Stumped on interferance problem

jurick · 05-15-2008, 09:09 PM

Well I have had my CB installed for a while but finally got around to messing around with it. Well I have run into some major problems.

With the engine running and radio on I get a lot of interferance I also can hear myself though the speakers and the sub woofer I installed when talking though the mic.

I already have the CB directly connected to the battery and a line conditioner on the cb power line. I have checked the ground and have a good ground on both the cb and the antenna. I have checked SWR and it has been adjusted and set right.

So basicly at this point I have no clue what to do next what is really confusing me is the sound from the cb mic coming though all the speakers in my ex.

I also forgot to mention that when I had my SWR meter connected the interferance almost completely went away but I can't always have that connected because it would get destroyed from going over bumps and offroading.

So feel free to give some suggestions on what to do to solve this problem.

**rizzjc** · 05-15-2008, 10:04 PM

What type of CB do you have (make and model)? Where is it mounted? You said you have a sub you installed, but do you have the factory radio? Maybe post a pic of your setup.

**Tbars4** · 05-15-2008, 10:08 PM

...Also, if you can explain where exactly you ran your antenna wire...

**rizzjc** · 05-15-2008, 10:10 PM

Here's a good sticky as well, about noise, and tracking it down:
http://www.explorerforum.com/forums/...d.php?t=136929

Thanks tbars. Definitely, antenna routing is key.

jurick · 05-15-2008, 10:33 PM

The cb is a old cobra cb I have no clue what model it is. It is mounted on the hump right below the 12volt power plug, that is located on the passenger side right infront of the seat on my second gen.

The antenna cable was originally run down the side with the wireing harness to the rear on the drivers side but I pulled that out and have it laying out running from my antenna directly to the cb. The antenna is mounted right next to the rear drivers side taillight, it is a 2' firestik antenna. I am using cable that is rated to military spec.

Edit: I forgot to add that it is a aftermarket radio. I also rewired part of the old system because of the main control for the stock radio being in the rear. I am still stumped on how my voice from the cb is getting into my radio even when I have it on my Ipod or CD. The noise that it puts out though the speakers is also effected by how high I have the volume on the radio.

I will also try to get some pictures tommorrow.

**rizzjc** · 05-16-2008, 06:06 AM

Just a thought. Since you have an ipod, do you have on it hardwired into the radio, or are you possibly using one of those FM transmitters? Just a thought. You need to look and see where all of your wires are running, with respect to everything else. Maybe try moving the radio somewhere (temporarily) to see if it still does it. Does it matter if the vehicle is running or not?

jurick · 05-16-2008, 09:01 AM

The ipod is hardwired into the radio and so I am not using a FM transmitter. I was thinking that after I have a power conditioner right next to the radio on the power line that I shouldn't be getting interference from that or am I incorrect? Also it does not matter if the engine is on, if the radio is on I get interference but it does seem to be a little worse with the engine on but its mostly the radio.

I am going to try to move the radio around today to see if it will make a difference(I knew that I should not of hardwired that thing).

**rizzjc** · 05-16-2008, 12:28 PM

When you transmit on the CB, do you hear it on the radio?

jurick · 05-16-2008, 02:32 PM

Yea, when I transmit I hear it on the radio.

I fixed part of the interference problem today after rewiring the whole thing and testing to figure out which setup was the best. I still have a little interefernce and I still have the sound coming though the radio when I transmit though, which I am still trying to figure out how it is entering the system I even moved the cb away from the radio and it still does it. The wires for the cb are directly connected to the battery and grounded to the body. So at this point I have got myself really confused because it has to be entering though the head unit because I can control how loud the volume that comes out of the speakers when I transmit is from the volume on the head unit.

**rizzjc** · 05-16-2008, 03:11 PM

What are you using for ground? Did you try running both positive and ground to the battery? Do you have any buddies you could borrow a CB from to test with their's to see if you still have the same problem? Maybe you just have an old CB that is just radiating like crazy. But let us know about the ground.

**Tbars4** · 05-16-2008, 03:15 PM

...I second the old cb comment...I have heard this before about the old cobras and would also suggest trying another radio too...The newer ones still do it if the cb is close to the aftermarket HU or the antenna wire is close to the stock speaker wires...

jurick · 05-16-2008, 10:52 PM

Well for the ground it is connected to the body by the screw that holds the cb mounting bracket in place. I have tried connecting both the hot and ground to the battery and connecting the ground to the battery made no difference and the hot is permanatly connected.

