Please login or register.

Login with username, password and session length
Advanced search  
Pages: [1] 2  All

Author Topic: Any difference between AM/FM and CB antennae?  (Read 10324 times)

0 Members and 1 Guest are viewing this topic.

1abastarsmda

  • 2.5K CVO Member
  • **
  • Offline Offline
  • Posts: 3403
    • PA

    • CVO1: 2021 CVO Limited
Any difference between AM/FM and CB antennae?
« on: November 26, 2008, 10:20:43 PM »

I noticed that Harley has separate part numbers for the shorty AM/FM antenna and the CB antenna, although they look identical.  Is there a difference?  I have noticed that in looking at aftermarket antennae, they usually just mention the AM/FM.  I already got the Harley shorties, but I saw chrome shorties available and I thought that might me a nice touch, but they only list AM/FM.
Logged

RedDevil

  • 5k CVO Member
  • ***
  • Offline Offline
  • Posts: 6170
  • EBCM #747.2 It's all good

    • CVO1: '11 FLTRUSE Gray Ghost
    • CVO2: '12 FLHXSE3 Hot Citrus/Antique Gunstock
Re: Any difference between AM/FM and CB antennae?
« Reply #1 on: November 26, 2008, 10:25:46 PM »

I noticed that Harley has separate part numbers for the shorty AM/FM antenna and the CB antenna, although they look identical.  Is there a difference?  I have noticed that in looking at aftermarket antennae, they usually just mention the AM/FM.  I already got the Harley shorties, but I saw chrome shorties available and I thought that might me a nice touch, but they only list AM/FM.

the only thing I can think of without actually looking at the antennas is that they may have either put a base load on the CB antenna or the wire wrapping is different (read more) on the CB antenna over the AM/FM antenna.  I actually like the idea, if there truly is a difference, of having a designed dedicated CB antenna over a mult-purpose antenna.  Be interesting to see what the SWR out of the bag is on the HD CB antenna.

   :devil:
Logged

2012 FLHXSE3
Hot Citrus/Antique Gunstock

hard10

  • Emperor of the Imperial Grand Masters of Sarcasm
  • 5k CVO Member
  • ***
  • Offline Offline
  • Posts: 7525
  • EBCM # 6 1/157.48

    • CVO1: FLHTCUSE²
Re: Any difference between AM/FM and CB antennae?
« Reply #2 on: November 26, 2008, 10:32:43 PM »

Yes. The CB will have a coil in it somewhere. I have not looked at the new shorty's close enough but can go outside if you'd like.
AJ

Bubba

  • 1K CVO Member
  • *
  • Offline Offline
  • Posts: 2486
  • LIVE TO RIDE! RIDE TO EAT!

    • CVO1: 2006 CUSE B/S
Re: Any difference between AM/FM and CB antennae?
« Reply #3 on: November 26, 2008, 11:06:36 PM »

Yes AJ is right the CB antenna needs to be in length 102" where I think the length for the am/fm is 42" (May be off on this one)
If you look at some of the shorties antennas close enough you will see the wire wrap around the antenna shaft and if you was to stretch it out it should measure the 102" need for the CB band.





Wave length calculator        http://www.qsl.net/kd4sai/antencal.html


« Last Edit: November 27, 2008, 09:04:18 AM by bubba »
Logged
Any-day above ground is worth living so let's go riding!!!

LarryB

  • Tennessee Squire
  • 2.5K CVO Member
  • **
  • Offline Offline
  • Posts: 3656

    • CVO1: 09 FLTRSE3 The Grey Ghost
Re: Any difference between AM/FM and CB antennae?
« Reply #4 on: November 27, 2008, 07:32:57 AM »

yes there is a difference, but not as stated.
The H-D antennas s...........inhale.
J&M makes a dual use antenna that fits perfectly and looks exactly the same
CB/AM/FM/WB. comes pre-tune to a H-K advanced system. no WFR adjusting need. plug and play.
30 bucks Sierra electronics, 2 day shipping
now it says -08 but works fine on the 09, but you need an antenna splitter also from Sierra
Logged
Take it Easy Greasy Cuz it's a long walk home.

Did I shave my head for this?

1abastarsmda

  • 2.5K CVO Member
  • **
  • Offline Offline
  • Posts: 3403
    • PA

    • CVO1: 2021 CVO Limited
Re: Any difference between AM/FM and CB antennae?
« Reply #5 on: November 27, 2008, 07:35:37 AM »

But what I would like would be 2 chrome shorties.  I saw that Kuryakyn makes them, but again, only stating AM/FM.  I guess I'll do without until I see them somewhere.
Logged

Bubba

  • 1K CVO Member
  • *
  • Offline Offline
  • Posts: 2486
  • LIVE TO RIDE! RIDE TO EAT!

