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C.B. noise Update (its Still there)

Depdog

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O.k. here is what I have done so far. The c.b. is powered straight from the battery, both positive and negative. The battery is grounded to the engine, chassis and frame. The ignition is grounded to the chassis and the battery (going to the battery as well was the crane techs idea, it did help some). Tried 2 different antennas, one is bolted to the tire carrier and the other a magnetic mount. When I pull the magnetic one off the body the noise stops, so does the reception. I can unhook the antenna wire from the back of the c.b. and the noise stops. I installed the biggest noise suppressor that Radio Shack has and the noise is still there. When I rev the engine the noise climbs and lowers with r.p.m. Un hooked the alterntor, noise is still there.

The only thing else that the crane tech can come up with is to put a 38,000 mf (micro fared-dont have a clue what that is) 16 volt capacitor in the positve wire of the ignition. Cant find one here and Crane wants 30 bucks for it. Its about the size of a beer can. I am trying to figure out how or if this would help before I drop the $$ on it. Does anybody know?

It goes in the main power wire for the ignition between the battery and the ignition itself.

This is the most frustrating thing that I have ever fooled with.

Any and all help greatly appreciated.

Depdog

<font color=blue>"Lead, Follow, or BECOME the Trail"</font color=blue>

http://depdogsk5.coloradok5.com
 
some ideas...

Remember the old points distributors, they had a condenser (cap rated in micro-farads) bolt it to the alternator case, then attach the wire to the big red wire on the alternator. BTW did you unhook the alternator completely?
 
Is the sound sort of like a squealing? When my truck starts up, and I have the CB on, it squeals like mad, untill the truck is idling.. I dunno if it's supposed to do that, since I'm pretty new to the world of C.B.s. I dunno what in the engine causes the C.B. to emmit that sound.. but it dissapears after the engine idles. I dunno this helps much, but I figured I'd share my experiance.

http://billybob.coloradok5.com
It's all fun 'n games, till someone gets stuck.
 
Do you have a powerful capacitor on your distributor, or some aftermarket ignition? Obviously your ignition system is emitting some kind of wave, either electromagnetic or someother kind of wave that is interferring with your C.B. If i see the guy that helps me with my C.B. I'll ask him what he thinks. He is really good at this kind of stuff. Later - Doug

Doug Krebs
 
Thanks I would appreciate it. Its a Crane HI-6 ignition and its pretty powerful. The ignition box is under the dash mounted to the air conditioner box.

C.B. is on top of the dash pad.

Depdog

<font color=blue>"Lead, Follow, or BECOME the Trail"</font color=blue>

http://depdogsk5.coloradok5.com
 
I unhooked the alternator completly, was running off the battery, did not make a difference, I was pretty sure it was the ignition but I wanted to take the alternator out of the equation for sure.

Depdog

<font color=blue>"Lead, Follow, or BECOME the Trail"</font color=blue>

http://depdogsk5.coloradok5.com
 
First of all what type of C.B. do you have? Second run your positive direct to your battery(use a in-line fuse). Third run the shortest ground as possible, but keep in mind it needs to be a solid ground. Next make sure u have the antenna mount mounted to a solid part of your truck anywhere u can get a good solid ground (tire mount is probably not a ideal place due to lack of ground stability). Next throw away your magnetic antenna, if u need your antenna to have an easy dismount go to your closest truck stop and they will carry a quick disconnect for about $5.
The absolute best set up is 18' feet of coaxial cable and a 102" inch steel whip. At least get a steel whip no fiberglass and 18' feet of cord. U should not need any noise suppressor they r about as helpfull as a boat anchor. What type of C.B. do u have?

Professional JEEP EATER, it's a population control thing
 
BillyBob
Try your best to turn of your C.B. before turning off your truck and/or before starting it. You can blow a condinsor inside of your C.B. which usually will cost about $50bucks to fix, thats $5o bucks you could be spending on a u-joint or something of the sorts.

Professional JEEP EATER, it's a population control thing
 
You may have thought of this already, but if not, replace your ignition wires with radio-suppression wires. That's most likely where any ignition noise os coming from. The ignition box itself should already be shielded, so your wires are probably the culprit.
 
But are they radio suppression wires? Not all ignition wires are. Many "racing"-type are not, because the radio suppression interferes with high-rpm operation (shouldn't be a problem w/ slow-moving 4x4s).
 
Its a Cobra(forgot the model number, but its the one with the speaker on the front and the cheapest one with sound tracker) the power wire and the ground are straight to the battery (yes the power wire is fused) Have 18 foot of cable and the antenna is mounted to a tire carrier that I built and its also grounded to the frame fromt the tire carrier by wire. The magnetic mount antenna I just used for testing purposes, so I could rule out my solid mounted one, I dont use it.

Depdog

<font color=blue>"Lead, Follow, or BECOME the Trail"</font color=blue>

http://depdogsk5.coloradok5.com
 
After reading though all the post above. I see that you have done evey thing right. the rig gets power from the battery and is grounded to the battery, The key was the mag mount you tested with when you used it and pulled it off the blazer the noise stopped. This means that the noise is coming in the ant. not the power wires so for get all the power wire fix's you have that down so move on. Most CB's come with cheap coax its very small and has a foil sheild the shield is not even always grounded as it should be, Use a good coax with a wire shield, with the ends soldered on not crimped on! Run the cabel in a fairly clean path DONT COIL EXTRA CABEL! do not kink the cabel in any way, The cabel is a part of the ant, and in you case its picking up the ECM's switchings.

I understand the jeep thing I drive a BLAZER!!

Ken
 
Hey Dep,

Have you followed your coax from the CB to your Antenna inspecting it for cuts or wear, where it could be ground or getting interference? Or also cehck the ground and power wire for the same things.

HTH

Mike
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1982 GMC Jimmy - <font color=green>Emmett</font color=green>
http://emmett.coloradok5.com
 
O.k. did that, no kinks or coils in the wire. Its new and its a big thick gray one that I got at the truck stop, it has the ends soldered on as well. Still got the damn noise. Does anybody know if they make an antenna filter or something like that?

Depdog

<font color=blue>"Lead, Follow, or BECOME the Trail"</font color=blue>

http://depdogsk5.coloradok5.com
 
Depdog
Is your tire mount a swing or is it a solid mount? Antenna is still mounted to it right? What kinda ant do u have? What model cobra? What does the sound, sound like a squeal,a loud fuzzy noise, distortion when you key up?

Professional JEEP EATER, it's a population control thing
 
yes there are fillters for the ant. Find a good shop and take it there. Look for a Ham shop npt a cb one

I understand the jeep thing I drive a BLAZER!!

Ken
 
Man o' man.... Have you tried in line noise supressors in the power, ground,coax?

Other than that I am going to have to think about this one a little more.

Mike
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1982 GMC Jimmy - <font color=green>Emmett</font color=green>
http://emmett.coloradok5.com
 
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