Some FAQ's

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Some FAQ's

Post  Cobra on Tue Jan 29, 2008 5:41 am

www.advancedspecialties.net wrote:
WHAT IS SIDEBAND (SSB)?
A - "Sideband" (SSB) is a mode capability found in higher-end CB Radios. You will have access to the Upper & Lower Sideband Modes (USB, LSB), In addition to the "Regular" (AM) mode on each of the 40 channels. When switched to sideband, each receive signal must be "fine tuned" in with the clarifier or voice lock control found on the SSB CB radio, otherwise people will sound garbled or distorted. Keep in mind that when switched to a sideband, you can only communicate with other CBers that have that capability. You can usually expect an increase in range, & less noise than on the "standard" AM 40 channels.

WHAT IS THE "TALKBACK" FEATURE?
A - If your CB has Talk-Back, this is a feature that lets you hear or "Monitor" yourself thru the CB Radio's speaker while you are transmitting. It can be useful to check the sound of power & Echo type mikes. If turned up too high, you will get a feedback squeal, however.

WHAT RANGE WILL A CB RADIO GIVE ME?
A - "Generally Speaking" range for a mobile CB Radio could be anywhere from 1 to 20 Miles or more, depending on terrain, type of antennas used & other factors. The "typical" range to expect from a mobile CB, with a good antenna, is about 2 to 5 miles, & you will actually get more or less than these numbers in certain areas & terrain, & as you drive. Home Base Station CB setups, with larger roof mounted Base antennas, will usually give more range than the ground level mobile units do.

WHAT DO THE RF & MIKE GAIN CONTROLS DO?
A - Mike Gain (or Dyna-Mike), is your microphone's transmit "volume control", & can be lowered to reduce background noise, or if your voice is really loud. The RF Gain control can be thought of as a "Receive Distance Control", & by turning it down you can reduce the radio's sensitivity to distant chatter, noise & signals that are too weak to reach. The Better CB's will usually have both of these controls.

WHY DOES THERE SEEM TO BE MORE STATIC ON CB CHANNELS THAN WHAT I HEAR ON OTHER TYPES OF RADIOS?
A - Just like you car Stereo's AM/FM Bands, where the "AM" has more interference than the "FM", CB channels are transmitted & received using a similar "AM" type of transmission mode. Other two-way Radios like FRS, GMRS, Police scanners etc. all receive in an "FM" mode. Again, with CB, just as switching to "AM" on your car stereo, you will notice more static than when on FM. Look for CB Radios that include a Noise Blanker ("NB") switch, which helps minimize some of the noise better than standard CB's that have no noise filters, or just an "ANL" switch.

IS THERE A CB MADE WITH A BUILT-IN POLICE RADIO SCANNER?
A - No. Some Scanners, such as the Uniden BCD-996T, BC-246T or Alinco DJ-X2000T & DJ-X7T will receive the 40 CB channels, but none will transmit.

WHAT IS THE BEST ANTENNA FOR MY MOBILE CB RADIO?
A - This is tough to answer, & there are many variables, but here are some good general guidelines & "Rules of thumb". First, The Taller the antenna, the better it will work. Mount your antenna as high as possible on the vehicle, & try to get at least 50% of it over the roofline. Usually, all else being equal, the tallest, or longest antenna you are comfortable with, mounted as high as possible, will give the best performance. For Example, mounting a new 4 ft CB antenna where you were using a 2 footer, will usually give better results. It wouldn't matter what "brand name", color or style the 2 ft antenna was. Keep in mind that CB antennas that are less than 3 feet tall, those that "stick to the glass", & the AM/FM/CB "combo" antennas & adaptors generally do not give the best performance, they are mostly bought & sold mainly for "convenience" & "cosmetic" reasons.

WHY DO I SEEM TO LOSE A PERSON'S SIGNAL QUICKLY WHEN MOBILE?
A - This is a common question. Remember, in some types of terrain and/or driving speeds, you can lose another Cabers signal rather quickly. For example, two mobiles traveling about 60MPH, going in opposite directions become a mile apart every thirty seconds! There are many situations where that would be enough to lose each other within a minute or so, depending upon terrain, antennas etc..

