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new cb set up is crap
hey guys
I have a cobra 75wtst well think its called that
with a maxrad nmo2700 antenna
larsen nmo lip mount
using it today on the highway and notice alot of probs.. first can't make out what any of the drivers are saying. I tryied to do a radio check and drivers would reply but I can't make them out.
lots of snow sound if you know what I mean.
when I step on the gas the rpm comes thru the speaker
when I use wipers lots of noise again.
my ground is connected to the main stud under the dash area. but looks like that spot is ****.
then next problem I had was when I unscrewed the larsen nmo the 3/4 thread came came off the rg58 cable.. ****en cheap stuff. so I installed my spare larsen nmo lip mount and using it now.
is it safe to say all my probs is from the ground ?
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Re: new cb set up is crap
Radio Shack sells noise filters. That will help with the alternator whine. A good ground is very important from an electrical and an RF stand point. CBs are sensitive to coax length (12, 15, 18ft) as well.
Go by a truckstop CB shop and get some ideas from them as to the way to fix your troubles. SWR is REAL important!!!
The snow you are speaking of is static or white noise. The better your antenna setup is the less noise you hear in most environments.
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Re: new cb set up is crap
Did you do a basic SWR check? Makes all the difference in the world?
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Re: new cb set up is crap
first time i did the swr i got it to like 1.2 but after removing the antenna from nmo mount for final trimming the best i can get now is 1.5
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Re: new cb set up is crap
Anyone that knows more than me please correct me, but when I get my new cb setup what I plan to do is ground it to the battery pole. Also make sure your trunk lid, hood, doors are closed, and you are in an area with no tall metal objects like: house antennas, buildings, etc.. Try to go to a park or something like that. If you can't get your SWR to get below 1.5 you may have to literally trim your antenna by cutting some if it off. I hope this helps.
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Re: new cb set up is crap
yup your right. I do know all about what ur trying to say.. so thanks for that.
so I was just working on the car. the ground I used was the main fuse panel stud.. turns out its a true ground but not as clean as going to the battery.
so I ran a slightly larger gauge ground wire to the battery( - ) started the car and reved it up tried wipers etc and the noise is gone. so looks like my first ground spot was a dirty signal.
so thats great.
I have 50 aches here so I drove into the field and checked the swr.
I got on ch40 1.1swr but on ch1 1.5swr. so looks like I ****ed up the whip by cutting a bit to much when I last did it with the bad ground. no biggee thou for now its good enough till I order this week a new black whip and will do a retune on it. thanks for the help :)
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Re: new cb set up is crap
1.5 is considered "tuned" according to guides on the Wilson and Firestick guides. Not perfect, but more than adequate. You should be pulling about 1.2-1.3 with 19 given the 1.5.
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Re: new cb set up is crap
just curious-- which black antenna did u order
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Re: new cb set up is crap
Glad everything worked out! I am also happy to hear that running a heavier gauge wire to true ground gets rid of the engine whine, I had the same problem in my old car.
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Re: new cb set up is crap
I know in the past main gound locations like the one I used is great for almost anything extra you add into the car. but I guess the nature of cb systems really do need super clean connection. so I guess battery was the only way to go. will test the cb out on thurdays when On the highway . hope its ok
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Re: new cb set up is crap
Bad ground will get you every time.
Glad to see you found the problem.
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Re: new cb set up is crap
you should install one of these too, it makes a world of difference.
http://www.sparkyscbshack.com/i//NF40.jpg
20 Amp Inline Noise Filter
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Re: new cb set up is crap
Ya last night I was so disappointed I am hoping this week when I use the highway it will be all mint.
ps to answer which black antenna. I am going to order the maxrad whip with part number BMATH.
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Re: new cb set up is crap
Quote:
Originally Posted by
languy99
do u know off hand the size of that? like 3"x3" or smaller?
and it goes thru in betwen my neg and pos right by the cb I take it?
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Re: new cb set up is crap
it's pretty small, you can hold it in the palm of your hand, and yes it is wires in series between the bat/ground and the CB.
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Re: new cb set up is crap
Quote:
Originally Posted by
autobel
Quote:
Originally Posted by
languy99
do u know off hand the size of that? like 3"x3" or smaller?
and it goes thru in betwen my neg and pos right by the cb I take it?
Any where in the power line.
It does not have to be next to the c.b.
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Re: new cb set up is crap
dont u mean power and ground?
like dont u cut the 2 wires right now somewhere and mount that in between?
i see there is 2 of them one is 10amp and the other is 20 which do i get?
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Re: new cb set up is crap
I would go with the higher power unit and I would mount it as close to the radio as possible becasue you want to try to prevent noise in the power lines and if you mount it close to the battery you are leaving lots of unfiltered lines with the potential to pick up noise.
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Re: new cb set up is crap
I would prob do it within 12" of the radio since I know where there is a some space i can zip tie it in
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Re: new cb set up is crap
I don't understand what the difference between the 10 amp and 20 amp is. What do amps have to do with it?
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Re: new cb set up is crap
the more watts a radio puts out the more amps it sucks from your car.
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Re: new cb set up is crap
Quote:
Originally Posted by
dewby
I don't understand what the difference between the 10 amp and 20 amp is. What do amps have to do with it?
