Wiring power and antenna through firewall question

[Roofus]

Friends, just a quick question before I run my power wiring for my air compressor through the firewall. As you can see in the pic, I’m already running my GMRS antenna cable through the firewall to a mirror mounted antenna. Just curious if anyone knows if I’m risking interference by running the ARB wiring harness next to my antenna cable? Thanks!

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[BigHoof]

I would probably not run them together. There is a place to run a cable through the firewall just above the big wire harness. There is a nipple that you can cut the end off of. It's tight getting there but doable. I had to use because the upper grommet is for the clutch.

 

[Roofus]

Yeah, that’s the problem. I used the little free grommet for my GMRS cable. If you zoom in to my picture, you can see the antenna cable going through that little grommet that everyone uses. So that means I need to figure out a different way to route my ARB harness if that risks interference.

 

[RagnarKon]

Yeah, that’s the problem. I used the little free grommet for my GMRS cable. If you zoom in to my picture, you can see the antenna cable going through that little grommet that everyone uses. So that means I need to figure out a different way to route my ARB harness if that risks interference.

As @BigHoof said there is a dedicated path specifically for aftermarket wiring.

Those of us with manual transmissions don't have that handy little firewall plug that you have, because it's occupied by the clutch, so we are basically forced to use the dedicated path Ford created. You can watch me fight through it on my subwoofer install video if you want to get a sense for what you'll be in store for.



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All that said... we're talking DC current here on your compressor, so the only chance you have for interference is when the compressor kicks on and off. It isn't like AC current where there is continual chance for interference.

 

[Roofus]

Perfect! Thank you. I did not know there was a grommet for pass throughs on the factory harness and I really did not want to cut into that boot.

 

[GroovyGeek]

Friends, just a quick question before I run my power wiring for my air compressor through the firewall. As you can see in the pic, I’m already running my GMRS antenna cable through the firewall to a mirror mounted antenna. Just curious if anyone knows if I’m risking interference by running the ARB wiring harness next to my antenna cable? Thanks!

Mmm do you absolutely need to talk on the GMRS while the compressor is running? If the answer is no you have nothing to worry about. Compressor off = no interference

 

[Roofus]

Mmm do you absolutely need to talk on the GMRS while the compressor is running? If the answer is no you have nothing to worry about. Compressor off = no interference

I try to only speak to my good friends with as much background noise as possible to add to the off-grid ambiance.

No, you make a good point. I can't see that scenario happening too often. However, now I'm wracking my brain to think if there's anything else I might need to run through that autotrans only grommet that might create a future issue. Can't think of anything atm, but I'm also wondering if that pass through from the main harness boot would supply enough insulation from effecting the antenna cable... i.e. I'm wondering if I should go back and re-route the antenna wire through the main harness boot grommet, and leave the autotrans only grommet for power/ground wiring.

 

[BigMac]

I was a radio tech for decades and ran into these types of problems constantly. I agree with GroovyGeek on the timing issue. GMRS is FM and not particularly susceptible to the noise that could be generated by your compressor. There is probably more random RF being generated by all the electronics in your Bronco in the first place. Unless you have the absolute cheapest antenna coax on your radio I doubt you will have any issues. Go for it. I would make sure you don't have a parallel run with the coax and the power wire and insure you have a good ground on your antenna, but that's about it.

 

[BigHoof]

Here is a link to a picture of the nipple @RagnarKon and I were referencing. Once you get the nipple cut off under the hood at the marked line, I found that there was also a little more material that had to be cut from the port on the inside.

https://www.bronco6g.com/forum/thre...iring-through-the-firewall.41514/post-2127239

 

[Roofus]

Thanks, y’all!

 

[ksdon]

Just another idea is to use copper grounding braid to wrap your antenna cable as additional shielding. https://www.amazon.com/Tinned-Coppe...ix=copper+grounding+braid,aps,120&sr=8-4&th=1

 

[Roofus]

Just another idea is to use copper grounding braid to wrap your antenna cable as additional shielding. https://www.amazon.com/Tinned-Copper-Braided-Sleeving-Diameter/dp/B01BIBQ940/ref=sr_1_4?crid=2UCH9SG9HJ6DJ&keywords=copper+grounding+braid&qid=1704657394&sprefix=copper+grounding+braid,aps,120&sr=8-4&th=1

Ooo… maybe I should just wrap it all the way to the receiver in case the coax is touching any wires behind the dash to under the glove box.

 

[Brian_B]

Ooo… maybe I should just wrap it all the way to the receiver in case the coax is touching any wires behind the dash to under the glove box.

Can't hurt. Although isn't antenna wiring usually shielded internally? Usually a bare braided wire or foil that runs inside an outer sleeve, around the inner wire. The cable shielding is supposed to be grounded at one end only - if you ground it at both ends weird things can happen.

https://www.mouser.com/pdfdocs/alphawire-Understanding-Shielded-Cable.pdf

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