    • CVO1: 2006 CUSE B/S
Re: Any difference between AM/FM and CB antennae?
« Reply #6 on: November 27, 2008, 08:54:14 AM »

yes there is a difference, but not as stated.
The H-D antennas s...........inhale.
J&M makes a dual use antenna that fits perfectly and looks exactly the same
CB/AM/FM/WB. comes pre-tune to a H-K advanced system. no WFR adjusting need. plug and play.
30 bucks Sierra electronics, 2 day shipping
now it says -08 but works fine on the 09, but you need an antenna splitter also from Sierra


I have the J&M antennas like the looks but hate the performance.  Took them back off and put them in the cabinet.  I figured I lost about 10 to 15% over the stock whips.  JMHO.
 
Would I buy them again,,,   for looks  YES    for functionality   NO.     I have 2 of these for sale if anyone would like them $35.ºº for the pair + shipping.

Logged
Any-day above ground is worth living so let's go riding!!!

RedDevil

  • 5k CVO Member
  • ***
  • Offline Offline
  • Posts: 6170
  • EBCM #747.2 It's all good

    • CVO1: '11 FLTRUSE Gray Ghost
    • CVO2: '12 FLHXSE3 Hot Citrus/Antique Gunstock
Re: Any difference between AM/FM and CB antennae?
« Reply #7 on: November 27, 2008, 09:13:11 AM »

I have the J&M antennas like the looks but hate the performance.  Took them back off and put them in the cabinet.  I figured I lost about 10 to 15% over the stock whips.  JMHO.
 
Would I buy them again,,,   for looks  YES    for functionality   NO.     I have 2 of these for sale if anyone would like them $35.ºº for the pair + shipping.



I have the J&M shorties and don't have any problems with them.  But I live in a more RF-dense environment also.  So that could be a big reason why I saw no performance loss on the FM side.  On the CB side I found a noticeable gain in performance.  However, for me it's primarily looks, because unless I'm in a group ride, I don't use the CB, and I listen to XM exclusively, never use the FM radio.  I do use the Weather radio every once in a while though. 

   :devil:
Logged

2012 FLHXSE3
Hot Citrus/Antique Gunstock

RedDevil

  • 5k CVO Member
  • ***
  • Offline Offline
  • Posts: 6170
  • EBCM #747.2 It's all good

    • CVO1: '11 FLTRUSE Gray Ghost
    • CVO2: '12 FLHXSE3 Hot Citrus/Antique Gunstock
Re: Any difference between AM/FM and CB antennae?
« Reply #8 on: November 27, 2008, 09:50:24 AM »

yes there is a difference, but not as stated.
The H-D antennas s...........inhale.
J&M makes a dual use antenna that fits perfectly and looks exactly the same
CB/AM/FM/WB. comes pre-tune to a H-K advanced system. no WFR adjusting need. plug and play.
30 bucks Sierra electronics, 2 day shipping
now it says -08 but works fine on the 09, but you need an antenna splitter also from Sierra


Actually yes, the difference is as stated.  The CB antennas physical or electrical length of the antenna must be in proportion to the frequency the radio is transmitting on.  As such, the CB antenna is tuned for 27 MHz.  300/27=11.11 meters or roughly 36 feet.  Typically antennas are cut to 1/4 wave configurations, so if you take the 36 ft for a full wave and divide by 4 you get 9 feet.  So a typical 1/4 wave CB antenna is 9 ft or 108 inches in length.  You can electrically achieve this, by using an antenna tuner/coupler (which is used for multi-band radios on a single length antenna, typically mid-band for a multi-band radio), or physically, by either the actually length of 1/4 wave's worth of "copper" wrapped around a "stick" or a phsically correct size, (like a 9 ft whip antenna), or using a combination of straight wire and loading coils.  You've seen the CB antennas with loading coils, especially on semis.  They either will have a "bulge" about half way up (center loaded) the whip or stick, or at the base of the antenna, base load.  Harley does a combination with a base load, except it's physically located in the tour pak.  That's how you can tell which antenna (the right one by the way, looking from the rear of your bike) is the CB antenna.  Using the loading coil method is how Harley's older antennas were the same, and why J&M's and others are the same.  Unless HD has removed the loading coil out of the tourpak on the 09's, I'm not sure why they are separate part numbers.   :nixweiss:

   :devil:
Logged

2012 FLHXSE3
Hot Citrus/Antique Gunstock

ultrafxr

  • There are no sure answers, only better questions. - Dick Van Dyke
  • 5k CVO Member
  • ***
  • Offline Offline
  • Posts: 5466
  • No problem is so small it cannot be misunderstood.
    • TN


    • CVO1: 2020 FLHTCUTG Tahitian Teal
    • CVO2: 2017 FLHTKSE Palladium Silver/Phantom Blue/Wicked Sapphire-traded
    • CVO3: 2012 FLHTCUSE7 Electric Orange/Black Diamond-traded
Re: Any difference between AM/FM and CB antennae?
« Reply #9 on: November 27, 2008, 10:24:35 AM »