If you have a stock radio that has no defective components you should not hit the 10 AMP mark
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Re: new cb set up is crap
Quote:
Originally Posted by
voyager7
Quote:
Originally Posted by
autobel
Quote:
Originally Posted by
languy99
do u know off hand the size of that? like 3"x3" or smaller?
and it goes thru in betwen my neg and pos right by the cb I take it?
Any where in the power line.
It does not have to be next to the c.b.
Back when (or in the day) they had a power filter that went on the alternator.
So all electronics had filtered power.
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Re: new cb set up is crap
Quote:
Originally Posted by
voyager7
Quote:
Originally Posted by
voyager7
Quote:
Originally Posted by
autobel
Quote:
Originally Posted by
languy99
do u know off hand the size of that? like 3"x3" or smaller?
and it goes thru in betwen my neg and pos right by the cb I take it?
Any where in the power line.
It does not have to be next to the c.b.
Back when (or in the day) they had a power filter that went on the alternator.
So all electronics had filtered power.
Honestly why am I hearing so much more noise in cars lately? You would think I would hear less. I know one thing that adds noise is frickin Cell Phone and IPOD car chargers.
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Re: new cb set up is crap
With the c.b in the 03 Cobra there is no noise.
I put the same c.b in the 01 van (E 150) and there is noise, go figure.
I had to buy a noise filter when I was in FL to keep the c.b quiet.
Worked great after that.
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Re: new cb set up is crap
Quote:
Originally Posted by
STiMULi
Quote:
Originally Posted by
voyager7
Back when (or in the day) they had a power filter that went on the alternator.
So all electronics had filtered power.
Honestly why am I hearing so much more noise in cars lately? You would think I would hear less. I know one thing that adds noise is frickin Cell Phone and IPOD car chargers.
I should of said you could buy a noise filter to go on the alternator.
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Re: new cb set up is crap
the problem is that CB radios are on the AM bandwidth ( I think) and they are very susceptible to noise, turn on your cars radio, hear the static. Most cars don't need to worry about have really clean power because almost everything in a car is digital and digital means there is no noise to worry about.
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Re: new cb set up is crap
I found a must read for newbies and us long tiime owners as well.
Things to think about:
The Ultimate Guide to 11 Meter CB Antennas
Actually the whole site is well done.
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Re: new cb set up is crap
I will see how it is tomorw on the highway. I will try stereo wipers etc. if its ok I wont bother if I get a little noise I will go with a 10amp.
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Re: new cb set up is crap
Are you using the internal speaker or an external add on? I've heard rough things about some of the 75's speakers, as it being a hit or miss in Quality control.
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Re: new cb set up is crap
I never tired it with handset mic. my car was set up for my old radio uniden so i already have a uniden external speaker I am using works perfect
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Re: new cb set up is crap
Quote:
Originally Posted by
STiMULi
Great find.
Here is one I found a year or so ago.
Tips and tricks on how to build your own CB Antennas.
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Re: new cb set up is crap
Quote:
Originally Posted by
voyager7
I like it!
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Re: new cb set up is crap
well i had a chance to use it tonight .. still getting noise and the bar graph goes up a bar to when u use the wipers and turn on the stereo.. is my prob ground related or power?
or is one of those things that nothing more i can do to fix it then to get a filter like we talked about?
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Re: new cb set up is crap
this is what I know, a group problem is constant noise ( very loud static) no matter what you do. A noise the comes in when you use something means noise on the power side (usually AC noise). What those filters do is take the AC noise and push it to ground leaving clean DC power.
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Re: new cb set up is crap
Quote:
Originally Posted by
autobel
well i had a chance to use it tonight .. still getting noise and the bar graph goes up a bar to when u use the wipers and turn on the stereo.. is my prob ground related or power?
or is one of those things that nothing more i can do to fix it then to get a filter like we talked about?
Buy the filter.
Any car stereo shop should have them. Got mine from Car Tunes for $20.
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Re: new cb set up is crap
local places dont have those here. I will just order from ebay..
10amp model should be good right?
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Re: new cb set up is crap
Lots of talk about your ground, but not about the 12V+ connection. Where are you getting your power from?
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Re: new cb set up is crap
CB & FRS Radios FAQ
Quote:
Question: I get noise on my radio when I connect it in my vehicle; how do I troubleshoot it?
Answer: The first thing to check is if the noise is still present if you disconnect the antenna from the CB radio.
If the noise goes away, then there may be a component that needs to be shielded, or the antenna cable needs to be moved to a location where the interference is minimized. As well, a ground strap may need to be installed that connects the hood to the firewall.
If the noise doesn't minimize, then the problem may be caused by noise through the power or ground connection. A suggestion is to ground to the engine block and use the positive battery terminal as the power source for the CB radio.
Additional filtering may also be necessary. We offer several automotive noise filters under Audio, Automotive Electronics, 12 Volt.
My car makes noise in my CB from the wipers, ignition, and ABS (a whirring noise when it self-tests and activates while driving). I tried one of those power filters and it did bugger all, because the noise was actually coming in through the antenna. It was pretty bad with a Cobra 75; my solution was to get a Uniden that has better filtering...
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Re: new cb set up is crap
Quote:
Originally Posted by
autobel
local places dont have those here. I will just order from ebay..
10amp model should be good right?
Yep should work just fine.
