questions about cb amplifiers...
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Theyre illegal because the fcc has limitations on how much power you can be transmitting with without a licencse. And then if you did have a licencse the CB band is probably the thing thats limited, they dont want people pumping too much juice out in those bands and hogging it all maybe?
So what they do is just (im pretty sure) take the signal to be broadcasted at the normal 4 watts the cb putts out and ups it a number a watts so that it will go farther and be clearer closer by too. On the recieve half of the amp im not too sure what it does... maybe amplifies that too and lets the cb pick out wahts noise and whats not.
Thats all I know... call one of your local "small time" cb shops and see if you can get anything out of them to see who sells them and whatnot.
So what they do is just (im pretty sure) take the signal to be broadcasted at the normal 4 watts the cb putts out and ups it a number a watts so that it will go farther and be clearer closer by too. On the recieve half of the amp im not too sure what it does... maybe amplifies that too and lets the cb pick out wahts noise and whats not.
Thats all I know... call one of your local "small time" cb shops and see if you can get anything out of them to see who sells them and whatnot.
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thats pretty close, here is another viewpoint. cb amps are kinda like NOS or police scanners, legal to have but not to use. here is a problem with that though, a lot a cb'ers use them to get up and over the noise, so others get larger amps to get over the first group, and so on and so on, next thing you know, the guy down the street has a set up for 1000 watts or something. What is usually good enough and while technically still a no no, is more ok than an amp, is to have the radio "tuned" by a proffesional cb'er. take a nice radio like the cobra 25 or 29, out of the box puts out 4 watts, with a turn of the right screw, can put out 20 watts, which is usually enough to get out. figure an average range of 1watt = 1 mile. alos on the receive side of the amp, it just amplifies everything, noise and words, so you can hear people further off.
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Where did you find out where to "turn the right screw" to pump that cb? I am looking for a cb and like to know what one to modify? thanksd0wnf0rcec0ncepts said:
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I'm pretty sure that if caught with a linear amplifier you will be in deep doo doo. Everything i have ever heard and read said that, if it's in your possession like in your car or in your home no matter if it's hooked up or not your busted. So it's more like drugs, not like NOS or a scanner.d0wnf0rcec0ncepts said:
Now being a Satelliet/Wideband and Telementry Systems Technician I think i can jump on this thread and offer a little bit of knowledge. CB radio's used to actually required a licence when they first came out, after some time the FCC dropped the licence requirement for CB because of it's popularity and now it's free for all. Plain and simple CB's run in very low frequencies these frequencies are part of the Citizens Band, a part of the electromagnetic spectrum that is set aside for people like you and me to use absolutly free of charge. The reason for the limit on power amplification is because they give us 40 channels to us and IT"S FREE...they don't want you to use too much power and be transmitting for hundreds of miles. It is actually illegal to transmit over 155.3 miles on CB. When talking about frequencies as low as the frequencies we use in CB 26.965-27.405 they are capable of traveling long distances if given enough power or the atmospheric conditions are right. Now say you are having a conversation on channel 19 and 15 miles up the road someone else is having a conversation on that same channel, well with your regular 4 watts you should have no chance of bleeding into his conversation, that's the way the FCC meant it to be. So we can all SHARE. If say Joe Blow hase a 200 watt linear amplifier hooked up and decides to key up his radio to yell at the trucker who just cut him off then he will most likely interfear with everyone's conversation within that 15 mile radius....(this is just an example not exact distances or wattages) Point being the limit on power is there to make everyone happy and to stop as much interfearance as possible so everyone can use CB and be happy...now another thing is if one channel is busy switch to another channel that's y they are there. Now everyone knows that people can't leave good enough alone and to tell you the truth CB isn't good enough for our purposes, when out great distances from civilization you need to transmit greater distances sometimes...then theres the other power hungry people that just want to transmit over other people like mentioned in the above post. Yes putting out more power will jam the others and only your voice will be heard on that channel because you are higher above the noise floor than the guy abiding by the law putting out only 4 watts. Well in my openion if you need to transmit farther distances go get a radio operator licence and run a radio of higher frequency, then you can run your high power and transmit farther and it's all leagal so you won't have to worry about being smacked with a fine or thrown in the slammer for doing something you can do legaly if you had the licence.
