JT4x4

The Mud Pit => General => Topic started by: moosin on February 15, 2008, 10:16:42 PM

Title: new CB and antenna
Post by: moosin on February 15, 2008, 10:16:42 PM
jusy mounted my cb and antenna i got the firestik with adjustable tuner on top anyone got or know of anybody with the tool to properly tune the antenna. thanx.
Title: Re: new CB and antenna
Post by: HOT-ROD on February 15, 2008, 10:22:21 PM
if it is a fire stick, it should be tuned properly already. but how does it sound right now?
Title: Re: new CB and antenna
Post by: reg on February 16, 2008, 02:26:51 AM
if it is a fire stick, it should be tuned properly already. but how does it sound right now?

nope they need to be tuned.  mine does too.  :-\
Title: Re: new CB and antenna
Post by: Seabee_BUC on February 16, 2008, 02:32:06 AM
You need an RF/SRF (?) meter to tune your antenna. I think Radio Crack has them for cheap. Although, I'm not sure you can tune a firestik can you??? I know my Wilson 500 has a set screw to do this but i'm not sure of the Firestik... Just my .02
Title: Re: new CB and antenna
Post by: Axle on February 16, 2008, 02:39:00 AM
Ha!  I don't even know how to tune mine, because I have no idea what kind mine is!   ???


It works, even though I cracked the fiberglass.  Doesn't have much range though, and it didn't even before the crack.  I would be grateful for a lesson in antenna tuning from someone.  :-\ 
Title: Re: new CB and antenna
Post by: Seabee_BUC on February 16, 2008, 02:48:34 AM
I can do it, but I don't have the RF meter....
Title: Re: new CB and antenna
Post by: rocket on February 16, 2008, 02:57:45 AM
about $55 at radio shack
Title: Re: new CB and antenna
Post by: HOT-ROD on February 16, 2008, 05:22:25 AM
sucky. i just hooked mine up and bam i was a talking fool.
Title: Re: new CB and antenna
Post by: Doball on February 16, 2008, 05:29:25 AM
It's an SWR meter. Out of the package you should be ok for trails or 1-2 miles. Tuning will optimize your antenna for your radio to get max range and better quality reception. Before I spent $55 on a meter I'd go buy a cobra 129 or the radio shack equivalent for $120. It has the meter built in and allows for fine tuning the receive freq. Want to know how it is ask Cheeks when he gets back, he's got the uniden version.
Title: Re: new CB and antenna
Post by: HOT-ROD on February 16, 2008, 05:32:28 AM
ah you know what, i have the radio crack version, and that may be why i didnt have to tune mine. DUH!!!
Title: Re: new CB and antenna
Post by: reg on February 16, 2008, 08:00:32 PM
ah you know what, i have the radio crack version, and that may be why i didnt have to tune mine. DUH!!!


ok...  look.  the antenna has a screww at the top that wil lengthen or shorten the antenna.  the antenna needs to be tuned to 1.  what radio you have and 2.  how long a cable you are running.  the swr meter is a great tool that i wish i had.  te onboard ones are nice.
Title: Re: new CB and antenna
Post by: Erik on February 18, 2008, 04:15:40 PM
So far, everyone is close.

Radio doesn't matter.  Length of cable doesn't matter.  Whether the cable is coiled, rolled or in a mess, it doesn't matter.  Length of antenna doesn't matter.

What does matter?  A good ground for the radio.  A good ground for the antenna.  A good SWR.

SWR is Standing Wave Ratio.  It the ratio of power that being transmitted versus the amount that is being reflected back towards the radio from a bad impedance match.

Theoretically, a ratio of 1:1 is ideal, but is unachievable.  A SWR of 3:1 or less is what you are looking for.  This is what we tried to achieve on the boat when transmitting via HF at 1000 Watts.

An external SWR meter is needed.  The ones in the radio are ok, but not very reliable.
Title: Re: new CB and antenna
Post by: reg on February 18, 2008, 04:32:05 PM
copied and pasted  ;D

Quote
Setting the SWR
All CB antennas are tunable. Antennas that have an easy, often mechanical, tuning device are referred to as a "tunable antenna". Accordingly, lots of people think the other antennas are not tunable and so they make no attempt to have the antenna tuned. This is a critical mistake.

Wire-wound antennas without mechanical tuners, that test electrically long (higher SWR on ch 40), can be tuned by removing wire from the top. Remove the antenna cap, remove one wrap of wire and cut it off. Recheck the SWR again. As long as the SWR is higher on channel 40 continue to cut. Do not cut more than one wrap at a time. If SWR testing indicates the antenna is electrically short (higher SWR on ch 1), the coils at the top of the antenna can be separated and spaced further apart or accessories that increase the physical length of the antennas (springs, quick disconnects) can be added.

