Wanting to impove my Ground Plane

[bulkness]

I had H-D install the CB in our Tri-Glide while it was still in the dealers possession. I am sure the service tech did no more than the instruction shown. I will need to check over the install as the coax was not tight where it mounts to the antenna stud.

I know the ground plane on the Ultras needed improvement to work better. I'm going to take the Tri-Glide to my local radio shop and have him run a SWR on the radio prior to making changes and I'll have him run the SWR after I have made the improvement shown by the forum and the local radio shop tech. I'll report back to the forum on the improvements.

What can I do to improve the ground plane on the Tri-Glide? I know J&M Audio make a kit but it is expensive and not designed for, but will work on the Tri-Glide.

Thanks in advance for any and all help.

 

[dougv]

The frequency that CB operates on, 27 mhz makes it very difficult to install an effective ground plane on any vehicle, much less a trike with a small fiberglass body. At 27 mhz, the ideal ground plane would be 9 foot long radials which is impossible to do.

I remember there was a manufacturer who made antennas for corvettes that were designed to be used with fiberglass bodies and did not require a ground, similar to what a boat would use. I have a Goldwing and the antenna is mounted on the trunk, which is fiberglass. It could be the Tri-Glide and Honda antennas are designed the same way as the corvette antennas. I don't know what the kit is but some people have used copper plates under the antenna but about the best you may get is a heavy ground wire to the frame.

It's a major compromise using a CB on a bike or trike and the range will fall off pretty quick.

Too bad the GMS radios are not more popular because at 450 mhz, the size of an antenna and ground plane is much smaller and will provide greater range with less interference being it is FM.

I wouldn't waste a lot of time and money on chasing this, even the SWR measured can be deceptive and with only a few feet of cable, a higher SWR is not going affect how well the antenna works, unless there is a major issue with the antenna, cable or connector.

 

[bulkness]

Thanks for the information. I'll run a good grounding strap to the frame and be done with it. Thanks again.

 

[tfdeputydawg]

[QUOTE248551]
even the SWR measured can be deceptive and with only a few feet of cable, a higher SWR is not going affect how well the antenna works, unless there is a major issue with the antenna, cable or connector.[/QUOTE]

I would respectfully disagree w/this statement!
Tuning the SWR matches the antenna to the radio. the length of cable has no affect on the performance of the antenna. A high SWR does cut transmitting distance and if high enough can damage the finals in the radio.
On a trike, under the fiberglass body is a metal frame, which helps some but, not much.
Good grounding, Tuned SWR, and replacing the "short" HD antenna(which doesn't have a load in it) will give you the best transmitting distance you can get!

 

[Phu Cat]

Bulkness, I noticed your thread about ground plane and didn't know that was affected by the ground wire being big enough. I dabbled with electronics right after getting out of the service, I'm 65 now so have forgotten most of that. About all I remember is I=E/R.

How much larger does the ground wire have to be to help improve the transmitted signal?

Sort of surprised your Triglide didn't come with a CB as ours did.

Thanks for your help, and ride safe.

Phu Cat. (Jim) If you'd prefer feel free to contact me on our e-mail at:tdhdnme@aol.com

 

[bulkness]

Phu Cat, I have a tech level Amateur Radio Operators License and I have forgotten how to use my own license. I am going to get back into the amateur radio. I have some left over 1/4 to 3/16 inch wide braided grounding strap that I will use to tie the metal plate in the tour box to the frame.

I thought the Tri-Glides did not come with the CB. Now I have read threads where folks had the PTT buttons installed.

Take care

 

[NamVet]

Being a old retired truck that has messed with CB's for the last 30 odd years, I took my swr meters and checked the long and shorty antenna on my 2014 Tri Glide. I found the readings to be very high to the point that damaged could or has occurred to the cb radio in the area of the finals. I check the grounds and found them all to be good, but never have seen the type of cb antenna connection used in the tour pack, all I can see is a single small wire going from the antenna to under the metal grounding plate. If anyone knows how this works or any info, I would like to see it. the power out put with stock antenna was very low to less than one watt, unless damage has occurred to the finals. Unable to get the stock antenna's swr down I purchase a two foot firestick with a adjustable tip and got the swr level down to under 1.5 over the entire band with the power output to 1.5 watts with modulation, still very low. The wife and I went for a ride, her on her Spyder with her CB and she said that I was now clearer and the distance was good to about one mile, but then fell off quickly, just a bit better that stock. I am looking for someone to check the output in watts for their stock CB to compare with mine, I am still concerned that damaged has occurred to my finals, however HD does not check power output or swr's and if the radio can transmit 20 feet to another bike then it is working.