Oh yea and about the receive side well yes you can amplify the receive side and then use your squelch to block out all the noise below a certain point on the noise floor. Everything is amplified but the squelch will only let the higher power signals through that are higher above the noise floor than the point set by the squelch knob.
And how does it all work? Well the amplifier takes the modulated signal at the previously amplified 4 watts and amplifies it more then sends it out through the antenna, but someone already stated this.
If you want to konw more about it do a search for linear amp in google and there's TONS of info on the web and they can explain everythign exactly. There's schematics and directions to build your own linear and most probably places you can buy them...weather or not you need a licence to do so i can't tell you...i never messed with it all too much. I'm pretty sure it's illegal to sell to someone without a licence both the linear amp and the instructions to build them but i'm sure they are available. It's all out there you just have to look for it and read read read.
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This is straight from my CB Radio FCC Rules book. FCC Part 95 Subpart D CB Rule 11c
The FCC will persume you have used a linear or other external RF amplifer if -
1. it is in your possession or on your premises;
AND
2.There is other evidence that you have operated your CB station with more power than allowed by CB rule 10.
CB Rule 11d Paragraph c of this rule does not apply if you hold a license in another radio service which allows you to operate an external RF amplifier.
You should have gotten a CB Radio FCC Rules book when you bought your cb radio, i did but i don't konw if every radio brand puts the book with it...if you did though and you have any questions on what's legal and what's not this book will answer your questions, if you don't have one do a google search for CB FCC laws or rules or something to that nature, i did one and got pretty much the same info that was in the book.
Hope this clears things up.
The FCC will persume you have used a linear or other external RF amplifer if -
1. it is in your possession or on your premises;
AND
2.There is other evidence that you have operated your CB station with more power than allowed by CB rule 10.
CB Rule 11d Paragraph c of this rule does not apply if you hold a license in another radio service which allows you to operate an external RF amplifier.
You should have gotten a CB Radio FCC Rules book when you bought your cb radio, i did but i don't konw if every radio brand puts the book with it...if you did though and you have any questions on what's legal and what's not this book will answer your questions, if you don't have one do a google search for CB FCC laws or rules or something to that nature, i did one and got pretty much the same info that was in the book.
Hope this clears things up.
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There are no licensing requirement for CB, amps are illegal period. But if you use one smartly you can get away with it as amps are quite common with truckers and hobbyists. Id like to have one buts its not on my priority list. heres a good forum for cb's...bigd9247 said:
http://www.cbradioforum.com/
ok thanks everyone for the information. now then i don't want anyone to think that i am someone that wants a 200watt cb or anything like that so i can stomp out everyone else. because that is not the case. i was just curious as to why they are illegal. but i would like a SMALL amp so that i can transmit better. what do you guys think about something like 10, 15, or 20 watts? i wouldnt get caught with anything that small would i? and it wouldnt interfere too badly with other conversations would it?
also, i would like to know how it is possible to tune a cb to put out more power? i dont see how that can be done because the cb should have a very small internal amp which should only be big enough to supply close to 4 watts because that is the legal cut off and it would be wasted money for the cb manufacturer to put a stronger internal amp inside the cb because it would never get used. (sorry for the huge run on sentence) but if i am wrong and that is possible, i would really love to know.
also, i would like to know how it is possible to tune a cb to put out more power? i dont see how that can be done because the cb should have a very small internal amp which should only be big enough to supply close to 4 watts because that is the legal cut off and it would be wasted money for the cb manufacturer to put a stronger internal amp inside the cb because it would never get used. (sorry for the huge run on sentence) but if i am wrong and that is possible, i would really love to know.
