Ham Radio Noise

[bhaner]

Anyone else running HAM radios in a JKU notice RF interference when the key is on?

Seems to mostly be on the 2 meter band.

If I turn the key off it goes away.

Turn the key to ACC or RUN and it comes back. Still there with the engine running.

I can't trace it to anything like LED lights or a bad component.

I picked up a Nano VNA antenna analyzer and can't seem to find anything wrong there.

Does it with the antenna installed or removed. The static also goes away when I remove the coax from the radio.

Feed power doesn't seem to change it. I even ran on an external battery with no change.


Currently the radio is installed under the drivers seat. The antenna wire travels under the floor mat and carpet to the passenger side. It then follows the side of the wheel well all the way back to the tailgate. It enters the tailgate with all the other wires and exits out the hole on the right of the gate vent.

Is there something in the back of the Jeep that could cause interference when the key is on?

 

[wayoflife]

Definitely need to have the radio's positive and negative lead go right to the battery. If you attach it to any other power source of ground, you can get noise. Also, it's critical to make sure that the coax cable is NOT following any other electrical harness as that can transmit noise as well. Even something as dumb as a brake light can cause noise.

 

[bhaner]

Definitely need to have the radio's positive and negative lead go right to the battery. If you attach it to any other power source of ground, you can get noise. Also, it's critical to make sure that the coax cable is NOT following any other electrical harness as that can transmit noise as well. Even something as dumb as a brake light can cause noise.

Power leads do go direct to the battery.

Only place the antenna coax comes in contact with other wires is when it gets to the tailgate. I think the wires going inside the tailgate are just for the lock and door open/closed switch.

Maybe the open/closed switch gets energized when the key turns on?

I really don't like having an antenna on the front of the fender because things hit it... But I am running out of ideas for making the tailgate antenna work.

 

[Bullwinckle]

Not sure how different a HAM and a CB is but I had that happen a few years back with my old JKs CB paired with poor communication. I found it to be a pinched antenna wire back near the tailgate. Not sure if this will help just a thought.

 

[bhaner]

I got a new antenna coax today and gave it a shot. Just hooking the antenna up and leaning it up against the wall I still have all kinds of interference once I turn the key on.

I figured I would start pulling fuses until I found what was causing the noise. I started with things on the list that I thought would be on in ACC mode. About the 4th fuse in the noise went away!

It was the fuse for the radio/head unit. I have one of the Alpine restyle head units.

I started pulling it out of the dash. I put the fuse back in and started unhooking modules until the noise quit again.

I had just about everything unhooked including the screen and the power to the head unit brain. However once I unhooked the Maestro module the noise quit.

I think I found the problem! I am going to make a few phone calls and see if this is a known issue. Maybe even get a replacement module on the way.

 

[CalSgt]

Wow... Glad you found the problem, I've had issues with cheap amps and cables causing buzzing over the years but not usually quality equipment

 

[wjtstudios]

Great detective work Byron. That’s crazy

 

[Bierpower]

I got a new antenna coax today and gave it a shot. Just hooking the antenna up and leaning it up against the wall I still have all kinds of interference once I turn the key on.

I figured I would start pulling fuses until I found what was causing the noise. I started with things on the list that I thought would be on in ACC mode. About the 4th fuse in the noise went away!

It was the fuse for the radio/head unit. I have one of the Alpine restyle head units.

I started pulling it out of the dash. I put the fuse back in and started unhooking modules until the noise quit again.

I had just about everything unhooked including the screen and the power to the head unit brain. However once I unhooked the Maestro module the noise quit.

I think I found the problem! I am going to make a few phone calls and see if this is a known issue. Maybe even get a replacement module on the way.

View attachment 361495

I'm nowhere near an electrical guru but I'm curious, bear with me. The maestro is for steering wheel controls, is it not? I can't imagine that it is emitting any signal (ie bluetooth). So interference would have to be traveling either through the wiring or unintended emission from the module. Could you just wrap some foil around the module and stick it back in the dash if it's emitting interference? I know lots of backup cameras have a foil shield around the wires to keep from distorting the picture.

 

[bhaner]

I'm nowhere near an electrical guru but I'm curious, bear with me. The maestro is for steering wheel controls, is it not? I can't imagine that it is emitting any signal (ie bluetooth). So interference would have to be traveling either through the wiring or unintended emission from the module. Could you just wrap some foil around the module and stick it back in the dash if it's emitting interference? I know lots of backup cameras have a foil shield around the wires to keep from distorting the picture.

