Question on Dual Antennas?

[PUFF00]

Is using 2 antennas really worth it? How do you connect the coax to the CB?

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2001. 5 3500 QC 4X4 6-speed HO 3. 55 black
1998 Jeep TJ black http://www.nm4w.org/members/puffer.htm

 

[mongoose]

dual antenna work great. some people swear by them, but i prefer a single. One thing i have noticed about dual's is that they are more directional (forward and back) than a single. About the coax, most large truck stops and CB shops carry dual antenna coax. This has a single connector on the CB end and splits in to two coax lengths for the antenna ends. Hope this helps, if not i'll snap a picture and post it this weekend.

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Daniel McKeehan
1999 2500 QC/Short Bed/4X4 5 speed. Camper Package and of course a Cummins.

 

[Cooker]

Like mongoose said dual are more directional, maybe not front to back but definitely side to side. They do nothing for the range itself.

 

[Okie-Go]

I don't have a cb but the dual rabbit ears sure look good going down the road on top of a ram.

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2001 quadcab slt 2500 HO 6spd. LWB,2wd,dk garnett red, trailer tow package,camper special, anti spin 3. 54 axle, speed liner,oversized stainless steel chicken slide,66 gallon in bed aux. tank,K&N air filter,Reese 20k hitch, Terry 2000 EX 30ft. double slide 5er, 2000 20ft gooseneck for haulin jeep, firewood and huntin stuff. 5X12 tagalong for haulin the 4 wheeler. Okie Newton

 

[frijole]

Horsepucky, get a single roof mount Wilson 1000, over at Mesa CB, corner of University and Menaul. It'll do all you'll ever need to do. Even the Ham guys use this antenna.

 

[Ted Constantine]

I recently asked a person very knowledgable in the subject this same question. The response suprised me. He said that unless the antenas are a full 9 feet apart they are actually much less effective than a single. He also said that even at 9+ feet they have to be constantly tuned and are high maintenance. The moral of the story seemed to be that it is not a good idea on anything less than a big rig and questionable on them.

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2001. 5 2500, quad cab, 4X4, ETH/DEE, 4. 10 LSD, 255/85 BFG MT, BD Exhaust Brake, JRE 4" exhaust, EZ w/ elbow, 275's, SPA, Amsoil Dual Bypass Filter, Amsoil under the hood (soon to be everywhere else), Leer topper, Piaa driving 510's in bumper, Line-X, Stereo= JVC KD-MX3000, MBQuart 6. 5 components in front doors, 6. 5 coax in rear, JL Audio Stealth Box sub in center seat, Fosgate 400a4 and 250a2 amps, DynaMat everywhere

 

[mongoose]

i agree frijole, wilsons are great antenna's!

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Daniel McKeehan
1999 2500 QC/Short Bed/4X4 5 speed. Camper Package and of course a Cummins.

 

[Big_Bad_Dually]

I'm with Ted. The only reason for dual antennas is for the tall trailers like Bull Racks, Reefer Trailers, and tall campers. It is easier for the signal to go around the trailer with duals.

If you are after looks put two antennas on and only hook one up. #ad
I'm running a Larsen NMO mount roof antenna (must drill 3/4" hole in roof to mount).

Brian

 

[Forrest]

I used a magnetic base, base load, approx 4' long, on the cab right over the outside break lite. 100 watts on 10 meters did East coast & Hawaii. #ad
Got it @ Radio Shack.

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Money Sink - 96, 5 speed, TST 380, HX40-16, 300 HP Injectors, Scourge BD 4200rpm Governor kit, McLeod, 4", CATless, straight out back, chrome turn down, ISSPRO Pillar, Delvac 1 & Amsiol, K&N, Mag-Hytec, 3:54, Michelin 235s on Alcoas, Rancho 9000's, Valentine One, Garmin.
Dutchmen 27' 5th Wheel.
GoldWing.

 

[PUFF00]

Thanks for the info. I’ll stick with a single roof mount. I’ll probably have to get a magnetic mount so I can get in the garage.

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2001. 5 3500 QC 4X4 6-speed HO 3. 55 black
1998 Jeep TJ black http://www.nm4w.org/members/puffer.htm

 

[Shovelhead]

Just a word of caution on the use of magnetic antenna mounts. If you have the overhead console with the compass feature, you may screw up the calibration of the compass by using a magnet on the roof. Check the factory "bible" or your owner's manual on this.

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Ed Anderson
99 3500,6x4,QC,Auto,4. 10,Everthing 'cept leather,stock until warranty runs out.
'76 H-D FLH, '98 FLHTCUI
"Never ride faster than your guardian angel can fly"

 

[NWright]

A word of caution on mag mounts. It you leave it in the same place and don't keep the underside of the mag. clean you can end up with paint damage. They are high enought so that you can't get in the garage without removing . What I did was made a place on the bed rail behind my tool box and made the coax long enough so that if I want to reach out or when I pull my 5th wheel I can put them on the cab
nathan



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Nathan Wright

2001. 5 2500 QC auto 355 4" from Resonator back,TORO-Line gauges,D-Celerator exhaust brake, Tool box with a 24 gal tank under it, 2meter and CB radio ,GPS III interfaced with Toshiba Satellite 2100 laptop, 5000 watt generator. Pull a 30 ft Shadow Cruiser 5th wheel and a 18 ft bass boat.

