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[hogheritage04]

Red,

 As with many here on the forum, I am VERY interested in your report on the performance of these J&M antennas.  I have bought from J&M before, and have nothing but good to say about them, their customer service and their quality.  We use the CBs alot when on group rides for our Road Captains Lead and Sweep, so I don't want my CB to be degraded.  My understanding of how the CB works is "Line-of-Sight".  So if this is true, it would seem that the taller the antenna, the longer the reception.  Let us know, once you get the antennas on if not only the power is the same, but also the distance.  Sure appreciate all the feedback as it saves the rest of us from experimenting.  Can't wait to see the pics and your performance report.  Happy New Year and thanks. [smiley=xyxthumbs.gif]

[RedDevil]

Red,

 As with many here on the forum, I am VERY interested in your report on the performance of these J&M antennas.  I have bought from J&M before, and have nothing but good to say about them, their customer service and their quality.  We use the CBs alot when on group rides for our Road Captains Lead and Sweep, so I don't want my CB to be degraded.  [highlight]My understanding of how the CB works is "Line-of-Sight".[/highlight]  So if this is true, it would seem that the taller the antenna, the longer the reception.  Let us know, once you get the antennas on if not only the power is the same, but also the distance.  Sure appreciate all the feedback as it saves the rest of us from experimenting.  Can't wait to see the pics and your performance report.  Happy New Year and thanks. [smiley=xyxthumbs.gif]

Latest update, the Jester is down until I get back from Arizona on the 15th.  They had to order a part (fairing seal) that won't be in for about 5 days.  By that time I'll be out of town ... so they are going to keep the bike until I get back.  I promise I'll put out a report on the antennas...sorry for the wait.  

CB radios operate at 27MHz, which is the high end of the HF band.  You're somewhat correct about CB's being line of site, but not because of the propagation characteristics of HF.  HF is a great "long-haul" frequency band.  In fact, it's not uncommon to skip (talk) many hundreds of miles with a CB radio.  You're limited to distance because of power.  By FCC rules, maximum power for a CB is 4 Watts, and the more detuned your antenna is the lower your Effective Radiated Power (ERP) is.  Many things play into lower or higher ERP.  The amount of line loss, connectors, and yes, length of antenna.  The closer you can get to a true quarter-wave antenna, the better.  However, a straight quarter-wave antenna for 27 MHz is 18 ft long.  Totally impractical for any mobile unit.  So antenna manufacturers, make shorter antennas that fool the radio into thinking it is a quarter-wave antenna, buy doing copper wrapping, (such as the J&M shorties), loading coils, or electronically fooling the radio with an antenna coupler.   If you have a perfect 1:1 SWR and an antenna with 0db gain, you're probably still going to have a signal loss of about 2-3 db because of the connector on the back of the radio, coax length, and the connector at the antenna, so your ERP would actually be lower than the rated 4 watts.  Sorry to ramble on about this...I've been a comm guy for a long time...and I get a little carried away sometime... [smiley=soapbox.gif]
Red

[RJ749]

Latest update, the Jester is down until I get back from Arizona on the 15th.  They had to order a part (fairing seal) that won't be in for about 5 days.  By that time I'll be out of town ... so they are going to keep the bike until I get back.  I promise I'll put out a report on the antennas...sorry for the wait.  

CB radios operate at 27MHz, which is the high end of the HF band.  You're somewhat correct about CB's being line of site, but not because of the propagation characteristics of HF.  HF is a great "long-haul" frequency band.  In fact, it's not uncommon to skip (talk) many hundreds of miles with a CB radio.  You're limited to distance because of power.  By FCC rules, maximum power for a CB is 4 Watts, and the more detuned your antenna is the lower your Effective Radiated Power (ERP) is.  Many things play into lower or higher ERP.  The amount of line loss, connectors, and yes, length of antenna.  The closer you can get to a true quarter-wave antenna, the better.  However, a straight quarter-wave antenna for 27 MHz is 18 ft long.  Totally impractical for any mobile unit.  So antenna manufacturers, make shorter antennas that fool the radio into thinking it is a quarter-wave antenna, buy doing copper wrapping, (such as the J&M shorties), loading coils, or electronically fooling the radio with an antenna coupler.   If you have a perfect 1:1 SWR and an antenna with 0db gain, you're probably still going to have a signal loss of about 2-3 db because of the connector on the back of the radio, coax length, and the connector at the antenna, so your ERP would actually be lower than the rated 4 watts.  Sorry to ramble on about this...I've been a comm guy for a long time...and I get a little carried away sometime... [smiley=soapbox.gif]
Red

It's great to hear what/how this works, I have heard a million explanations over the years from the guy that stayed at the Holiday Inn Express lsst night.

We'll hang on until you get it back.  Hope it is as good as their other stuff.

[RedDevil]

It's great to hear what/how this works, I have heard a million explanations over the years from the guy that stayed at the Holiday Inn Express lsst night.

We'll hang on until you get it back.  Hope it is as good as their other stuff.

