antennas work and have same principles as the others antennas bud do to the element allows you to point your antenna at the specified part of the lets say world.

3 element horizontal yagi

Left  element vertical and Right 6 element horizontal and vertical yagi
                     

Sunday, August 18, 2013

Let us get started


But First The History of CB radio.....

It is a form of shot-distance communication between individuals on the 27-Mhz or 11meter band frequency, on selection of 40 channels. But the channels and the law of using a CB radio variate from country to country. In many country's CB operation dose not require a license, unlike Amateur Radio where you have to pass the test to be able to operate . It may be use fore business or personal communications, like many other two-way radio services. CB channels are shared with many other users and it can be fun to talk or just listen to them.

Old Vacuum Tube CB Radio

 CB radio or CB Radio service originated in the United States as one of several personal radio services regulated by the Federal Communications Commission (FCC). These services began in 1945 to permit citizens a radio band for personal communication fore family and business communications and radio-controlled model airplanes (actually some of today's toys steal use a 27-Mhz transmitters an receivers to control RC vehicles). 
Old Vacuum Tube CB Radio
                                  
In 1948, the original CB Radios were designed for operation on the 460–470 Megacycle UHF band. There were two classes of CB radio: A and B. Class B radios had simpler technical requirements, and were limited to a smaller frequency range. Al Gross established the Citizens' Radio Corporation during the late 1940s to manufacture Class B handhelds for the general public.


On September 11, 1958 the Class D CB service was created on 27 MHz, and this band became what is popularly known today as CB. Back in the day's there were only 23 channels at the time; the first 22 were taken from the former Amateur Radio Service 11-meter band, and channel 23 was shared with radio-controlled devices.Some hobbyists continue to use the designation "11 meters" to refer to the Citizens' Band and adjoining frequencies. Part 95 of the Code of Federal Regulations regulates the Class D CB service, on the 27 MHz band, since the 1970s and continuing today...

1970s CB Radio


During the 1960s, the service was popular among small businesses truck drivers and radio hobbyists. By the late 1960s advances in solid-state electronics allowed the weight, size, and cost of the radios to fall, giving the public access to a communications medium previously only available to specialists.CB clubs were formed; a CB slang, language evolved alongside 10-codes, similar to those used in emergency services.



CB has lost much of its original appeal due to development of mobile phones, the internet and the Family Radio Service. Changing radio propagation for long-distance communications due to the 11-year sunspot cycle is a factor at these frequencies. In addition, CB may have become a victim of its own popularity; with millions of users on a finite number of frequencies during the mid-to-late 1970s and early 1980s, channels often were noisy and communication difficult. This caused a waning of interest among hobbyists.The advantages of fewer users sharing a frequency, greater authorized output power, clarity of FM transmission, lack of interference by distant stations due to "skip" propagation, and consistent communications made the VHF (Very High Frequency) radio an attractive alternative to the overcrowded CB channels.
Channel 9 is restricted by the FCC to only emergency communications and roadside assistance. Most highway travelers monitor channel 19. CB radio is still used by truck drivers, and remains an effective means of obtaining information about road construction, accidents and police radar traps.




All frequencies in the HF spectrum (3–30 MHz) can be refracted by charged ions in the ionosphere. Refracting signals off the ionosphere is called sky-wave propagation, and the operator is said to be "shooting skip". CB operators have communicated across thousands of miles and sometimes around the world. Even low-power 27 MHz signals can sometimes propagate over long distances.
The ability of the ionosphere to bounce signals back to earth is caused by solar radiation, and the amount of ionization possible is related to the 11-year sunspot cycle. In times of high sunspot activity, the band can remain open to much of the world for long periods of time. During low sunspot activity it may be impossible to use skywave at all, except during periods of sporadic electron propagation (from late spring through mid-summer). Skip contributes to noise on CB frequencies. In the United States, it is illegal to engage in (or attempt to engage in) CB communications with any station more than 250 km (160 mi) from an operator's location. This restriction exists to keep CB as a local (line-of-sight) radio service; however, in the United States the restriction is widely ignored. The legality of shooting skip is not an issue in most other countries.



Hi to all

My name is Branko.
And I am a CB'er or CB (Citizen's Band) radio operator. And I open this Blog to share or maybe even teach some one something about being a CB'er or Ham-radio operator.....