ARE CB TRANSMIT AMPLIFIERS (BOOSTERS, MODULATORS, LINEARS) OK TO USE, & CAN I BUY ONE?
A - It is against FCC rules to use an external transmit Amplifier on CB radio channels in the USA. It is also against current FCC rules to sell or market amps that are capable of operating "out of the box" between 24-35 Mhz frequencies (CB falls within this range). That being said, there seems to be many places that sell them anyway.

DO I NEED A LICENSE TO OPERATE A CB?
A - No, since the early 1980's, the FCC stopped requiring licenses for USA CB radio use. Users must still abide by the FCC rules regarding the CB Band, however.

IS THERE ANY LICENSE I CAN GET OR BUY THAT WILL ALLOW EXTRA CB CHANNELS OR HIGHER POWER? &
HOW MANY CHANNELS CAN I HAVE IN MY CB RADIO AFTER I GET A HAM LICENSE?
A - ALL USA CB radios are allowed only the 40 26-27 Mhz CB channels, they must be FCC approved for CB use, & have 4w AM/12W pep SSB maximum output power, license free. There is No "Ham", Business or Commercial License that will allow the user to run higher Power, use "extra" channels, buy/sell CB amps or modified Amateur Rigs in the 11M 26/27Mhz CB Radio Band.

WHAT IS THE "FREEBAND" or "OUTBAND"?
A - These Terms refer to frequencies or "Extra" channels that are directly above or below the standard 40 CB channels (approx 26-28Mhz). While not FCC assigned for CB or Amateur use in the USA, These 11 meter frequencies are never the less very popular (worldwide), & mostly used by "bootleg" CB & Amateur operators that internally modify their CB, Amateur, "Export or 10 Meter Radios to "reach" these channels. Although many of these frequencies are still technically assigned for commercial or other users, Most legitimate licensed users of these frequencies abandoned them long ago, & now you will usually only hear "unlicensed operators" when monitoring these frequencies.

IF I WANT TO USE A MOBILE CB AS A HOME BASE STATION, WHAT WILL I NEED?
A - Besides a good Base Station CB Antenna, you will need a Regulated Power Supply, to convert the "120vac House current" to 13.8VDC "Car current". Most Standard CB radios Draw Less than 4 Amps, so a good Regulated unit, rated between 4 and 6 amps output will suffice. See our Online Catalog for Power Supply Selections, such as the Pyramid models PS-7KX & PS-8KX.

IF ALL CB's ARE LIMITED TO 4W & 40ch, ISN'T A $59 SET AS GOOD AS A $200 RIG?
A - NO. It's like saying, "Since all AM/FM car stereos pick up the same stations, isn't a $50 unit as good as one that sells for $500". Factors like receive sensitivity & selectivity, Noise Filtering & modulation quality will all be better in a more expensive model. You get what you pay for. Also, features like Mic & RF gain controls, built in meters, noise blankers & more will also vary with different CB's.

WHAT'S A POWER MIKE?
A - "Power-Mikes" are replacement microphones for a CB radio that require a battery, and are amplified. They do not give the radio more power (watts), but most good ones usually sound much better, clearer & louder over the air than the cheaper plastic "stock mics" that are packaged & sold with the CB. They also allow the user more versatility, to speak a little farther from the mike than with the "stock" unit, & help amplify softer voiced people too. Some Power mikes include "Hobby" type controls such as "Echo/Reverb", or sound effects, while others do not.

WHAT IS A "NOISE CANCELLING" MIKE, & WHAT DOES IT DO?
A - This is a microphone designed to reject more background noise, & only pick up the user's voice close to the mike, as compared with a standard mike. It is useful to truckers & drivers that have Loud engine or road noises as they drive, but is not really necessary in a quiet car or a base station setup.

WHAT IS "SWR" & ANTENNA TUNING?
A - SWR (Standing Wave Ratio) is a measure of how well your antenna is "matched" or "tuned" to operate at CB frequencies, & to your vehicle. Unlike TV or Scanner antennas that do not transmit, the CB & other "transmit" antennas need to be tuned to operate or Transmit correctly & efficiently. If severely "out of tune" (or having a poor SWR reading), damage to the transmitter can result. While most good CB antennas, when mounted & grounded correctly as the maker intended, will usually have a "safe SWR", keep in mind that it is still a good idea to check & optimize your SWR reading. Regardless of Mfgr's claims, there really is no way to "Factory pre-tune" mobile antennas for CB frequencies. The same exact antenna can actually give different SWR Readings when mounted on different vehicles, or even in different spots on the same vehicle! Remember, When Setting the SWR you are NOT Matching the Antenna to the Radio, but rather the Antenna to the vehicle.