LMAO! I actually thought of the tin foil fix. It may have helped a little... But not enough to call it a fix.

Yeah. The module in this setup does a ton. It won't even power on the head unit without it. Connects to the factory amp, canbus, etc. But you are correct. It shouldn't have any bluetooth/wifi signal coming out of it.

 

[bhaner]

The module even has a small relay of some sort in it. I can hear it click and then the noise starts on the ham radio.

 

[Bierpower]

The module even has a small relay of some sort in it. I can hear it click and then the noise starts on the ham radio.

I wonder if the relay is kicking on a GPS antenna or Satellite radio.

 

[Snboarder113]

I'm nowhere near an electrical guru but I'm curious, bear with me. The maestro is for steering wheel controls, is it not? I can't imagine that it is emitting any signal (ie bluetooth). So interference would have to be traveling either through the wiring or unintended emission from the module. Could you just wrap some foil around the module and stick it back in the dash if it's emitting interference? I know lots of backup cameras have a foil shield around the wires to keep from distorting the picture.

Shitty electronics emit radio interference, they’re just not built well, I lose all fm radio when I flip my (cheap) led cubes on. You’re talking about something like a faraday cage, you can’t really shield poor electronics and isolate them easily.

 

[bhaner]

I wonder if the relay is kicking on a GPS antenna or Satellite radio.

All that was disconnected and it was still causing noise.

 

[jeeeep]

Have you tried RFI filters?

usually one on the power line or coax seem to work

 

[bhaner]

Have you tried RFI filters?

usually one on the power line or coax seem to work

That is on my list of things to try.

 

[Colorado4x4]

I would try a filter. Do you have a backup camera? My backup camera caused me a bunch of issues with my ham setup when I had my antenna on the rear tailgate. I since moved the antenna up to the driver side hood area and don’t have any issues. I thought I wouldn’t like the hood antenna location because it’s in the way, but it seems to work better on the hood. And now my wife isn’t always whacking the antenna with the rear lift glass because she didn’t open the tailgate door all the way.

 

[bhaner]

I would try a filter. Do you have a backup camera? My backup camera caused me a bunch of issues with my ham setup when I had my antenna on the rear tailgate. I since moved the antenna up to the driver side hood area and don’t have any issues. I thought I wouldn’t like the hood antenna location because it’s in the way, but it seems to work better on the hood. And now my wife isn’t always whacking the antenna with the rear lift glass because she didn’t open the tailgate door all the way.

I think a filter is going to be worth a shot. Going to start with one for the antenna.

I have a backup camera so I will try disconnecting it and see what happens. I think I did that when I isolated the Maestro box... But not 100% sure where the camera feed power comes from.

 

[Colorado4x4]

I think a filter is going to be worth a shot. Going to start with one for the antenna.

I have a backup camera so I will try disconnecting it and see what happens. I think I did that when I isolated the Maestro box... But not 100% sure where the camera feed power comes from.

So I used to have my antenna on the rear tailgate. I recently installed a backup camera and ran the wire down the passenger side floor board where my antenna coax is. My backup camera is tapped into the rear cigarette lighter for power and the backup camera is always on with key on. This completely jacked up my radio with RF. I couldn’t make it out 100 yards so I know for certain if your backup camera has constant power there will be RF and your radio will be a piece of bullshit. After I moved my antenna up to the hood then all was well again. I have a feeling that my antenna works better up front because of the hood ground plane and I’ve made way longer contacts on simplex (90 miles in the mountains) than before when the antenna was on the rear tailgate

 

[bhaner]

Well... Good/bad news is the camera doesn't seem to be the problem. Unplugged it and the noise is still there.

It all seems to be coming from the Maestro box. Still trying to get a replacement for that.

I haven't been able to find a filter for the antenna yet. Anyone have a link?

 

[Colorado4x4]

Dang it. Ok, so when you have the Jeep turned off and the radio powered on, does it work normally?

HF/VHF Transceiver RFI/Noise Kits - Common Mode Noise Filter - Coax - Palomar Engineers®

BUY THESE KIT NOW TO SOLVE YOUR RFI/EMI NEEDS! CHOOSE KITS FOR SPECIFIC BRANDS OR USE THE GENERIC STANDARD AND DELUXE KITS FOR OTHER BRANDS. STANDARD KIT FOR SINGLE ANTENNA TRANSCEIVERS, DELUXE KIT FOR MULTI-ANTENNA TRANSCEIVERS.

palomar-engineers.com

I have these on my Kenwood TM-V71A. There are a bunch of filters out there.