|09-27-2011 03:40 AM|
That would be a complement and if you were a ham operator, you would understand.
I have a full length, 102", quarter wave whip. I call it a big a$$ antenna because...well...it's big. Originally it was on a ball and spring mount just behind the fender flair on the passenger side in the rear quarter panel. Then I got a Congo Cage rack system. So I converted the plastic piece that holds the ball to the side of the jeep to a feed through with just a small amount of adjustment and mounted the spring from the original ball and spring to the rack. Works great. But looks bad a$$. I may eventually go with a Wilson flex stick, slightly better than a firestick. The firestick ain't no slouch either. The Wilson with a spring mount will probably fare better in the bush so to speak, you know.....the alter ego living place of the jeep.
BTW, all of my ham friends poke fun with me for having it on my jeep but, they are the ones who do don't get the jeep thing. It is required by jeep clubs to participate in outings. It was the first antenna on the jeep....before my ham antenna went on there. I wanted to get her out on the trail ASAP and could wait to get the other system in.
|09-27-2011 01:06 AM|
If I remember correctly, 3 db and it being on a logrithmic scale is equal to a 50% reduction. That doesn't seem like a lot, but say you can only transmit a mile or a half mile with a cheap system, then you will end up with half. You can take a transmitter and receiver and they are always only as good as your antenna. I appreciate the top load antenna's and make sure that you are using an antenna that does not require a ground plane. This was well posted above. I did a mod in my 2010 JK and mounted a full size Model 29 on the dash. Really nice setup and some after market parts made it a clean setup. I have talked with a 4' firestick as far as 10 miles. The one I selected was the 50 anniversary Cobra. Sweet display and had the weather bands and will scan and has the built in SWR meter, although pricey. I found a great setup at Cooltech for the antenna setup and there is a great post on the forum for the install on 2010 and earlier. Here's the link to Cooltech and I'm only providing this as a source. I did add a spring mount and quick disconnect. Make sure on the quick disconnect to use electrical grease. Works great for car washes etc.
I wonder if any one has installed a full size CB in the new JK and a good location?
Cool Tech LLC. JK Ultamount CB Antenna System
Oh...a dipole antenna tuned for the mid frequency would be the best setup and Keith is correct on the power. I have got a 1/2 watt transmitter to transmit clearly at one mile with a dipole antenna setup. The most important thing is alway the antenna, don't skimp here.
|09-03-2011 08:45 AM|
The CB tuners who crank up the output of a CB from 4 watts to 5.1 are yielding NO noticeable increase in transmit range but I should probably keep that a secret, ea?
- Keith -
|08-31-2011 10:59 PM|
|08-31-2011 09:26 PM|
SWR means Standing Wave Ratio and is an abbreviation for VSWR (voltage standing wave ratio) but that really doesn't tell us much.
An SWR of 2:1 or less is OK for most modern transmitters. Adjust your antenna so you have an SWR of 1.5:1 or lower on a middle channel. Check Channels 1 and 40 to see if they're 2:1 or less. Tweak the adjustment to get the whole band within range, then lock things down and go wheelin'
There is a LOT of antenna BS and mis-information out there. Even many ham operators are confused about antenna and transmission line theory and operation. Fortunately, most CB systems will work just fine if installed carefully and adjusted for acceptably low SWR.
- Keith -
|08-31-2011 08:26 PM|
You don't have to bother drilling and mounting a fixed vehicle unit and separate mic and have it dangling down or banging your legs or passengers. Lockable in console or remove from vehicle. Works great at trailheads and talking to vehicles when you are outside your vehicle winching etc.
|08-31-2011 08:12 PM|
In post #20 I defined SWR. That definition you can take to the bank.