So please post any results or send me a PM.

 

[dougv]

Bulkness I too am licensed, since 1968, man it doesn't feel like 46 years ago, but I was just a kid going into high school.....

Low band operation in a car/truck is difficult because the antenna systems are not very efficient or effective. I rode with a few Tri-Glides during the Northeast Rally and if I remember the CB antennas were only about 30" long at best so they are practically dummy loads, my Goldwing isn't much better, it may be slightly more.

NamVet, I wouldn't be too concerned about the power, SWR meters are not the most accurate either and any power indicated is probably way off. Remember too that CB is limited to 4 watts output maximum and you would need to measure with a dummy load to see what the actual power is. Even a 1.5:1 SWR will affect how the power meter measures the reflected power and power going to the antenna.

I worked for a Lafayette Radio store after college and we used to get the truckers stop by and they always complained about distance. Most had compromised antennas on the mirrors and were limited to a mile or two, but the antennas were a lot longer than what we have on our trikes so when you consider the length of the antenna and the lack of a good ground, if you get a mile out of it, your doing good. It's just the nature of the beast....

Being AM modulated doesn't help either, it takes a lot of audio power to be heard from longer distances too, thats why back in the CB heydays, power mics were the norm.

 

[tfdeputydawg]

Re: Wanting to improve my Ground Plane

Not licensed, not "radio" savy as some state.
However, I sold/installed CB's for many a year, back in the day. Also have tuned the SWR for many of my GW friends over the years.
USING THE OEM GW ANTENNA W/THE CENTER LOAD AND THE SWR TUNED TO THE LOWEST SETTING I COULD GET, I can talk easily 2 miles to a similar tuned GW. I have "talked" as much as 5 miles to cars and trucks.
I never heard of any truckers that could only talk a mile???? Co-phased antennas on trucks are the best one can do for a mobile.
Back in the day, I had a Pace 2300 CB w/a Turner +3 Power mic and co-phased Hustler antennas on the trunk of my 1970 Monte Carlo. On a "quiet" night, I "talked" with a fellow CB'r who got approx. 35 miles from me before we "lost" each other. Not many believed we were both legal at the time but, we were!!!!
Anybody remember talking "skip"?? Was sitting at a local drive-in one night Indiana, monitoring Channel 9. Got a distress call that turned out to be some one in Nevada!!!!
Called Indiana State Police with the guys location. They didn't want to believe me but forwarded a call to the locals in Nevada. Sure enough they found the guy, broke down, in the desert!!!!! The signal lasted about 5 minutes and was gone. Used to talk skip a lot off my base unit.

 

[Texan]

All this discussion about swr's and antenna lengths has got me to thinking. I'm planning to removed my tour-pak from my '13 and making my CB cable where I can disconnect it from out side the tour-pak with a cable coupler. Talked to the people at J&M about one of their hidden (inside the fairing) antennas. They indicate the range is somewhat the same as the regular outside antenna. (Which I find had to believe).

Back in my CB hay-days I use to set the SWR's but lengthening and shortening the stinger above the load on the antenna which you can't do with the Harley antennas. It was a big thing, burning out the finals in the radio, but don't hear much about it any more.

Good read: http://cbradiomagazine.com/April 2007/SWR.htm

Was going to take a serious look at the hidden CB antenna, but here again will only be using the CB when on long group rides, so would probably have the tour-pak back on.



8~\o

 

[vito]

Improving Ground Plane

As others have noted, CB's 27MHz frequencies need about a 9 foot antenna and 9 foot radials (ground plane) for optimum efficiency. That's not going to happen on a trike. The good news is that it is pretty easy to get an amateur radio license these days. No more morse. Then move to 2-meter. The antennae and ground plane needed to get the same efficiency as a 9 foot CB are 21 inches IIRC. Moreover most transceiver's are FM (peace and quiet). Best of all, hams have installed "repeaters" that retransmit your signal giving ranges over 50 miles. A club I rode with used 2m a decade ago. Food for thot ..

https://en.wikipedia.org/wiki/2-meter_band

 

[rhino 2]

Old post....But interesting never the less...The last time i used a CB Was in the early to mid 70's.. I had a Tram 23 channels i mounted the antennae dead center on the roof of my VW beetles.. It looked like a WWI German helmet... range wasn't a problem, And if i really needed extra range ,I would turn on the Heat...[80 watt linear]:cxtv::cxtv:

 

[rhino 2]

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