Thanks for the patience.    Like I stated earlier, they appear to be of excellent quality.  I've had previous experience with J&M products and have always been totally pleased with them.  I didn't hesitate to buy them when I saw that they were now offering shorty antennas.  If they work like their other products they will work as advertised, or as their designer told me they will work.  I'll be really surprised if they don't.
Red

[bisounours]

I'll wait your report, it's not a problem.
We'll hang till you get it back.

And J&M will wait later for my order.
They are nice guys and excellent contact with John.

Regards
Jacques

[hogheritage04]

Red,

 Thanks for the detailed explanation.  I found it very educational, and explained a lot about why/how the CB really works.  So, when you get back we will all be waiting to hear your report.  Please post some pics with the new antennas so we can see what they look like on the bike.  Until you report back....

[magicl1]

Sorry to ramble on about this...I've been a comm guy for a long time...and I get a little carried away sometime... [smiley=soapbox.gif] [smiley=welcome_005.gif]
Red

I would not worry about the Soap Box!  Good stuff!  It's always interesting to read about how this works!

Since you have a good understanding, do you have any suggestions for a portable CB unit?  The wife and I head up to the White Mountains for the weekend here in AZ (she takes the car with the 2 dogs and our cat) and I have the dirty job of riding the Motor Cycle up ( [smiley=huepfenjump3.gif] ).  It would be nice to comunicate between vehicles, but I do not want anything that is hard wired or permanent.

[RedDevil]

I would not worry about the Soap Box!  Good stuff!  It's always interesting to read about how this works!

Since you have a good understanding, do you have any suggestions for a portable CB unit?  The wife and I head up to the White Mountains for the weekend here in AZ (she takes the car with the 2 dogs and our cat) and I have the dirty job of riding the Motor Cycle up ( [smiley=huepfenjump3.gif] ).  It would be nice to comunicate between vehicles, [highlight]but I do not want anything that is hard wired or permanent[/highlight].

Cobra still makes, I believe, and GE used to make, a really nice, what they called Emergency CB unit.  Which sounds like exactly what you're looking for.  The whole unit with magnetic telescoping antenna, came in a nice plastic case and you could just throw the unit in the trunk or under the seat, when you weren't using it.  To use it all you have to do is plug the radio into the cigarette lighter and put the mag mount antenna on the roof and start transmitting...great little portable rig.  Here's a link for a GE unit:  http://auctions.yahoo.com/i:cb%20portable%20GE%20CB%2040%20channel%20radio%20model%203-5920:93081381  There are still plenty of CBs out there.  If you want a hand-held walkie-talkie type, just do a Google search on portable CB radios or hand held CB radios and you'll get a bunch of hits....hope this helps.
Red

[RedDevil]

As promised, here's some pics of the J&M shorty antenna mounted on my Jester.  The antenna connector in the tour pack is of a funky design that I've never seen before for a CB...so I have to see if I can get parts to make a cable to run between my meter and the antenna connector.  I don't feel like taking off the fairing to see if the connector on the radio is the same as the tour pak or a standard PL-259 connector that most CBs have.  I put the antennas on the bike and tried them out...the reception is definitely better, than the factory antennas.  I could barely pick up the truckers off of I-95 (about two miles from my house) with the factory antennas and the bike sitting in the garage.  They were "booming" in after putting the J&M's on.  I did a radio check with one of the truckers and he stated that I sounded great and was coming in "loud and clear".  Never got that from a trucker before on my HD CB's with the stock whips.  So I'm getting out at least 2 miles.  I noticed, that the "noise floor" was higher with these antennas, then with the stock antennas, which resulted in having to raise the squelch a bar or two. That signifies that they are pulling the signal better than the stock one.   Granted this is all very non-technical way of testing the antennas, but without the proper connectors, I can't put the meter in line to do a calibration.  Bottom line, I think that even without taking any measurements, they are better than stock.  They are semi-rigid, so they won't have that bent appearance like the rubber duckies do after riding for awhile, but yet are flexible enough that if you bump into them, they won't snap.  They appear to be well made, and they mount right on to the stock mount with no adapters and then are secured with an allen set screw, just like the factory antennas.   Very nice setup...I'm glad I got them.
Cheers  [smiley=xyxthumbs.gif],
Red  

[RedDevil]

another of the antennas from the side.

[bisounours]

Thanks for your report, RedDevil ! [smiley=xyxthumbs.gif]
You confirm the first impression.
Now, I'll send my order.

Thanks for your tests and your help.

Regards
Jacques

[RJ749]

Yep, thanks for the report, I hope you can get your meter on them in the future and let us know what you think.

[ESJ JESTER]

It is not a standard PL-259 on the radio either.....

[RJ749]

It is not a standard PL-259 on the radio either.....

Dang...........

[RedDevil]

It is not a standard PL-259 on the radio either.....

Wonderful  , that's what I was afraid of.  I wonder why they went with that odd-ball connector? [smiley=nixweiss.gif] Just another way that the MoCo marches to their own drummer.  :-/ Would have made life a lot easier if they had gone with industry standard connectors.
Cheers [smiley=xyxthumbs.gif],
Red