The reason that high SWR is bad is that it means that the antenna feed point (the usual place that this occurs) if reflecting part of the transmitted signal back at the transmitter final amplifier. When that happens, heat builds in the amplifier. When the heat becomes too great the final amplifier transistor becomes a conductor rather than a transistor and the transmitter stops functioning. The only way to correct the problem is to replace the final amplifier transistor(s). In most cases that is more expensive than buying a new transmitter so you toss the old one and get a new one. A transmitter will generally still function even with an SWR of 3:1 except that your transmitted signal will be small and you will have more difficulty communicating. Most modern transmitters have built in protection circuits that will indicate on the display that there is a high SWR and automatically turn the transmitter power down so as not to destroy the output amplifier. You could say that they are mostly fool proof these days. You will still need to correct the high SWR though before it will work right. Remember that if it has high SWR in transmit it will also be ineffective for receive as well because the signal coming from the antenna going to the receiver will be degraded for the same reason as the transmitted signal is degraded.
|08-31-2011 02:54 PM|
|08-31-2011 02:14 PM|
Just want to toss it in, since new guys may be reading all this. Whatever you do, make sure you get a No Ground Plane (NGP) antenna if you want to have freedom in where you mount your antenna. Otherwise, you will have to mount it on a surface that provides enough metal to properly bounce the antenna signal. With an NGP antenna, you don't have to worry about having a reflective medium to bounce the signal off of. Read up on NGP if you don't know what I mean.
|08-31-2011 01:59 PM|
|3JKs1H1||Regardless of brand, IMHO the most important thing is to check it out before you hit the trail. Hop on the freeway, turn to channel 19 and make sure you can hear truckers clearly. Then transmit and see that they can hear you clearly. It seems as if about half of the people that get CB's don't check them out ahead of time (mounts, grounds, planes), and that makes a larger group wheeling - well painful.|
|08-31-2011 01:46 PM|
|08-31-2011 01:07 PM|
|08-31-2011 01:02 PM|
Basically it measures what the radio is sending out to the antenna vs. what the antenna is sending out thru the air. Ideally 1:1, realistically under 2:1 is acceptable. Lower is better. Too high and you can burn up the finals in the radio.
|08-31-2011 07:50 AM|
I agree better/longer antenna would be ideal but for me i did not want a huge antenna. I am sacrificing for sure but I am happy with the result from about $25 in junk.
I decided that if when i wheel with people thay have to stay under ch 25. LOL!
Basically my point was to make sure your meter your setup no matter what. I was burying over 2.5.1:1 when I first hooked it all up. I would have wrecked the transmitter very quickly.
Just for people info this is what i am using to meter.
Very easy to use. Mine i got at a garage sale for $10. There are better more expensive units out there as well.
|08-31-2011 12:30 AM|
Your SWR looks OK to me. It would be a bit flatter if your antenna was 102" 1/4 wave whip but that looks pretty good.
|08-30-2011 11:57 PM|
Just setup and tuned my cb setup. It's basically all junk i found at garage sales except for my RS SWR meter.
Metered at 1.2:1 on ch 20 It gets worse(1.6ish:1) on the 30-40 channels but if i stay under 25 I can get really clear transmit at 3 miles in town. Thats with a 36" 5/8wave antenna mounted in my stock 3rd brake light. Rcv is about the same. I did have to trim my antenna a bit to get it right. 1.1:1 is hard to get without perfect conditions from what i've seen.
The metering is more important than the hardware. You can get better transmitters and antenna setups but for trailing, simple is usually best.
|08-30-2011 11:23 PM|
|08-30-2011 11:20 PM|
|08-30-2011 09:41 PM|
hey, what did you guys do with you extra coax? loop it under the seat in the back? Just wondering.
|08-30-2011 09:21 PM|
.... now where'd I put that Conway Twitty 8-track ... I was hoping to play that in my new 8-track player install I just completed on the Rubi ...
|08-30-2011 09:05 PM|
I used these guys long ago. Jeep & Off-Road CB Radio Kits
Real helpful and even looked at my order and knew i forgot a stud and threw it in. I had mine mouted on the windshield in my 2007 using the small Uniden or was it Midland or Cobra. All pretty much the same. Project JK kind of outlined it for me and was easy to follow in the install. Project-JK.com - Jeep JK Wrangler Resource » Affordable Jeep JK Wrangler CB Radio SolutionMidland Model-1001Z
probably don't need it anymore, but thought it might help.
