How to keep RF out of my other electronics?

Arctic Travelller

Adventurer
Greetings, I just installed a 2m /440 50w radio in my van. When I key up, it trips the protection circuit on my stereo. I've grounded the radio pretty well, have run new coax and all connectors are clean and tight. I've also heard RF can get into the vehicles computers causing problems. Anyone know how to prevent this? Thanks Arctic Traveller KC6TNI
 

KK6POV

Adventurer
Are you sure it is RF? Did you run a new line to battery with its own fuses?
Definitely run directly to your battery! I have never heard of that amount of RF damaging vehicle computers but anything is possible I suppose. I do know that your 2m is easily interfered with, especially by HID lights and other radios.
 

Arctic Travelller

Adventurer
Definitely run directly to your battery! I have never heard of that amount of RF damaging vehicle computers but anything is possible I suppose. I do know that your 2m is easily interfered with, especially by HID lights and other radios.

Oh great, I just installed HID's too. I have a #8 pair running from the Batt to a fuse block on the console that most electronics (except the stereo) are wired to. That's not to say that the battery voltage is not dropping, but I've never seen a radio go into protection mode from low voltage, they usually just shut down, this one doesn't.
 

Nomad1

Observer
Must really be some cheep electronics that do not have any shielding that they should have example like your radio...

But it sounds like he is taking off power from the stereo power line...
 

unseenone

Explorer
Does it trip the protection circuit on the radio when the vehicle is running?

You definitely want to run a separate power run direct from the battery as the other folks mentioned. You can run a temporary line and test it before installing it as well.

One of the best ways is to add a few turns of your coax outside the vehicle and install some ferrites. There is an example pictured, you see the turns and ferrite in the lower right hand corner. Follow this URL and you can click on the picture for a close up.

normal_20150531_115828-s.jpg


Here is a useful web site for ham technical installation stuff.
 
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Arctic Travelller

Adventurer
Does it trip the protection circuit on the radio when the vehicle is running?

You definitely want to run a separate power run direct from the battery as the other folks mentioned. You can run a temporary line and test it before installing it as well.

As I said, I did run seperate power directly from the battery. The first time the 2m radio tripped the protection circuit was when I started transmitting, prior to that it never tripped. Should the ferite be closer to the antenna, or would it be as effective near the radio? The reason I ask is there is little slack in the coax until I get near the radio, and pulling some of that slack back will be more work since I've got the cable pretty well anchored along the way. Thanks for the reply
 

unseenone

Explorer
OK, I just wanted to be clear. Did you put an SWR Meter on it, just for kicks?

As close to the base of the antenna as possible, outside the vehicle. What you are attempting to do here is to prevent RF from entering the cabin. You can certainly also install near the base of the radio as well, but near the antenna base outside the cabin is the idea.

See some pictures and explanation here. http://www.k0bg.com/rfi.html

You could also add to the DC feed lines, many Mobile radios have them already on the DC power cord. http://www.hamradio.com/detail.cfm?pid=H0-008867

You should be able to find them at a ham shop or a communications company perhaps in your area. You might also consider reaching out to a local ham club to get some help sorting it out. http://www.juneauamateurradioclub.com/ It looks like this is the contact email address.
 
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Chris Boyd

Explorer
x2 on the SWR meter on the antenna to see if the SWR is good. While you're at it tune it for resonance of the bands. I've seen many issues caused by a bad RF connector, causing RF to leak back thru the radio. Also ensure you have proper Antenna separation from the ham to the vehicle antenna. Have also seen RF coupling cause similar issue.
 

RLM975

Wannabe Oberlander
I've run a separate 60 amp buss for aftermarket accessories (including a 2M/70CM mobile and CB). Other than connecting to the battery and having a ground buss, the chassis electronics are not touched. I haven't had any RF problems, in either direction, ie alternator whine on audio, or radio interfering with chassis systems.
 

Arctic Travelller

Adventurer
I don't have an SWR mtr handy, but signal reports are great. My next move will be chokes, thanks. Thanks too for the great links, I spent a couple hours geting deep into them, and discovered some cool stuff I wasn't aware of, including a great battery monitor. http://www.westmountainradio.com/product_info.php?products_id=pwrcheck

I have the one that came with my solar controller, but it sucks and doesn't display current or wattage consumed. I'm getting ready for a long trip, so solving this RF issue is not at the top of the punch list, but I'm sure I'll give it some time before departing. Thanks again.
 

unseenone

Explorer
Great.. Ah.. What kind of solar controller do you have. MPPT will not be a problem on VHF/UHF but you can get some significant interference on HF with them. WMR and powerwerx are both great sites. The same rigrunners for example are cheaper on powerwerx.

Be sure and post back your progress and any other questions. Have a safe trip.
 

Arctic Travelller

Adventurer
Great.. Ah.. What kind of solar controller do you have. MPPT will not be a problem on VHF/UHF but you can get some significant interference on HF with them.

Yup, I've got the MPPT controller, but no HF rig yet. I"m saving that for the big trip in a couple years. I plan to drive from B.C. to Newfoundland, via dirt roads. [URL="http:/graveltravel.ca/] At that time, I expect to have an HF rig, so I guess I'll have to deal with the interference then. Any ideas on that front? Thanks............
 

unseenone

Explorer
I think it is virtually impossible from what I have figured to eliminate it. It can be quite annoying if you are trying to operate while charging. You can shut off the controller though and eliminate the interference. What I would recommend, seeing as you have time is something like the Morningstar PS-30-M PWM controller. You will not have any problems with something like that.

Don't get me wrong on the mppt controller, I do have one, that's how I know. Mine is a Morningstar MPPT-45, it's very nice, but even interferes with the Ham in my truck when in close proximity, so will other peoples solar installations, lucky for you it shouldn't be a problem where you are heading.

That sounds like a fun fun trip. I'm sure various folks from the board will meet you along the way. Fun stuff. I haven't heard of that web site before, you might mention it elsewhere as well, nice stuff. http:/graveltravel.ca
 

Arctic Travelller

Adventurer
That sounds like a fun fun trip. I'm sure various folks from the board will meet you along the way. Fun stuff. I haven't heard of that web site before, you might mention it elsewhere as well, nice stuff. http:/graveltravel.ca[/QUOTE]

I found his website becauswe he was a ride along with Rallypanam on a Paris Dakar race and wrote a book about the experience (sold on his site) I've got a couple more years to go before I can take an entire summer off, so until then I'll have to travel in the winter, probably not the best time to cross Canada.
 

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