 

[C Schomer]

I read once, that cophased antennas are NO benefit unless they're at LEAST 94" apart. Position(relative to the groung plane)and getting the SWR down is WAY more important! Craig

 

[ynot]

Dual antenna's make it impossible to get the SWR under 2. A good single can get you to 1 or even . 8 (only seen that once). The 8ft. stainless whips work best for distance, but look goofy. Firesticks (adjustable) have 5/6th the output of a Wilson, just doesn't look as good to the truckers. The Wilson 2000 is easier to adjust than the 1000. A good coax is the gray outdoor RG58 with the screw on ends. Use di-electric silicon grease in the boots. I tried RG8 ham radio coax (the fat stuff) and it sucked. Good for FM business bands, but not a CB. Both single and dual coax have to be cut to the exact length. A CB shop can help with that. One of them is 32', but I can't remember which. Mine is buried or I'd measure it... T

 

[Wiredawg]

I have dual truckers and my SWRs are 1. 2. I like them being directional because I use it mostly when I'm running up and down the highway. I have this setup on both my Rams and they both work great.

Wiredawg

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2000 4X4 SLT QC 8' bed; 6 spd, 3. 54 ; BD exhaust brake and 4" exhaust syst; TST PM2; Airlift Super Duty rear air bags; RS 9000 shocks; pyro/boost gauges in 2 gauge a-pillar mount; back preasure gauge mounted under dash; KN air filter; Brown's Welding brush/grill guard, rear bumper & headache rack; nerf bars and aluminum roll top rear cover, Warn front receiver and Hadley air horns, 20K Reese hitch,Mag-Hytec dif cover,Psycotty Air.

 

[Hammer]

Anyone with a knowledge of antenna theory can answer this easily,,Since the width of our beloved Rams is not OVER 96 inches a cophased antenna system is NOT needed,,These systems were designed to correct a signal pattern created by the height and length of most semi's,,It corrects a blind side condition that exsists in most of these applications,,So as far as a antenna system for your ride,Wilson is the easiest,magnetic or roof mount,,Also they do outperform their K40 counterparts by a large margin,,Fit in your garage,twist the top on my 5000 and of it comes,and install the protective cap,,Power you ask,a old President grant export,100 Texas Star modulator to kick my Sweet 16(1600 watts),So they will handle what you need,,As far as cophased antenna's I'm not saying they do not have their place,but a well placed single antenna will outperform a cophased system,,Hard to tune twins,not true they can and have been tuned lower than 2. 0... ... .

 

[TXRam]

I have dual Wilsons (liked the look) - buddy has single Wilson roof mount. We have compared our reception driving down the road together and couldn't tell any difference in reception/transmission (exact same CB's). FWIW.

 

[PRout]

Nothing beats ONE 102" 1/4 wave stainless steel whip mounted directly in the center of the vehicle (on metal) as high as possible.

Dual antennas can actually degrade the signal due to phasing.

WB6BFD

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2k, 30k miles, QC, SB, 4x, 6sp, 3. 54, 285/75r16 bfg/at, stock air cleaner (reliable), silencer ring "in" (runs better), Sunnybrook 28' fiver, 16,780 lbs. 18mpg (unloaded), 12-14 mpg (loaded). VA, DD1's, PS Boost module & elbow, BD brake... also, Nitrous Oxide piped direct into the block (stealth - to keep the warranty), 10 gallon per minute fuel pump, ECM right out of Don Garlit's Top Fueler (he gave it to me) (for letting him ride in my truck), Super Modified DD1 Injectors ("Hand Honed" with a 1/4" reamer & my 12v Makita). More BOMBING to come. .

 

[Wiredawg]

Hey guys:

I may be displaying my ignorance on antennas here, but what the hey?

I agree, the best mounting location for an antenna is the center of the roof because it's a good ground plane and it radiats in all directions. Negative is height clearance.

Mounting to center of tool box behind bed will radiate mostly forward due to ground plane being mostly in front of antenna. Height and radio direction can be negative.

Mount single antenna to side of vehicle: side mirror, door cab etc... Antenna will radiate in a diagnal direction.

Dual mount on side mirrors/doors. Radiates front to rear mostly with ok side to side reception/transmission. Good height clearance. I somewhat understand the co-phasing issue, but still find the set-up works well given the truck height limits on my truck.

OBTW, I once had a 102" whip on the center of the roof of another truck: Used to take out flourescent lights at gas stations. #ad
#ad


Any experts, please correct me if ah'm wrong.

Wiredawg

 

[Shawn.L.Turbo]

Well, since I work in the radio engineering field, I guess I should pipe in here.

Co-Phased antennas ARE a benefit ONLY if the spacing is adequate. Our RAMS are NOT wide enough to do this. The spacing needed for co-phasing antennas is based upon the wavelength of the frequency being used.

I must correct something said earlier in previous posts. It was said that co-phasing gives directionality but no additional gain. Untrue. Gain actually COMES FROM the fact that it is directional. Think of an antenna system like a magnifying glass and the sun.

If you focus the energy in any direction (just like burning bugs with a magnifying glass and the sun)the heat grows hotter and hotter, right? This is because LESS of the energy is going in other directions.

Big rigs can barely get away with co-phasing, and only then if it is done properly.

I have spent years playing with antennas for all kinds of frequencies, and I'm here to tell ya, that without very careful tuning, and placement, you won't realize the benefits of phasing.

I am a ham also, and have even stacked 6 element yagis (these things are HUGE!!) on towers.

Bottom line, stick with a single vertical with a really good ground plane, and you will be saving yourself a lot of headaches, and you will also most likely realize better performance.

Cheers,

Shawn
VE6PV