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bud, try the link i posted above. no you wont get caught esp w/ a small amp. the FCC is plain lax on their enforcement of CB radio regulation. yes (maybe) the factory amp can be tuned, but i know for sure "peak and tune" is a common mod for a new CB. Try a 60 watt amp that should be plenty. But definitely visit the site i posted cbradios.net (retailer) and cbradioforum.com (same retailers forum)bigd9247 said:
I have been CBing for at least 10 years and now I have my amatuer radio liscense. Most of those years I was running way more than 4 watts. Almost any CB radio that you buy is capable of 12 or 15 watts without using an amp if you have it properly tuned. Many radios are very simple to tune and would be no problem for an individual with little technical knowledge as long as you have some kind of meter to measure the output and adjust accordingly. Tuning information is available all over the internet for most common radios. Snakedoctor at http://www.angelfire.com/ks/cbmods/ offers mods for many common CB radios. Your basic chrome faced Cobras like the 25 and the 29 will tune up nicely and sound great with a better microphone (most stock mics suck). 25s and 29s can do around 20 watts with a little tuning, just dont clip the modulation. Many tuning instructions say do this but you will sound loud and crappy instead of not quite as loud and really good. Cobras are not the only good radios out there. Midland makes good radios that are capable of more than 4 watts output. Many Midlands are also capable of more channels. There are 40 legal CB channels not counting single side band (but that is a whole nother topic). However, many Midland radios are capable of 120 channels and some are capable of 240 channels. What good is more channels? Well the top 40 as I call them can get really busy and having say 120 channels gives you more options for finding a clear channel. Uniden makes many fine radios some of which are internally identical to the aformetioned Cobras. In our trucks space is an issue and I went with the Midland 79-290 which is small but not as small as some. If I were going to go very small and digital as opposed to a more conventional style like the Cobra 25 or 29, I would choose a small Midland rather than a small cobra because of the possibilty of more channels.
On the subject of amps. They are certainly illegal and the much esteemed former president of the US, Bill Clinton, signed a law that allowed local PDs to enforce the laws of the FCC concerning illegal CB radio equipment. That being said most Cops wouldnt know what they were looking at anyway. You may get caught if you key up an amp when a Cop (no slam intended) is very near you because you may blow over his radio and he will know somethings up. Typically, amps start out around 100 watts. Having the option of flipping a switch to bump up your power to 100 watts is very nice. 100 is plenty for most anyone. The only limit to how much power you can run is how much your battery and alternator can support. I run a 250 watt amp. I rarely ever use it. The only time I do is when I am talking with someone and the terrain or range begins to cause a problem. Then I usually turn it on to finish the conversation because once the signal starts to fade it goes very quickly. The mile per watt number is not accurate. 200 watts is not going to get you 200 miles. To put this simply if 4 watts goes 4 miles then you will need 16 watts to talk 8 miles then you will need 256 watts to talk 16 miles. You get the idea. Of course all of this depends on terrain and other conditions. These numbers are not exact but the idea is that you have to pretty much square the power output to double the distance. Therefore a 250 watt linear is as big as most people will need to run. One very valid reason to need more power is the interferance caused by CB base stations in Mexico where they have no rules concerning Citizen Band output. Many of those stations are 1000 watt stations and depending on atmospheric conditions they can be heard all over North America. Sometimes you need a couple of hundred watts just to talk to a friend 5 or 6 miles away because these foreign stations are putting 5 or 6 S units of noise on you RX meter. Of course having extra channels is very usefull in this situation.
If you are thoroughly confused now I'm sorry. There is way more to CB radios than most people know.
Basically, either buy a radio that can be tuned up a little or buy a radio and leave the insides alone and buy a small linear, 100 watts or so, to run with it when needed. Be smart about it too, dont sit in your yard and blow across your neighbors TVs with your linear and dont key up around cops and you will probably be fine.
Or you and your buddies could get together and get you amatuer radio liscense and and then you would have you choice of many frequencies that you could run a couple of hundred watts or more on legally. However, you have to be mature about amatuer radio as there are some hefty fines if you use it irresponsibly or use profanity, etc.
Good Luck, John
On the subject of amps. They are certainly illegal and the much esteemed former president of the US, Bill Clinton, signed a law that allowed local PDs to enforce the laws of the FCC concerning illegal CB radio equipment. That being said most Cops wouldnt know what they were looking at anyway. You may get caught if you key up an amp when a Cop (no slam intended) is very near you because you may blow over his radio and he will know somethings up. Typically, amps start out around 100 watts. Having the option of flipping a switch to bump up your power to 100 watts is very nice. 100 is plenty for most anyone. The only limit to how much power you can run is how much your battery and alternator can support. I run a 250 watt amp. I rarely ever use it. The only time I do is when I am talking with someone and the terrain or range begins to cause a problem. Then I usually turn it on to finish the conversation because once the signal starts to fade it goes very quickly. The mile per watt number is not accurate. 200 watts is not going to get you 200 miles. To put this simply if 4 watts goes 4 miles then you will need 16 watts to talk 8 miles then you will need 256 watts to talk 16 miles. You get the idea. Of course all of this depends on terrain and other conditions. These numbers are not exact but the idea is that you have to pretty much square the power output to double the distance. Therefore a 250 watt linear is as big as most people will need to run. One very valid reason to need more power is the interferance caused by CB base stations in Mexico where they have no rules concerning Citizen Band output. Many of those stations are 1000 watt stations and depending on atmospheric conditions they can be heard all over North America. Sometimes you need a couple of hundred watts just to talk to a friend 5 or 6 miles away because these foreign stations are putting 5 or 6 S units of noise on you RX meter. Of course having extra channels is very usefull in this situation.