|08-30-2011 08:58 PM|
|06-10-2011 10:43 PM|
|jk'n||The mount seems a little on the high side for what it is but I would purchase it given that, if you did find one cheaper, it probably won't be half that price and the amount of time you will spend finding it may not justify the cost differential. The mount point in front of the spare is acceptable. That is where my ham radio mounts are on an Arizona Rockie Road mount. That mount puts the antenna up a little higher. For a CB antenna, it may be better a little lower. But people do put them on that mount. I have the dual mount set up on mine.|
|06-10-2011 10:16 PM|
Wowzer JK'n--thanks. I'm going to need to digest all that and then come back with questions.
Given the relatively low cost of getting in on the ground floor here, I think my best option is to pick a reasonable base set up and just give it a go. Questions will follow naturally after that, and I may very well end up swapping out one part for another etc. down the line. If you approve of my current proposal for the basics, then that's what I'll go with.
I agree with you on the TeraFlex mount. I think it's ridiculously priced for what it is. Looks like a $5 to $10 part tops to me. However, I wasn't able to find a cheaper, no-drill, JK specific option (thereby ensuring that, even in my topical ignorance, it would work). Wilson's CB (I believe) had a JK "package" (with a Cobra 25) that included a near identical mount for $5 MORE.
Perhaps some more time on Amazon is in order. I suppose I could fab something up too.
And really--thanks everybody. I started today knowing nothing about CBs and am feeling a lot better about it now.
|06-10-2011 09:26 PM|
|jk'n||My cheap $30.00 CB gets me 2 to 4 miles depending on granite. Good enough for trail communications.|
|06-10-2011 09:20 PM|
|CajunTiger||Being an "X" cross country truck driver, I prefer a Galaxy CB. I looked at the newest they have and it is a little pricey, but it goes alot further than a $30.00 CB. If you spend that on a CB, I hope someone is within 1 mile of you, cause nobody else will hear you. Ok for "Gang Bangin' " the trails, but if your alone and trailin', I would like to have some range....jmo....|
|06-10-2011 07:53 PM|
I checked out all of your choices and think them solid. I say this knowing quite a bit about what I'm talking about. I hold a ham radio Extra class license, General Class commercial radio-telephony Federal License and Master Electronics Technician license in MA. Plus licensed to teach Electronics in MA. You can take what I say to the bank. I don't claim to be a no-it-all and as with anything, there are personal choices to make.
I'll start at the top of your list.
1. Any 40 channel AM only CB radio sold as is new and over the counter (not modified in any way) puts out the legal limit in terms of power which is 4 watts. This is covered under Eligibility in this link. Some CBs claim higher power but if you read the fine print you will see they are referring to audio output not output at the antenna jack. Your choice will work as well as any other of higher price. Most of the higher price is smoke and mirrors.
2. Your coax cable will work fine with the Wilson antenna and it is the antenna I would choose if I didn't want the 1/4 wave whip that I have now. Follow this link and under fiberglass antennas check out #5 that speaks about coax length. My understanding is that the firestick requires 18 feet of coax because it is necessary to match the impedance of the antenna at the feed point. On a firestick, the coax should not be trimmed from this length, rather the excess should be coiled up and stored in an inconspicuous place. I'm not sure if the same applies to the Wilson antenna. The Wilson antenna is a straight line antenna (not a coil type antenna like the firestick) and is, according the the Wilson web site a top loaded antenna. That should mean that the top loading makes up for the fact that it not quite 1/4 wave in length and should match the impedance of the coax at the feed point. Long story short, the length of the coax should not matter as much on the Wilson. I would still leave it at 18 feet just in case you may want to try out a firestick at some future date. My coax is 18 feet even though I am certain that it's length doesn't matter in my installation.
