HarleyTechTalk

Technical Forums => Audio and Electronics => Topic started by: Jaxryde on July 29, 2018, 11:35:48 AM

Title: Replace whip antennas
Post by: Jaxryde on July 29, 2018, 11:35:48 AM
Looking to replace my two long whip antennas for short runner ones. 2001 Ultra Classic with CB. Looking for direct replacement recommendations
Title: Re: Replace whip antennas
Post by: Ohio HD on July 29, 2018, 12:16:19 PM
Look on the HD site, they sell the short antennas.
Title: Re: Replace whip antennas
Post by: calbyker69 on July 29, 2018, 02:05:15 PM
I have the two shorties from Kuryaken. Work just fine.
Title: Re: Replace whip antennas
Post by: FurryOne on August 03, 2018, 07:37:25 AM
Ether way you go, once you install the CB antenna it's best to check the tuning since I've seen factory antennas way out of tune.  Also, going to a shorter antenna generally decreases your range due to the decrease in wavelength.  If you have a friend that's into Ham radio they might check the SWR for you (Those cheap $20 meters are no good).  You'd be looking to get as close to 1.1:1 SWR as you can get - 1.3:1 or lower is good.  The regular length (3') antenna I got from H-D was like 3:1 SWR with no real way to adjust it - look for an antenna that offers easy adjustment of the "loading".  Also, as you go smaller, it's harder to reach a low SWR.  Here's a picture of a small magnetic mount antenna being tuned - I could never get it any better than about 1.6:1 due to it's characteristics.
Title: Re: Replace whip antennas
Post by: Paniolo on August 03, 2018, 07:55:05 AM
Quote from: FurryOne on August 03, 2018, 07:37:25 AM
Ether way you go, once you install the CB antenna it's best to check the tuning since I've seen factory antennas way out of tune.  Also, going to a shorter antenna generally decreases your range due to the decrease in wavelength.  If you have a friend that's into Ham radio they might check the SWR for you (Those cheap $20 meters are no good).  You'd be looking to get as close to 1.1:1 SWR as you can get - 1.3:1 or lower is good.  The regular length (3') antenna I got from H-D was like 3:1 SWR with no real way to adjust it - look for an antenna that offers easy adjustment of the "loading".  Also, as you go smaller, it's harder to reach a low SWR.  Here's a picture of a small magnetic mount antenna being tuned - I could never get it any better than about 1.6:1 due to it's characteristics.

So where does one go to have their CB radio properly attenuated?
Title: Re: Replace whip antennas
Post by: FurryOne on August 03, 2018, 08:28:40 PM
Quote from: Paniolo on August 03, 2018, 07:55:05 AM

So where does one go to have their CB radio properly attenuated?

Ask around - most areas have Ham Radio clubs, and there are still a lot of people who have CB radios.  Maybe look for a store that sells radio equipment?  Google ham radio clubs?  or even radio repair shops?  The RigExpert AA-30 I have goes for about $220, which is why it's best to find a radio guy who will help you.  I'd help if you were local, but I don't think that's the case.
Title: Re: Replace whip antennas
Post by: FSG on August 04, 2018, 02:37:42 AM
Quoteattenuated

:scratch:
Title: Re: Replace whip antennas
Post by: Paniolo on August 04, 2018, 08:40:11 AM
Quote from: FSG on August 04, 2018, 02:37:42 AM
Quoteattenuated

:scratch:

It's a term I learned from the guys in the radio shop who did all the two-way radio installs on our cars and motorcycles. I took it to mean that the radio and antenna were properly tuned and putting out a 5x5 signal in amplitude and modulation.

Title: Re: Replace whip antennas
Post by: Coyote on August 04, 2018, 08:46:33 AM
You need to find better teachers then.  :crook:

QuoteSo where does one go to have their CB radio antenna properly tuned attenuated?
Title: Re: Replace whip antennas
Post by: Rockout Rocker Products on August 04, 2018, 02:27:22 PM
Some good reading here.... https://books.google.com/books?id=wUzQN8GN_zYC&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false (https://books.google.com/books?id=wUzQN8GN_zYC&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false)

This was the Bible back in the day, and dispels some common myths.  :up:
Title: Re: Replace whip antennas
Post by: chaos901 on August 08, 2018, 06:47:58 AM
The short whips from H-D are specific to either the CB or Radio, some of the others (like J&M) can be interchanged.  I have used both over the years and have not noticed any measurable difference.
Title: Re: Replace whip antennas
Post by: FurryOne on August 08, 2018, 08:47:36 AM
Quote from: chaos901 on August 08, 2018, 06:47:58 AM
The short whips from H-D are specific to either the CB or Radio, some of the others (like J&M) can be interchanged.  I have used both over the years and have not noticed any measurable difference.

Most likely because AM/FM radios can be run using a coat hanger for an antenna - don't try that with a CB.  I don't have a tour pack, but from what I've seen it looks to me like they put the loading coil for the CB inside the corner of the Tour Pack, which would mean they are base-loading the CB antenna, so unless the pictures in the GMA18 catalog are doctored, they use the same shorty mast for both the AM/FM and the CB, and make up for it with their loading scheme for the CB side. (Truth be told - top-loading is the best, followed by center-loading, with base-loading last.)  The Firestik2 I have on my SGS is a top-loaded, No Ground Plane (NGP) type.