That is what I was afraid of that I might have a bad cb. Guess its time to see if that is the case, I will try to either borrow or buy a new one soon. Hopefully that will solve the problem.

05-15-2008, 09:09 PM	#1
jurick Wannabe Elite Explorer Maryland 97 Eddie Bauer Join Date: Nov 2007 Posts: 87 Vehicle Specs (Original Poster)	Stumped on interferance problem Well I have had my CB installed for a while but finally got around to messing around with it. Well I have run into some major problems. With the engine running and radio on I get a lot of interferance I also can hear myself though the speakers and the sub woofer I installed when talking though the mic. I already have the CB directly connected to the battery and a line conditioner on the cb power line. I have checked the ground and have a good ground on both the cb and the antenna. I have checked SWR and it has been adjusted and set right. So basicly at this point I have no clue what to do next what is really confusing me is the sound from the cb mic coming though all the speakers in my ex. I also forgot to mention that when I had my SWR meter connected the interferance almost completely went away but I can't always have that connected because it would get destroyed from going over bumps and offroading. So feel free to give some suggestions on what to do to solve this problem.

05-15-2008, 10:04 PM	#2
rizzjc Scubajoe - Radio Mod Garner, NC '97 AWD V8 XLT Join Date: Jul 2005 Posts: 3,247 Vehicle Specs	What type of CB do you have (make and model)? Where is it mounted? You said you have a sub you installed, but do you have the factory radio? Maybe post a pic of your setup. __________________ *Joe, N1LVN* '97 XLT AWD V8 STOCK Amsoil Synthetics throughout. Amsoil Ea air filter. Bilsteins. Scanguage. Search ExplorerForum

05-15-2008, 10:08 PM	#3
Tbars4 Offroad Moderator anaheim hills,california 95 ranger 4x4/ 91 X 4x4 Join Date: Mar 2007 Posts: 21,956 Vehicle Specs	...Also, if you can explain where exactly you ran your antenna wire... __________________ I have Rocks in my head. What's in yours? '95 ranger xl 4x4 2.3L std cab, 2 sticks Ranger RegistryThe Squirrel '91 4x4=To much to list, much more to add.. Project "X" and more Pics & Mod's List How to: Wheels,Tires, & Lifts... Buy Explorerforum.com Items here

05-15-2008, 10:10 PM	#4
rizzjc Scubajoe - Radio Mod Garner, NC '97 AWD V8 XLT Join Date: Jul 2005 Posts: 3,247 Vehicle Specs	Here's a good sticky as well, about noise, and tracking it down: http://www.explorerforum.com/forums/...d.php?t=136929 Thanks tbars. Definitely, antenna routing is key. __________________ *Joe, N1LVN* '97 XLT AWD V8 STOCK Amsoil Synthetics throughout. Amsoil Ea air filter. Bilsteins. Scanguage. Search ExplorerForum

05-16-2008, 06:06 AM	#6
rizzjc Scubajoe - Radio Mod Garner, NC '97 AWD V8 XLT Join Date: Jul 2005 Posts: 3,247 Vehicle Specs	Just a thought. Since you have an ipod, do you have on it hardwired into the radio, or are you possibly using one of those FM transmitters? Just a thought. You need to look and see where all of your wires are running, with respect to everything else. Maybe try moving the radio somewhere (temporarily) to see if it still does it. Does it matter if the vehicle is running or not? __________________ *Joe, N1LVN* '97 XLT AWD V8 STOCK Amsoil Synthetics throughout. Amsoil Ea air filter. Bilsteins. Scanguage. Search ExplorerForum

05-15-2008, 10:33 PM	#5
jurick Wannabe Elite Explorer Maryland 97 Eddie Bauer Join Date: Nov 2007 Posts: 87 Vehicle Specs (Original Poster)	The cb is a old cobra cb I have no clue what model it is. It is mounted on the hump right below the 12volt power plug, that is located on the passenger side right infront of the seat on my second gen. The antenna cable was originally run down the side with the wireing harness to the rear on the drivers side but I pulled that out and have it laying out running from my antenna directly to the cb. The antenna is mounted right next to the rear drivers side taillight, it is a 2' firestik antenna. I am using cable that is rated to military spec. Edit: I forgot to add that it is a aftermarket radio. I also rewired part of the old system because of the main control for the stock radio being in the rear. I am still stumped on how my voice from the cb is getting into my radio even when I have it on my Ipod or CD. The noise that it puts out though the speakers is also effected by how high I have the volume on the radio. I will also try to get some pictures tommorrow.

