Forum Index
Jeep Horizons HomeLinksJeep Horizons Tech Write-upsJeep newsLand useContact

 Watched TopicsWatched Topics   FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

Antenna questions

Goto page Previous  1, 2, 3
 
Post new topic   Reply to topic     Forum Index -> Electronic
View previous topic :: View next topic  
Author Message
IBTJn
Moderator
Moderator


Joined: 31 Dec 2004
Location: Just Outside of Portland, OR

PostPosted: Thu Sep 29, 2005 4:53 pm    Post subject: Reply with quote

1fox2go wrote:
k ill pick one up 50 bucks is a lot of money for my cb seeing as how i dont use it all the time thanks

If I may recommend, it might be wise to make sure the noise (RFI) is being generated by the electrical system first. It only takes a few minutes and costs nothing. Disconnect the coax from the back of the radio (don't key the mic at all) and drive around a little listen and see if you get the same noise/static you were hearing. If you do, than it is in fact the input power needing help. If not, than it's likely coming in through the antenna system someplace.

If it's power input noise (or not) however, you might consider wiring the CB power input like THIS WRITE UP using the "Option A." It should take the majority of any electrical noise out of the power input. I've never needed filtration after wiring my radios this way. Save the $50 and try this first...especially if $50 is hard to come by. Option "A" will cost you a few dollars instead and some extra time...but well worth it IMO.

Just a cheaper alternative to consider and maybe try before you spend $$.

Wink
Back to top
View user's profile Send private message
1fox2go
Member


Joined: 01 Dec 2004
Location: Fishersville, Virginia

PostPosted: Thu Sep 29, 2005 7:41 pm    Post subject: Reply with quote

i have it wired to the battery however i used the wire that came with the cb and put red on postive post on bat and black on neg


should i add or take anything away to make it better?
_________________
96 Cherokee 7.5 inch TnT long arm Locked F/R, D44 rear, 4.56s, 35x12.50 Muds/36x12.50 TSLs
Back to top
View user's profile Send private message Send e-mail AIM Address
ThePhantum
Pissed-Off Admin
Pissed-Off Admin


Joined: 23 Jan 2004
Location: I knew it...I'm surrounded by Assholes!

PostPosted: Thu Sep 29, 2005 9:41 pm    Post subject: Reply with quote

Read the writeup. It pretty much shows you exactly what to do.
_________________

97 XJ Sport with a bunch of stuff
Quote:
Never argue with idiots, they drag you down to their level and beat you with experience
Back to top
View user's profile Send private message AIM Address Yahoo Messenger MSN Messenger
1fox2go
Member


Joined: 01 Dec 2004
Location: Fishersville, Virginia

PostPosted: Sat Oct 01, 2005 5:29 pm    Post subject: Reply with quote

i have a new cb its a cobra DX III and its a little better than my old radio shack

when i turn it on i get this really low "hum" doesnt matter what volume the cb is at it can be just barely turned on and you hear it

any idea what it could be?
_________________
96 Cherokee 7.5 inch TnT long arm Locked F/R, D44 rear, 4.56s, 35x12.50 Muds/36x12.50 TSLs
Back to top
View user's profile Send private message Send e-mail AIM Address
1fox2go
Member


Joined: 01 Dec 2004
Location: Fishersville, Virginia

PostPosted: Sat Oct 01, 2005 6:34 pm    Post subject: Reply with quote

engine isnt running doors are not open
_________________
96 Cherokee 7.5 inch TnT long arm Locked F/R, D44 rear, 4.56s, 35x12.50 Muds/36x12.50 TSLs
Back to top
View user's profile Send private message Send e-mail AIM Address
IBTJn
Moderator
Moderator


Joined: 31 Dec 2004
Location: Just Outside of Portland, OR

PostPosted: Sat Oct 01, 2005 9:27 pm    Post subject: Reply with quote

Disconnect the coax from the back of the radio and see if the noise is still there.
-If not, then it's coming in through the antenna.
-If it is, then I'd ask if the ACC part of the ignition is on?
--If not, then I don't have a clue. It could be several things...but let us know what the above does first.

Process of elimination is the only way I know to isolate these kinds of things.

