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Old 04-25-2018, 04:42 PM
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Post Example CB Kit

I did a fair bit of searching on the net and forums here before trying to put together my kit, but even then I came across a few missing pieces after I had ordered everything. My goal with this post is to help someone totally new to the concept understand all the pieces that *might* go into a build. Of course, find your own parts, make it yours, but this build worked for me.

Parts that I used:
I would recommend getting a stranded core coax cable though. I routed the coax cable through the doorjam by the windshield corner armor plate (actually under the plate under that plate), tucked under the dash just inside the door, and then up underneath the passenger's footwell under the carpet, into the center console area then along the baseplate and up into the armrest console, where I drilled a hole in the front wall to pass the connector through. This lets me put the CB and mic hidden in the center console when not in use. The L coax connectors allow me to sit the CB lower in the console without potential damage to the coax cable.

I also (because I enjoy solder work) took apart a very small USB car charger, desoldered all the bits on the control board, clipped part of the USB adapter itself to allow wires to pass through that opening, and then soldered the power leads from the Uniden directly onto the adapter (black to ground - the outer side bendy pins; red to live - the springy tip pin). If you're not good with a soldering iron or don't want to risk it, you can get something like this adapter and just screw the wires onto the exposed terminals. Important note though, the 12v plug inside my center console is connected to the battery, not the ignition, so the CB needs to be powered off or else it could drain the battery.

Attached is the full antenna/coax wiring diagram with the parts labeled so you can see how they all go together since I couldn't find anything like that on the net.

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Old 04-26-2018, 09:37 AM   #2
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Lose the spring, it's not really needed with a 4' antenna.
The bigger issue is using the spring along with the disconnect can make tuning difficult. You are lengthening the antenna quite a bit when both are used.

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Old 04-26-2018, 12:33 PM   #3
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Lose the spring, it's not really needed with a 4' antenna.
The bigger issue is using the spring along with the disconnect can make tuning difficult. You are lengthening the antenna quite a bit when both are used.
X2 on all of that. I stopped using antenna springs many years ago as they're seldom needed and they can make tuning the antenna far more difficult by making the antenna electrically longer.
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Old 04-26-2018, 12:58 PM   #4
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Further critique of the "example" system:

I am no fan of the Firestik quick disconnects, although they are better than the garbage quick disconnects found under the Workman brand and some of the other pot metal bayonet style disconnects found on Ebay, etc.

Here is a little known option that combines an antenna stud mount with a solid brass disconnect (a bit spendy but very high quality):

With ring terminals for coax:



Or use a SO-239 connector:




See: https://www.breedlovemounts.com/qd-antenna-mounts.html


As for antenna springs, I recently changed up my antennas and mounts and no longer use a spring with my 4' Firefly antenna. I would, however, still use a spring with the stiffer 4' Firestik II.

There are areas where a spring will not be necessary with a 4' Firestik II, but the overhead obstacles where I typically offroad warrant the use of springs with stiff antennas.
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Old 04-30-2018, 09:52 AM
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Good feedback, all!

While attempting to tune the setup, I found that the best performance was without the quick disconnect, spring, and even the f/f joiner, connecting the antenna straight into the so-239 stud. Keeping the qd in however was lets me stay with an swr of 1.5-2.5 (depending on channel) so it's not great but not horrible. The spring adds another 1-1.5 swr on top of that. Lesson learned is that, everything you put between the antenna and the radio is going to increase (hamper) SWR.

Also, I don't think anywhere mentions that the Firestik II does NOT have a tunable top-end like the pictures suggest.
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If/when my parts fail, I'll look into those brass connectors you showed. I like that idea, looks sturdy. Is there a noticeable difference between using SO-239 and Ring/Terminal connectors?

I went with the SO-239 only because I hadn't come across the Ring/Terminal idea before buying the cable I used. At some point in the future I'll upgrade to a stranded coax cable and switch over, but for now I figured the SO-239 is easier than trying to create those connectors myself by cutting off the end of my coax.
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Old 04-30-2018, 10:29 AM   #6
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. . . I don't think anywhere mentions that the Firestik II does NOT have a tunable top-end like the pictures suggest. . . .
Au contraire. The original Firestik "KW" series antennas are "cut to tune," the Firestik II "FS" series, Firestik II "USA" and Firefly antennas have tunable tips, and the Road Pal series of budget antennas are "cut to tune. See Firestik Antenna Company Home Page.


As for the difference between using an SO-239 connector or ring terminals, the SO-239 works just as well and is easier to use for the average consumer as you noted. I typically use ring terminals at the antenna end only if I have to fish coax through tight spaces where an SO-239 won't fit.

In my jeep I could have easily used a commercially made length of coax with SO-239 connectors on both ends but I had a long enough piece of coax with the ring terminals already installed so I used that rather than purchase an additional SO-239 adapter and/or 90 degree fitting. Besides, the ring terminals illustrate how the center wire connects to the antenna and the braided shield connects to ground in an antenna system.
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Old 04-30-2018, 11:06 AM
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Au contraire. The original Firestik "KW" series antennas are "cut to tune," the Firestik II "FS" series, Firestik II "USA" and Firefly antennas have tunable tips, and the Road Pal series of budget antennas are "cut to tune. See Firestik Antenna Company Home Page. ...
Thanks for that. I actually have the KW not the II/FS. Perhaps I'll attempt cutting to tune next weekend when I have some fiddle time. I am curious though, why the spring tends to be so bad for tuning. Isn't bigger/longer better for radio antennae? Does it add to the length only because of the ~3" height or because of however many feet of wiring are curled up?
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Old 04-30-2018, 12:08 PM   #8
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Thanks for that. I actually have the KW not the II/FS. Perhaps I'll attempt cutting to tune next weekend when I have some fiddle time. I am curious though, why the spring tends to be so bad for tuning. Isn't bigger/longer better for radio antennae? Does it add to the length only because of the ~3" height or because of however many feet of wiring are curled up?
When you trim the wire for the KW series, only snip very short lengths off at a time or you may find that you have cut too much off and the antenna will not tune properly to a good low SWR as is required for it to put out as much power as the CB is capable of providing.

Antenna length is critical, too tall of an antenna for transmitting is as bad as too short of an antenna... either will cause the antenna to not be tuned properly for the frequency being transmitted on. So yes adding a spring to an antenna can make it harder if not impossible to tune properly due to the spring adding not only physical length but electrical length too.

The proper antenna length depends on the frequency it is being used on. High frequency antennas need to be shorter than low frequency antennas are.
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