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Has any one out there tried hidden antennas in there bike . I have been searching for them on the web and found that some people have tried them but they do not give out much info on how they are working . The reason why I am asking is I think they are a great idea if I could put them in the faring and get them out of the the way. Info on where to buy would be a great help.
 

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I dont think they make them for a CB, totally different frequencies, and it needs to be tunable for the CB. The Street Rod industry has used the hidden FM antennas for years. They dont function as well as a regular antenna, but they do ok.
 

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I don't think the technology exists for cb's.

But for the radio you can make your own. Go to radio shack and purchase a plug to fit the antenna port in yer radio. attach a decent length of 16 awg speaker wire to the contact points of the plug. Run that speaker around the inside of your faring. Simple but works.
 

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I did that on my Yamaha, it works as good as any little rubber ducky antenna. About 39" would be the close to the ideal length for FM.
 

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I like the idea of making my own for the FM antenna . Why couldn't you make a CB one to try . I am going to look into that .
 

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There is a way to make a hidden CB/Ham antenna, and I will attempt to explain. First aquire an SO-239 antenna connecter, it's the peice that is on the back of the CB, that the coax screws on to. You can buy one at Radio Shack, or find a junk CB, and rob it from there. Anyway, try to get one that is attached to a small square plate, like on most CBs, they are normally attached with rivets. Drill those out and leave the square plate on it, you will need it later. Find a small piece of plexiglass or similar insulating material and drill a hole in the center of it, just big enough for the round part of the SO-239 to fit in to, and mount it loosely. Now assuming that you are using a normal 40 channel CB radio, channel 20 would be the center of the band. Use the magical number 468, and divide, 27.2050 into it. 27.2050 mhz is the frequency for channel 20. You should come up with 17.20, and that is in feet so a 1/2 wave antenna tuned for channel 20 would be 17.20 ft long. To conserve space lets divide that again, by 2, to get 8.60 ft, for a channel 20 1/4 wave antenna. Now take a piece of 14/2 romex or similar insulated wire, (leave the insulation on, we'll get to that in a minute), and cut a piece, 8.60 ft long. Now cut that piece into2 equal pieces, 4.30 ft long. Bare enough insulation in one end of Both wires to do your soldering. Take one end of one of the wires and put it through one of the 4 corner holes we talked about, on the SO-239, and solder it. Take the other wire and solder the bare end of it to the center post of the SO-239, making sure that these two wires can not touch one another. I forgot to say that your plexiglass can be as small as 1 and 1/2" square. Now screw the coax from your radio on th the coax side of the SO-239 and turn the radio on to check the standing wave. The lower the standing wave is, the farther out you can transmit, but if it gets OVER 2.0:1 ratio it could damage your radio, so be cautious. Now the reason we left the insulation on the wire is, as long as it is isolated from any ground, it should work. Please make sure your standing wave is at an acceptable range BEFORE you tape, or zip tie it to your frame or wherever you decide to mount it, keep it from overlapping itself, and as straight as possible, but you should be able to find adequate space for a 1/4 wave CB antenna, somewhere on a Goldwing. Another word of CAUTION ! IF you have extra channels in your radio, like Mine goes 300 channels above channel 40, and 250 channels below channel 1, do not try to use this design, you WILL burn the finals out of your radio, and anyway unless you are licensed by the FCC, transmitting anywhere besides channels 1-40 could get you in hot water. NOTE, if your standing wave is not acceptable, you can ADD to the wire length, or shorten it for tuning, or get an antenna Matchbox, or an SWR Bridge. I will gladly answer any questions, or help in anyway I can, and Yes, I have been licensed by the FCC since 1991,

GOD Bless ALL and MERRY CHRISTMAS

Steve-O (b679995)
 

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Steve-O,

Where does the 468 number come from? The rest makes sense to me. Just some stuff I've forgotten over the years. I'm not going to to do this, just my electrical-oriented mind wants to know...

On a side note, we need to meet up in Clinton or something, maybe not this weekend, but sometime in the spring.

Bill
 

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Hi Bill, I am surprised that I even nemembered the number but, in 1990, when I was taking Ham Radio Classes, this is the number that they. (the instructers) refered to when talking about 1/2 wave signal. You may also find it in ARRL (American Radio Relay League) publications. The antenna lengths get progressively shorter the higher you go up in frequency. Some UHF antennas, for the 1200mhz band may be < an inch long. Makes me wonder who figured all this out.

