CB Install - Getting Feedback Noise

Gblabla

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Help me figure out what I did wrong with what seems to be a very straightforward installation.

I wired the power to the CB directly from the connection block behind the fuse block under the hood and grounded to one of the chassis bolts in the glovebox.

The CB is getting all kinds of feedback when the engine is running that increases as the RPM increases. I tested by running a ground directly to the battery and that didn't help at all.

Any thoughts on where the problem is and what I may need to do to fix? This all seemed so easy so a little stumped here.
 
Help me figure out what I did wrong with what seems to be a very straightforward installation.

I wired the power to the CB directly from the connection block behind the fuse block under the hood and grounded to one of the chassis bolts in the glovebox.

The CB is getting all kinds of feedback when the engine is running that increases as the RPM increases. I tested by running a ground directly to the battery and that didn't help at all.

Any thoughts on where the problem is and what I may need to do to fix? This all seemed so easy so a little stumped here.
Have you tried running a positive wire all the way to the battery as well? Run them on the same path if you can. (Be sure to fuse it if you install it permanently. Should be fine to test without a fuse.)
 
Describe the "feedback" sound you're hearing. Is it static from ignition spark?

It is a rough static sound that almost sounds like a 2 stroke motorcycle coming through the speaker.

I can easily try the power and ground directly to the battery as a test but the power lead is only one short cable away from the battery as it sits.
 
It is a rough static sound that almost sounds like a 2 stroke motorcycle coming through the speaker.

I can easily try the power and ground directly to the battery as a test but the power lead is only one short cable away from the battery as it sits.
Are you running stock spark plugs, or could someone have installed non-resistor type spark plugs seeking more performance?
 
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Good question. Jeep is new to me so I'll take a look and see what plugs are in it.

So you are saying I won't get an extra 20HP with non-resistor plugs?? 😁
Non-resistor type plugs and low-resistance ignition wiring will definitely cause static in AM and CB radios. Your '05 doesn't use ignition wiring but maybe the previous owner cluelessly installed non-resistor spark plugs.
 
Help me figure out what I did wrong with what seems to be a very straightforward installation.

I wired the power to the CB directly from the connection block behind the fuse block under the hood and grounded to one of the chassis bolts in the glovebox.

The CB is getting all kinds of feedback when the engine is running that increases as the RPM increases. I tested by running a ground directly to the battery and that didn't help at all.

Any thoughts on where the problem is and what I may need to do to fix? This all seemed so easy so a little stumped here.

I initially installed my CB with a power wire picked up from the fuse panel behind the glovebox and a ground in the wheel well. I had a lot of ignition whine, so I eventually ended up running both the power and ground direct to the battery. It sounds much cleaner now. I put an extra hole behind the glovebox and installed a 3/4" grommet I found in a little kit from autozone.

Edit: I also initially used 16 gauge wire direct to the battery terminals and it still didn't sound great. Based on some of Jerry's advice from other threads I changed it all over to 10 gauge and it that is what finally cleaned up the signal.
 
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I always hated this problem back when I was installing radios on cars and boats. I use to run an LC (inductor/capacitor) on the power leads sometimes.
Also, is it possible that your power wires are running too close to a noise source? For s--ts and giggles, try running your wires straight to the battery, but briefly lifting them up away from the engine. If the noise abates a little you can move them to another less noisy route. When I installed Loran C, (100KHz), I had to run the coupler wires on the opposite side of the boat/yacht from the depth Sounders (50-200KHz) or I got interference. May work, may not. Just something to chew on. You may need to find a radio shop to get what you need.