I have the J&M shorties and don't have any problems with them.  But I live in a more RF-dense environment also.  So that could be a big reason why I saw no performance loss on the FM side.  On the CB side I found a noticeable gain in performance.  However, for me it's primarily looks, because unless I'm in a group ride, I don't use the CB, and I listen to XM exclusively, never use the FM radio.  I do use the Weather radio every once in a while though. 
   :devil:
If I'm riding with anyone else I always use my CB and have found the J&M shorties to work just fine.  But I have noticed a significant reduction in sensitivity of the FM radio.  But like you RedDevil, I listen to XM exclusively or maybe sometimes a CD so that is not really an issue. 
Logged



Places ridden on my bike from my driveway.
IBA member # 45520

JDOFLHRIDER

  • Vendor
  • 1K CVO Member
  • *
  • Offline Offline
  • Posts: 1125
  • 2010 FLHTCUSE5 BURNT AMBER -HOT CITRUS
Re: Any difference between AM/FM and CB antennae?
« Reply #10 on: November 27, 2008, 12:56:57 PM »

If you would like to use to harleys new antenas there is a differance at bottom of the antena one has cb cast in plastic ,am/fm has no marking on the 09 antenas.RIDE SAFE JDO
Logged

RedDevil

  • 5k CVO Member
  • ***
  • Offline Offline
  • Posts: 6170
  • EBCM #747.2 It's all good

    • CVO1: '11 FLTRUSE Gray Ghost
    • CVO2: '12 FLHXSE3 Hot Citrus/Antique Gunstock
Re: Any difference between AM/FM and CB antennae?
« Reply #11 on: November 27, 2008, 03:30:18 PM »

If you would like to use to harleys new antenas there is a differance at bottom of the antena one has cb cast in plastic ,am/fm has no marking on the 09 antenas.RIDE SAFE JDO

Does anyone that has an 09 SEUC know if the loading coil is still in the tourpak?  :nixweiss: 

   :devil:
Logged

2012 FLHXSE3
Hot Citrus/Antique Gunstock

hard10

  • Emperor of the Imperial Grand Masters of Sarcasm
  • 5k CVO Member
  • ***
  • Offline Offline
  • Posts: 7525
  • EBCM # 6 1/157.48

    • CVO1: FLHTCUSE²
Re: Any difference between AM/FM and CB antennae?
« Reply #12 on: November 27, 2008, 03:47:32 PM »

Actually yes, the difference is as stated.  The CB antennas physical or electrical length of the antenna must be in proportion to the frequency the radio is transmitting on.  As such, the CB antenna is tuned for 27 MHz.  300/27=11.11 meters or roughly 36 feet.  Typically antennas are cut to 1/4 wave configurations, so if you take the 36 ft for a full wave and divide by 4 you get 9 feet.  So a typical 1/4 wave CB antenna is 9 ft or 108 inches in length.  You can electrically achieve this, by using an antenna tuner/coupler (which is used for multi-band radios on a single length antenna, typically mid-band for a multi-band radio), or physically, by either the actually length of 1/4 wave's worth of "copper" wrapped around a "stick" or a phsically correct size, (like a 9 ft whip antenna), or using a combination of straight wire and loading coils.  You've seen the CB antennas with loading coils, especially on semis.  They either will have a "bulge" about half way up (center loaded) the whip or stick, or at the base of the antenna, base load.  Harley does a combination with a base load, except it's physically located in the tour pak.  That's how you can tell which antenna (the right one by the way, looking from the rear of your bike) is the CB antenna.  Using the loading coil method is how Harley's older antennas were the same, and why J&M's and others are the same.  Unless HD has removed the loading coil out of the tourpak on the 09's, I'm not sure why they are separate part numbers.   :nixweiss:

   :devil:

Isn't that what I said?   ( ;D)

RedDevil

  • 5k CVO Member
  • ***
  • Offline Offline
  • Posts: 6170
  • EBCM #747.2 It's all good

    • CVO1: '11 FLTRUSE Gray Ghost
    • CVO2: '12 FLHXSE3 Hot Citrus/Antique Gunstock
Re: Any difference between AM/FM and CB antennae?
« Reply #13 on: November 27, 2008, 03:57:33 PM »

Isn't that what I said?   ( ;D)

yep, you sure did, just reinforcing what ya said AJ.  Larry B stated that the differences weren't as stated, and I just reinforced what you said that it was....I think... :confused5: :huepfenjump3:

   :devil:
Logged

2012 FLHXSE3
Hot Citrus/Antique Gunstock

1abastarsmda

  • 2.5K CVO Member
  • **
  • Offline Offline
  • Posts: 3403
    • PA

    • CVO1: 2021 CVO Limited
Re: Any difference between AM/FM and CB antennae?
« Reply #14 on: November 27, 2008, 07:38:21 PM »

So, to summarize, it looks like the answer to the original question is yes.  They are different. :apple:
Logged
Pages: [1] 2  All
 

Page created in 0.207 seconds with 25 queries.