I would enjoy meeting up sometime, We are still waiting for my wife to heal up from a long term illness, she's been bedfast since April but I sure hope she's back on foot by next riding season, we Love your end of the state, and have been to Branson over 30 times, but never on 2 wheels, I voted for NASSIR 2 to be in Branson, I could have had the Best of Both worlds!

:waving::waving:

Blessings

Steve-O
 

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I'm sure there's a formula for the length of the wave somewhere, I just forgot that stuff. I never really got past CB personally, but the classes I took toalked a lot about full/half/quarter length waves. Just curious more than anything.

Yeah I agree, Branson and south of me are great places to ride. I voted there too.

Prayers go out to you and your wife for strength and healing...

Blessings...
Bill
 

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Well, since we're talking cb's here, I'm trying to figure something out also concerning antenna connectors.

Right now what I have is the Clarion 2 radio system with cb that I'll be installing after the holidays. What I want to do is use co-phase cables running 2-4 ft firesticks mounted on the lower saddlebag light bar, one on each corner. The Firestick antennas I plan to use do have adjustable tips on them for adjusting the SWR.

Here's the problem I'm going to run into with this setup. The Clarion antenna systems all use RCA connectors, including the antenna splitter. So what I'm gonna need is one of two items. I can use a female PL259 to RCA male adapter or an antenna splitter box that has a PL259 female input on one end and 2 RCA male outputs on the other end.

Now which of these 2 options is going to be the easiest to source the parts for? The adpater or the splitter?

I will also be installing a very small 100 watt Linear amp into the antenna system I have, maybe, depending on how I can mount it and still have access to the switches on it. This should help with the transmit range as long as I can get the SWR down to an acceptable level.
 

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Ok, already found the correct PL259 female to RCA male adpater on Ebay for under 2 bucks. Problem solved already.
 

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They are getting few and far between anymore, but if you have a CB shop near you anywhere, I'd check with them. I would run the CB cable as far as you can, then get one adapter to go into the CB. Your linear will probably only use the PL259 plugs anyways. You can get a "Y" cord with enough length to run the entire length of the bike (I think they are 17' if I remember right). With the Linear, definitely start the SWR checks in the middle, but check both ends of the range. Don't leave it keyed up very long until you know its fairly close.
 

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I can get co-phase cables on Ebay as short as 9 ft, no problem, or custom made by 3 ft increments.
 

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B679995 Yes Jesus is my lord and Savior to . Nice to talk to a fellow born again Christian ,especially one so knowledgeable about CB's I think I under stand what you are saying . I am going to try it on my bike . One question ,that so-239 is just the connector that screws the coax in to the CB . Make that two things .Just to confirm the length of the coax including antenna is in portent .
 

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Not to get too picky about the correct length, but 4 ft plus is too short for a 1/4 wave on 27 mHz.

Should be 9 ft. I think you divided by two once to often.

The length formula is derived from the speed of light, somewhere in the 330k per second range. Been too many years for me too. And I'm too lazy to search for the real formula.

That 9 ft length is why you see the loading coil in the middle of all of the shorter CB antennas. The short tiny ones like on our bikes aren't very efficient. That is why you see the monster coils used on the trucker's CB antennas. Larger diameter and coil wire size makes for better efficiency.

But, back to running the antenna behind the fairing. It's not going to work very well as that will make it mostly horizontal. And if you don't insert a loading coil (properly tuned) the SWR is going to be well over 5 to 1. Zap one set of finals in a hurry.

What ever you do, make your tuning periods very short, and keep trying to get a near 1 to 1 SWR match. It will be very difficult as your body moving around the bike is going to change the loading.

No one said it was easy, but it can be done.
 

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YEs John, it takes 2,,,,4.30 ft pieces to make a quarter wave antenna tuned for channel 20,,,, or freq. 27.2050.

17.20 ft = half wave

My memory is not what it use to be so excuse this old Goat !

Blessings

Steve-O
 

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CO-Phase antenna coax are fairly simple to make too, it's to bad they want so much for the pre made ones. I have several big ARRL antenna books, they are a little expensive but have a ton of info! IF I had a stock charging system, which I do, I would not try to run a linear amplifier on my bike, also stay clear of the antenna while trransmitting, the RF is harmful when pushed by an amplifier!



Blessings

Steve-O
 
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