Solid fiberglass antennas (straight or helical wire impregnated in fiberglass resins) that are electrically too long (higher SWR on ch 40) can be cut shorter with a hacksaw or grinder. Cut only 1/4 of on inch at the most at one time. If the SWR test on one of these antennas indicates that it is electrically short (higher SWR on ch 1), the addition of a spring or quick disconnect (or both) is the only way to correct for the short condition.

Base loaded antennas with wire whips have a set screw (or two) just below the area that the whip is inserted into the loading coil. By loosening up the set screw(s) you are able to slide the whip up or down as required. If the SWR is higher on ch 40 slide the whip down, If the SWR is higher on ch 1 raise the whip.
Title: Re: new CB and antenna
Post by: HOT-ROD on February 18, 2008, 11:15:01 PM
ok way too much for me to understand.......

plug and play is my style.
Title: Re: new CB and antenna
Post by: moosin on February 19, 2008, 02:04:58 AM
ive got a firestik with tunable end and it works fine for now just wanted to make sure i was getting everything out of it that i could. i knew i neede a meter just wasnt sure if anybody already had one thanx.
Title: Re: new CB and antenna
Post by: Kral4me on February 19, 2008, 03:06:11 AM
*Blinks* wow.

Now I know why I just bat my eyelashes at Scott and say "baby my CB isn't working...can you fix it pluuueeeze?"

LOL  ;)
Title: Re: new CB and antenna
Post by: mallcrawl on February 19, 2008, 05:43:26 AM
comon now you was a wire rate that should be easy to understand

Title: Re: new CB and antenna
Post by: rocket on February 19, 2008, 12:20:47 PM
kool, anyone have a good meter?
Title: Re: new CB and antenna
Post by: mallcrawl on February 19, 2008, 01:42:31 PM
ayone wanna split up the cost of a meter for club use? I'll pitch $20 if someone who likes elctronics will help me tune mine .
Title: Re: new CB and antenna
Post by: HOT-ROD on February 19, 2008, 10:39:00 PM
kool, anyone have a good meter?

nope sorry
Title: Re: new CB and antenna
Post by: rocket on February 20, 2008, 02:35:44 AM
ayone wanna split up the cost of a meter for club use? I'll pitch $20 if someone who likes elctronics will help me tune mine .

I would if i had problems.  for trail rides and convoys, i think mine is ok.
Title: Re: new CB and antenna
Post by: HOT-ROD on February 20, 2008, 04:04:18 AM
ditto, new antenna is cheaper
Title: Re: new CB and antenna
Post by: Jeeper on February 20, 2008, 03:35:11 PM
I found this on EBAY for $19.99... It is an in-line tuner that goes between the antenna and the CB

Paradynamics PDC30 MATCHER SWR TUNER CB RADIO ANTENNAS
Item number: 140207651764

Hope this helps
Title: Re: new CB and antenna
Post by: mallcrawl on February 20, 2008, 04:50:23 PM
here is an even more in depth explanation for those intereseted
http://www.firestik.com/Tech_Docs/Setting_SWR.htm

tuning is easy enough just kinda time consuming but this is the cheapest meter I can find
http://www.radioshack.com/product/index.jsp?productId=2036239 and I'm not sure if I would trust it
Title: Re: new CB and antenna
Post by: HOT-ROD on February 20, 2008, 04:53:42 PM
cool
Title: Re: new CB and antenna
Post by: Erik on February 20, 2008, 05:09:56 PM
I found this on EBAY for $19.99... It is an in-line tuner that goes between the antenna and the CB

Paradynamics PDC30 MATCHER SWR TUNER CB RADIO ANTENNAS
Item number: 140207651764

Hope this helps

This really isn't what they are looking for.  It needs to be "permanently" installed.
Title: Re: new CB and antenna
Post by: mallcrawl on February 20, 2008, 05:11:18 PM
ohh and on jeep not having a decent roof to make a ground plane we will be lucky to see swr's under 3
Title: Re: new CB and antenna
Post by: HOT-ROD on February 20, 2008, 05:21:55 PM
i never thougt of that sort of thing.
Title: Re: new CB and antenna
Post by: HOT-ROD on February 20, 2008, 05:22:38 PM
i know, i know,

it's a jeep thing........
Title: Re: new CB and antenna
Post by: Erik on February 21, 2008, 05:49:53 PM
There are plenty of places on Jeeps that offer a good ground plane.  It may not be as omni-directional as possible, but there is plenty of metal to mount the antenna to.

Wranglers have the stopper for the spare tire on the right side, there is a company that makes a mount that goes in it.

Hood, bumpers, fenders.
Title: Re: new CB and antenna
Post by: Rebell Bull on February 22, 2008, 07:04:16 AM
Yep, mine is right on that stopper, but, I didn't buy a bracket, I just made one, easy cheasy.