Wink
Back to top
View user's profile Send private message
1fox2go
Member


Joined: 01 Dec 2004
Location: Fishersville, Virginia

PostPosted: Mon Oct 03, 2005 8:33 am    Post subject: Reply with quote

disconnected the coax and hum is still there...keys arent even in the ignition
_________________
96 Cherokee 7.5 inch TnT long arm Locked F/R, D44 rear, 4.56s, 35x12.50 Muds/36x12.50 TSLs
Back to top
View user's profile Send private message Send e-mail AIM Address
IBTJn
Moderator
Moderator


Joined: 31 Dec 2004
Location: Just Outside of Portland, OR

PostPosted: Mon Oct 03, 2005 2:07 pm    Post subject: Reply with quote

1fox2go wrote:
disconnected the coax and hum is still there...keys arent even in the ignition

Bum deal. So this cobra 19DX you have is brand new out of the box? ??? (if not, let us know and we can go from there)

If it's brand new, I'd go ahead and still wire it with RG mini 8 coax. Then (without hesitation) I'd run a 14 gauge ground strap from the chassis of the radio to a good tub ground someplace inside, like by the fuse box behind the glove box where it's easy to get to. If the noise is still there, take the radio back where you got it and exchange it. I'd leave all the wiring there for the replacement radio though. I typically use quick disconnects on the power supply wires, too...for just such an occasion.
Something smells funny on this though. I don't ever recall RFI like you are hearing without the engine/ACC ON, and/or coax connected. And rarely are new radios bad right out of the box (but it does happen).

Man...talk about snake bit. Rolling Eyes
Back to top
View user's profile Send private message
1fox2go
Member


Joined: 01 Dec 2004
Location: Fishersville, Virginia

PostPosted: Mon Oct 03, 2005 6:23 pm    Post subject: Reply with quote

no it aint new Sad bought it off a guy hard for cash 40 bucks with the cobra magnet antenna sorry its new to me didnt mean to mislead

i will be working on the power wire this weekend

what puzzles me was before i tuned the antenna with the swr i could talk to someone over a good distance with lots of objects good distance being 5 miles ish

now that i tuned it i dont get that far...however i did talk to a guy one day who was about 10 miles away and i didnt have the squelch up...he was a little static but i could easily tell what he was saying but i havent gotten that...stevo thinks i may have swrd it wrong

as for the noise when the engine is running and your driving you cant here it but if i stop and listen its there...not a big deal but just one of those things that would be nice to fix ya know?

thanks for helpin me out
_________________
96 Cherokee 7.5 inch TnT long arm Locked F/R, D44 rear, 4.56s, 35x12.50 Muds/36x12.50 TSLs
Back to top
View user's profile Send private message Send e-mail AIM Address
IBTJn
Moderator
Moderator


Joined: 31 Dec 2004
Location: Just Outside of Portland, OR

PostPosted: Tue Oct 04, 2005 5:27 am    Post subject: Reply with quote

Okay...no problem. BTW 5 miles isn't bad. It's almost impossible to judge "range" (man I hate that word) on any set up. Simply put, there are way too many criteria involved...part of which is what the contact is running for equipment.

And yes, start with the simple stuff first...such as the power input. Although it takes a little time, it's something that can make a huge difference. But on the other hand, may not make any difference at all. Just won't know until it's done. One step at a time.

As far as the SWR meter and use, I'd be happy to walk you through that as well. There isn't alot to it...but indeed, it can get confusing on what to do if not familiar with it.

As far as the radio goes, used is fine...it just lets me/us know we may be dealing with modifications or damage. So we can look to isolate those things as well.

Let us know if the power input wiring makes any difference at all, and we'll go from there.