If you are thoroughly confused now I'm sorry. There is way more to CB radios than most people know.
Basically, either buy a radio that can be tuned up a little or buy a radio and leave the insides alone and buy a small linear, 100 watts or so, to run with it when needed. Be smart about it too, dont sit in your yard and blow across your neighbors TVs with your linear and dont key up around cops and you will probably be fine.
Or you and your buddies could get together and get you amatuer radio liscense and and then you would have you choice of many frequencies that you could run a couple of hundred watts or more on legally. However, you have to be mature about amatuer radio as there are some hefty fines if you use it irresponsibly or use profanity, etc.
Good Luck, John
Actually, the manufacturers design the radios to run at 4 watts because of the FCC rules, but most radios are designed with components that will output up to 20-25 watts. This is so the radio doesn't over-drive and over-work the components, thus they will last longer and the output signal will be clean. Since the radios are designed this way, if you know how to mod them, you can get more power out of just about any radio.bigd9247 said:
As for amps, if you want to run one, be aware that it is completely against the FCC rules to do so. I run one and it comes in handy from time to time.
Be aware that there are different types of amps and designs. The best type of amp to get is one that is rated class AB-1, which is the cleanest type of amplifier. Some are class B or C, and their signal starts to get dirty, which causes interference.
There are common amp manufacturers like Palomar, Texas Star, Messenger and others. The amp that I bought is a custom made design by No Name Amps. Check them out - www.nonameamps.com
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The point of having an amp is to use it when u need it. Not to have it on all the time so you interfere w/ other conversations. Although some people do that.afcajun said:
But I've never had a problem w/ it. If someone is hogging the channel there's always a good driver out there w/ a bigger amp to shut em up. And once the jerkoff figures out his amp isn't the biggest on the channel he "disappears". If you get one to use courteously and appropriately, its fine. it's the people that use the to annoy thats bad.
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well compare that to your Taco's engine. 150hp... well cut the exhaust at the cat, throw in a K&N filter in place of the stock or replacement, etc. viola! you've just peaked and tuned your engine. lol ok so our truck is capable of more than 150 hp but toyota put limiters in the system for various reasons. same is with CB's. theyre capable but limited by the manufacturer.Yeti said:
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mine as well add my .02 in here too
if u want a good basic cb to fit a small space for little money and can get it tuned to about 15 watts, go with a cobra 25 ltd classic. next step is basic cb wiht alota options, like echo, etc. etc. an want a lil more like 20-25 go with the cobra 29 ltd classic. amps from my experiance are often not worth it, if ur too close they are distorted and cracky. i have a galaxy dx33 and with my liscence it talks more than far enuf, i dont run no "box" as they are called. i have no complaints with it at all, just wish i had sumwhere in my taco to mount it, considering it is about the size of a cereal box i cant find nowhere.... my advice i stay away form amps, run barefoot and get ur radio tuned and peaked by a professional.
if u want a good basic cb to fit a small space for little money and can get it tuned to about 15 watts, go with a cobra 25 ltd classic. next step is basic cb wiht alota options, like echo, etc. etc. an want a lil more like 20-25 go with the cobra 29 ltd classic. amps from my experiance are often not worth it, if ur too close they are distorted and cracky. i have a galaxy dx33 and with my liscence it talks more than far enuf, i dont run no "box" as they are called. i have no complaints with it at all, just wish i had sumwhere in my taco to mount it, considering it is about the size of a cereal box i cant find nowhere.... my advice i stay away form amps, run barefoot and get ur radio tuned and peaked by a professional.
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