So I am having a little issue with interference with my Ham radio(s). I have good ground on the antenna. I only get the interference after about 5 to 10 minutes of driving and its almost a constant static. I only get it on 146.46 that i have found so far. I also get the static on baofeng portable radio same channel, if i put the baofeng radio on the visor and turn the antenna away from the jeep the static goes away. but if i put the palm of my hand touching the metal of the shift lever the static is constant and i can play with the noise by touching, not touching, touching, not touching. I know i have good ground on the antenna for the base unit. I don't think running a ferret choke would do anything with this issue cause i believe its just the antenna getting interference on a certain frequency. maybe static electricity from the transmission? maybe running a ground strap to the transmission from the frame? or maybe an anti-static strap? i'm open to any ideas or suggestions. for the short term I've just been using alternative channels to avoid the noise. Thank you for your help.
Discussion
Hello I got my technician license. I primarily got my license to use 5 watt baofengs for off road and over landing purposes, though I do have a mobile unit in my jeep that is uhf/vhf 50 watt that I use when I am on the go and much prefer the strong radio and large antenna over the little Baofengs. now I don't think I will ever convince friends/family to commit to that kind of investment into a more powerful radio that is more intrusive in your vehicle. especially since the Baofengs are so convenient and are far superior to CB radio in every way imaginable, in my opinion. Now the advice I am in need of is that I have a dream of turning my jeep into a repeater for friends and family to use when we are out on the trail, as we are regularly outside of cell phone reception, and once we set up camp you would be able to use the jeeps much larger antenna and 40 watt power source to send your baofeng signal significantly further and if some one decided to go hiking it would be a much more reliable and reach further then the simple baofengs by themselves. what i have come up with thus far is either getting a radio that performs the function by itself https://www.amazon.com/gp/product/B014R3FGWW/ref=ox_sc_saved_title_4?smid=A3EB62EZDL1WQ0&psc=1
OR https://www.amazon.com/gp/product/B071F9FDVV/ref=ox_sc_saved_title_3?smid=A25505C8NUXJM5&psc=1
or alternatively, using this device which seems to be just a repeater in a box that i could then just use an amplifier between this and the antenna https://www.amazon.com/gp/product/B07PKQD7BZ/ref=ox_sc_saved_title_5?smid=AJFR970E0U757&psc=1
now i am not sure if i am even on the right track of coming up with a feasible solution or if i'm just wasting my time all together. I also have had trouble coming up with antenna solutions as well. originally i planned on using a 102" stainless steel whip antenna but have recently learned that that isn't even close to the correct antenna to use. but i would like to get a long antenna that could be pulled over to avoid getting hit by branches and then deployed when i need it. the antenna only needs to be for VHF not dual band. Thank you for your time any advice is greatly appreciated, Figgins KJ7JVE
Maybe some guidance can be found here
https://hamradioschool.com/going-mobile-part-2-solving-rfi-problems/
It does sound like a grounding problem
The transmission is already well grounded by its connection to the chassis.
is that a question? i know we talked about this already and i checked my grounds and they are very strong. but even if they were not. it wouldn't effect the handheld would it? and the fact that it builds up over time and not right away. actually my dad and i were talking and he thinks it might be interference from an electric fan. which makes sense. cause this jeep is fan crazy when it wants to be. question is, what would i do about that?
@Michael Figgins your original post mentioned grounding the transmission to the frame. I was just pointing out that it already is. An electric fan seems like it should only cause intermittent issue since it shouldn't run full time. Perhaps a ferrite choke on the radio's power lead?
@Aaron Kravik well the jeep JL fans are obnoxious and do whatever they want. including full jet engine mode at the smallest hint of over heating. it is possible that they are being triggered during normal operations once the jeep warms up to normal temp to keep it from going to high. and i see what you are saying about the transmission ground now. that would have been my assumption as well. i read it wrong the first time. i don't think it would hurt to throw a ferrite choke on the base units lead. but why would that effect the handheld radio? and i have run the handheld without the base unit off and gotten the same static. so it cant just be the power lead can it? i read the article John Russell posted and the only thing that seems to make sense is maybe the exhaust system and the hood need better grounding? it is obviously the vehicle causing the problem, just need to figure out what
Does the noise vary with engine speed? Injectors are known to be rf noisy. Also strange that you seem to only get it at one frequency. Does squelch hide it?
No resolution but a similar problem in this thread. LED taillights?
https://www.jlwranglerforums.com/forum/threads/cb-picking-up-interference.22379/
It doesnt make a difference what speed the engine is. and the last 2 days i've been playing with it on my commute and it has become more more sporadic than before. and as i pulled into the driveway today and parked pressing the brake lights was making it do it. but i do not have LED tail lights.
@John Russell good find on that forum Fyr196 is for sure having the same issue as me just on a different channel. i think its almost time to just buy a 20 pack of ground straps and just go crazy with them
What modifications have you made to the vehicle? What has been added? (Dash cam, lights, switch modules, etc.)
i have a dash cam but it isn't in the jeep right now.
cb but it isn't plugged in to power right now
Arb twin compressor under the hood not wired through the firewall
6 overhead offroad lights wired through the dash
2 front offroad lights but not wired through the dash
i think that is it for electrical. I've played with them toggling them off and on and neither seem to make a difference to the static
Even though the tails aren't LED, they probably still use a PWM signal to drive them. Modern vehicles are getting pretty dirty as far as RF goes. They shield for what would be considered important frequencies (i.e. mobile phones, WiFi, etc., typically higher Ghz ranges, although T-Mo is now using ~700Mhz for 4G), but beyond that its a radiation fest. You might just have to add the ground straps everywhere you can and see if that helps. The handheld picking it up implies its a noise being generated as opposed to an installation or antenna problem. You may check the antenna cable though, its possible the cable has a flaw or crimped shield that exacerbates the problem.
I had a fascinating development today. last night i pulled the antenna to test a couple of symptoms to get more information about what might be causing it. did not learn anything new. but when i put the antenna back on i put it on significantly tighter (not thread breaking tight but tighter then it was) because i didnt plan on taking it off again anytime soon (since my next step was to start deploying ground straps) and i cannot get the interference to come back. i'm not yet 100% convinced that problem is "SOLVED". but i didn't get one blip of interference in an hour long commute. suffice to say that i didn't use the handheld at all to test, and didn't go around channel skipping or anything. So I either fixed the antenna or broke it. lol