05-16-2008, 09:01 AM	#7
jurick Wannabe Elite Explorer Maryland 97 Eddie Bauer Join Date: Nov 2007 Posts: 87 Vehicle Specs (Original Poster)	The ipod is hardwired into the radio and so I am not using a FM transmitter. I was thinking that after I have a power conditioner right next to the radio on the power line that I shouldn't be getting interference from that or am I incorrect? Also it does not matter if the engine is on, if the radio is on I get interference but it does seem to be a little worse with the engine on but its mostly the radio. I am going to try to move the radio around today to see if it will make a difference(I knew that I should not of hardwired that thing).

05-16-2008, 12:28 PM	#8
rizzjc Scubajoe - Radio Mod Garner, NC '97 AWD V8 XLT Join Date: Jul 2005 Posts: 3,247 Vehicle Specs	When you transmit on the CB, do you hear it on the radio? __________________ *Joe, N1LVN* '97 XLT AWD V8 STOCK Amsoil Synthetics throughout. Amsoil Ea air filter. Bilsteins. Scanguage. Search ExplorerForum

05-16-2008, 02:32 PM	#9
jurick Wannabe Elite Explorer Maryland 97 Eddie Bauer Join Date: Nov 2007 Posts: 87 Vehicle Specs (Original Poster)	Yea, when I transmit I hear it on the radio. I fixed part of the interference problem today after rewiring the whole thing and testing to figure out which setup was the best. I still have a little interefernce and I still have the sound coming though the radio when I transmit though, which I am still trying to figure out how it is entering the system I even moved the cb away from the radio and it still does it. The wires for the cb are directly connected to the battery and grounded to the body. So at this point I have got myself really confused because it has to be entering though the head unit because I can control how loud the volume that comes out of the speakers when I transmit is from the volume on the head unit.

05-16-2008, 03:11 PM	#10
rizzjc Scubajoe - Radio Mod Garner, NC '97 AWD V8 XLT Join Date: Jul 2005 Posts: 3,247 Vehicle Specs	What are you using for ground? Did you try running both positive and ground to the battery? Do you have any buddies you could borrow a CB from to test with their's to see if you still have the same problem? Maybe you just have an old CB that is just radiating like crazy. But let us know about the ground. __________________ *Joe, N1LVN* '97 XLT AWD V8 STOCK Amsoil Synthetics throughout. Amsoil Ea air filter. Bilsteins. Scanguage. Search ExplorerForum

05-16-2008, 03:15 PM	#11
Tbars4 Offroad Moderator anaheim hills,california 95 ranger 4x4/ 91 X 4x4 Join Date: Mar 2007 Posts: 21,956 Vehicle Specs	...I second the old cb comment...I have heard this before about the old cobras and would also suggest trying another radio too...The newer ones still do it if the cb is close to the aftermarket HU or the antenna wire is close to the stock speaker wires... __________________ I have Rocks in my head. What's in yours? '95 ranger xl 4x4 2.3L std cab, 2 sticks Ranger RegistryThe Squirrel '91 4x4=To much to list, much more to add.. Project "X" and more Pics & Mod's List How to: Wheels,Tires, & Lifts... Buy Explorerforum.com Items here

05-16-2008, 10:52 PM	#12
jurick Wannabe Elite Explorer Maryland 97 Eddie Bauer Join Date: Nov 2007 Posts: 87 Vehicle Specs (Original Poster)	Well for the ground it is connected to the body by the screw that holds the cb mounting bracket in place. I have tried connecting both the hot and ground to the battery and connecting the ground to the battery made no difference and the hot is permanatly connected. That is what I was afraid of that I might have a bad cb. Guess its time to see if that is the case, I will try to either borrow or buy a new one soon. Hopefully that will solve the problem.