3. I currently have a 1/4 wave whip. It is 102 inches long and contacts all low flying objects and is a pain in parking garages so I have to tie it down when in the city and planning to park. The 1/4 wave whip is the best performing antenna for CB on a moving vehicle. Land stations may use a 5/8 wave antenna but that is not reasonable for a moving vehicle. Moving to shorter antennas from the 1/4 wave are all compromise antennas and the general rule of thumb is that the shorter the conductor of the antenna below 102 inches, the less effective it is. The Wilson, even though I could find no facts on gain on the Wilson site, should perform better than the firestick. I'm planning on getting one to test it out. I have a firestick and never use it.
4. The mount point is a matter of personal choice for the most part. The one that you have chosen will work well. For what is pictured, a bent piece of metal with some holes drilled in it and painted rather than stainless the price seems a little high. But absent an alternative at a lower price, it is acceptable.
The package price seems reasonable for all of the items that you have selected.
After you get the installation done you should bring it to a place that installs radios and have them check the SWR. They will know what to do. If you plan to do it yourself then here is some information. Antennas are a resonant device meaning that under ideal conditions, they operate at peak performance in the very center of the band and for CB that is approximately channel 20 give or take a small amount (the frequencies are not consistently spaced from 1 to 40).
SWR stands for Standing Wave Ratio and is the ratio of voltage maximums to voltage minimums along the length of the feed line. Pretty complicated huh? The ideal standing wave ratio is 1 to 1 meaning that the voltage is the same along the entire length of the feed-line. The best SWR in practice is considered to be 1.1 to 1. Standing waves occur in any medium in which sine waves may be traveling in opposite directions. This happens in oceans when the wind is traveling in the opposite direction from the water (tide). While swimming in the water there will be places that you will be moving up and down a lot (a place of maximum amplitude) and other places that you will see the water moving up and down but you are not moving up and down (a place of minimum amplitude). Maybe you have experienced this in a boat? In an antenna circuit any place where there is an impedance mismatch is a place where signal sent down the line is reflected back at the source. The most typical place where this occurs is at the place where the antenna connects to the feed line. The feed line is built to have an impedance of 50 ohms. All antennas that connect to transmitters in the US (for the most part) are built with a 50 ohm output and a 50 ohm impedance coax is connected to it and a 50 ohm antenna is connected at the other end. And when that happens, all is good and the SWR is 1.1 to 1. The antenna sometimes has to be trimmed to create this balance on channel 20. So, the swr meter is placed in the line at the transmitter. The transmitter is keyed (transmit button on microphone is pressed) and the SWR is measured on channel 20. If it measures approximately 1.1 to 1, you are done. If it is not 1.1 to 1 then it needs to be determined if the antenna needs to be shortened or lengthened. It the antenna has an easy method of adjusting this you just use trial and error to correct its length.
The reason this has to be checked is that if there is too much signal being reflected back at the source (high SWR), heat will build up in the final amplifier of the transmitter and eventually the circuit will fail and in today's market that will mean replacing the transmitter because that will be cheaper than having it serviced to replace the broken part.
|06-10-2011 04:42 PM|
Basically, you are adjusting the output power against how much is being "reflected" back to the CB. Typically a 10:1 (forward:reflected power) is good, but with some "tweaking" you should be able to get it lower, 10:0.5, or so.
Also, tune it using the primary channel you will be using. Down here. we use channel 12.
|06-10-2011 04:32 PM|
In short.. Awesome radio that I would recomend to anyone..
|06-10-2011 04:26 PM|
Okay folks--how about:
(1) Midland 1001Z 40-Channel CB Radio'
(2) Firestik Coax with low-profile fire ring and stud
(3) Wilson Flex Antenna
(4) TeraFlex mount
Comes out to about $110 plus shipping.
Also, will the Firestik coax work with the Wilson antenna, or are the connections manufacturer specific?
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