Wink
Back to top
View user's profile Send private message
1fox2go
Member


Joined: 01 Dec 2004
Location: Fishersville, Virginia

PostPosted: Tue Oct 04, 2005 7:28 am    Post subject: Reply with quote

i will also does putting a tennis ball on your antenna to keep from hitting the body hurt its performance?

thanks for the help i couldnt find any instructions on how to use an SWR all i had to help was stevo who helped explain as best he could over the fone
_________________
96 Cherokee 7.5 inch TnT long arm Locked F/R, D44 rear, 4.56s, 35x12.50 Muds/36x12.50 TSLs
Back to top
View user's profile Send private message Send e-mail AIM Address
IBTJn
Moderator
Moderator


Joined: 31 Dec 2004
Location: Just Outside of Portland, OR

PostPosted: Tue Oct 04, 2005 9:49 am    Post subject: Reply with quote

1fox2go wrote:
i will also does putting a tennis ball on your antenna to keep from hitting the body hurt its performance?

thanks for the help i couldnt find any instructions on how to use an SWR all i had to help was stevo who helped explain as best he could over the fone

No problem...glad to help. And no, a tennis ball on the antenna is just fine. Any rubber, plastic, fiberglass, etc. is invisible to RF energy.

Let me or Phantum know when you are ready to tune the SWR's, and one of us will walk you through it.

Wink
Back to top
View user's profile Send private message
1fox2go
Member


Joined: 01 Dec 2004
Location: Fishersville, Virginia

PostPosted: Tue Oct 04, 2005 11:46 am    Post subject: Reply with quote

alrite...would it be too much of a hassle to pm or would it be a better idea to open a new thread and have it titled "how to tune your antenna with an swr" or something
_________________
96 Cherokee 7.5 inch TnT long arm Locked F/R, D44 rear, 4.56s, 35x12.50 Muds/36x12.50 TSLs
Back to top
View user's profile Send private message Send e-mail AIM Address
IBTJn
Moderator
Moderator


Joined: 31 Dec 2004
Location: Just Outside of Portland, OR

PostPosted: Tue Oct 04, 2005 12:32 pm    Post subject: Reply with quote

Well, hopefully nobody will care if I do it here. If they do, I'll PM it to you. Here is the abbreviated version (which should be fine for now) until I can get the write up to Kizer on L4J. The meter shown below is my bigger one, which I felt like it would be easer to see and reference for people. The brand of meter and style matters little...as long as the basic function is there.

1.) Connect a 3' Jumper cable as shown in between the CB and meter.



2.) Set the meter on "FWD" and key the mic (as shown) and adjust the FWD set knob (some smaller meters have only one knob) until the meter reaches the "Set" portion of the "SWR" scale.



3.) Unkey the microphone and switch to "REF" on the meter, and key the microphone again. (as shown)
This is your current SWR



To Adjust SWR's:
1.) Following the above proceedures, check channel #1 and channel #40 SWR's.

2.) If channel #1 is lower SWR than #40, the antenna needs to be shortened (which is very common on new antennas). If the opposite, it needs to be lengthened. (rare for new antennas)

3.) Adjust your antenna up or down a fraction of an inch at a time and re-check SWR's on both 1 & 40. Continue to adjust until desired SWR (preferrably under 1.5:1) is achieved on both 1 & 40.

Your SWR's are set.

If adjusting your antenna as listed above makes little to no difference, likely there is a grounding problem with the mount (hard mounts only).

Hopefully that will get you going. If you have more questions, just let one of us know.

Wink
Back to top
View user's profile Send private message
1fox2go
Member


Joined: 01 Dec 2004
Location: Fishersville, Virginia

PostPosted: Tue Oct 04, 2005 6:24 pm    Post subject: Reply with quote

sweet thanks
_________________
96 Cherokee 7.5 inch TnT long arm Locked F/R, D44 rear, 4.56s, 35x12.50 Muds/36x12.50 TSLs
Back to top
View user's profile Send private message Send e-mail AIM Address
Display posts from previous:   
Post new topic   Reply to topic     Forum Index -> Electronic All times are GMT - 8 Hours
Goto page Previous  1, 2, 3
Page 3 of 3

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Visit links4jeeps.com for write-ups, forums and clubs




Jeep®, Wrangler, Cherokee, Liberty and Grand Cherokee are copyrighted and trademarked to Chrysler LLC.
jeephorizons.com is not in any way associated with or endorsed by the Chrysler LLC.
All other content is copyright Jeep Horizons 2004-2008.
Tech write-ups Links Discussion board Land use News Site Map Terms of Use

Powered by phpBB © 2001, 2005 phpBB Group