HOW DO I CHECK MY ANTENNA'S SWR TUNING?
A - It's fairly easy, you will need either an SWR meter function built into your CB radio (e.g.. a Cobra 29, Texas Ranger TR-966 or Galaxy DX-959 / DX-979), or an external SWR meter hooked between your radio & antenna (e.g.. Pyramid SWR-14). Follow the directions that come with the meter. Readings above 3:1 ( "Three to One" )are considered bad or even dangerous, readings of 1.5:1 ("One point five to One") or lower are considered excellent. Readings around 2:1 are safe, but an effort should be made to tune the antenna for a lower reading. Actual tuning of the antenna will vary by type, but usually involves raising, lowering or trimming a whip or tip element, or adjusting a ring or tuning control at the top or bottom. Some antennas are factory sealed & not easily tunable, We would not normally recommend these for a performance setup. Remember, the Meter or radio can only check the SWR, not change it. Tuning the SWR reading must be done at the antenna itself. Most local CB installation shops will charge about $10 to test & tune your antenna, if you'd rather not attempt it yourself.

WHAT ARE THE CURRENT BRANDS OF CB SETS AVAILABLE?
A - The major currently sold brands in the USA & Canada are Cobra, Ranger (Texas Ranger & Virage), Galaxy, Uniden and Midland. Check our OnLine CB Radio Catalog for our current offerings.

IS THERE A WEB PAGE TO COMPARE FEATURES OF DIFFERENT CB RADIOS?
A - Yes, We've Taken care of that!! See our CB Radio Feature Comparisons Page To see charts of AM & AM/SSB feature comparisons!.

WHAT IS A "ROGER BEEP" & WHAT"s IT FOR?
A - The Roger Beep is a single or multi tone that is transmitted for a brief second when you un-key your mike. This was originally intended to give a true confirmation to the receiving station of when the other person was finished talking, especially during weak signal & SSB reception. Most modern day CBers simply use it for "fun & games" however & it should be turned off if others find it annoying. Some CB sets have this feature built in (Galaxy DX-2547 & DX-959, Texas Ranger TR-396F), or it can be purchased in an optional power mike or internal add-on board.

WHAT IS A "GROUNDPLANE" & WHAT ABOUT ANTENNAS FOR FIBERGLASS OR NON METALLIC SITUATIONS?
A - Most mobile antennas are actually "half" of the antenna, the other half is the body of the car or truck. This "other half" is also known as the Ground Plane of the antenna. If the Ground plane isn't adequate or large enough, poor SWR readings & performance will result. There are special "No Ground Needed" antennas designed for Boats, Fiberglass Door Trucks etc. Some of these antennas require a special included cable that can't be cut or replaced, others can be used with any cable. If a regular CB Antenna is mounted fairly close to the vehicles ground, such as on a truck's fiberglass door, sometimes running a thick ground wire from one of the mounting bracket's bolts, to a good chassis ground, can sometimes work & allow the use of "standard" mobile CB antennas.

WHAT SHOULD ONE "WATCH OUT FOR" WHEN ORDERING / BUYING CB RADIO EQUIPMENT?
A - There are some things to avoid, that may be unknown to a person "new" to CB.

--* First, remember that in most cases it's mainly the physical size of the antenna that matters, & don't get suckered into buying a smaller antenna by advertising gimmicks. There really is no way to design a 3ft CB antenna to work consistently better than a 5 footer, regardless of the brand name, "dB gain", "loading" or "wavelength" claims of the Mfgr.

--* A few CB's seem to claim 5, or even "7 watts of power" on the box. This is misleading, it actually refers to the Audio power sent to it's built in speaker, "input" power, or some other nonsense that has nothing to do with the actual transmit output to the antenna, which is still 4w or less in that radio. In fact, it is usually the small, thin "cheaper" bottom-end CB radios & "Walkie Talkies" that make these claims!
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