GMRS/FRS/MURS (VHF/UHF) Interference?

2007 Tundra 4WD Base

I've got several UHF/VHF radios and I tested them recently in city to see how good they were after being programmed. I gave one to my buddy in his jeep (1999 Jeep TJ w soft top) and I took the other in my truck; he wasn't getting any interference at all, but I was getting heavy interference and static from my radio we mainly stayed on FRS channel 4. I figured it was from the trucks electronic systems, anyone know channels on UHF/VHF that don't get crazy static?

(radios work great while not in the truck)

Has anyone else been getting static in the UHF/VHF ranges? Or know any frequencies or channels that don't get interferance?

 

these are the radios (I have upgraded antennas on them - pictured below)

 

bump

 

did you try adjusting the squelch at all?

other than that, should be fine. maybe try switching the antennas back to stock too.

 

Have you switched radios to see if it stays with the radio or the car?

I bet an external antenna will work better if it is interference from inside the truck.

A UHF Mag Mount should do the trick and be really small too.

 

I’m thinking squelch too.

IME the stock squelch settings were far too low on Baofeng radios. You can program them with the CHIRP app using the settings found here https://www.miklor.com/COM/UV_Squelch.php

 

I set the squelch to 7, and even setting it to 9 doesn't help, I'll try switching back to stock antennas

 

I've been looking to the external mount as well, with them just on in my truck I've gotten slight static on FRS and GMRS frequencies, nothing on MURS. Really just needs to be tested with someone talking to me to get the same effect.

 

That’s why I said the squelch settings need to be reprogrammed.

 

I believe it did get reprogrammed when I got them tuned/programmed, the guy did say he set it higher than you could on the radio, but not too sure, I'm gonna end up purchasing the tuning cable myself

 

Assuming the 2nd gen/3rd gen interior potential-interference generators are similar, I can say I haven't had any interference issues in my truck.

I've used a number of different

$18 Baofeng UV-5R Dual Band Two Way Radio (Black), 144-148MHz & 420-450MHz

Baofeng UV-5R versions/revisions (I think I have 6-7 of them, 3 live in the truck usually, at least one in my gf's Tacoma as a back up for her, etc), with several antennas (I've gotten a few different "factory" antennas with my radios, as well as the 8 and 16" Nagoya antennas (in both amateur and commercial variants) and never experienced any Tx/Rx interference per se... (on VHF and UHF)

The only time I've noticed any issues is when using the 12v plug-in battery replacement on the radio; I've noticed it does weird things or creates a steady ground-loop like hum; and I've gone through a lot of remote speaker mics, it appears they all either show up bad or go bad with in a few hours of use.

I've also used Motorola hand held GMRS radios without any issues in the truck.

However, the normally used radio is an Icom 2730A dual band, and I've used that on VHF and UHF frequencies without any issues as well.

 

number one issue with interference is voltage, whether from aftermarket accessories or bad grounds, that is usually the issue when it come to stand alone radios. Usuallt someone wires their amp close by to a stereo or radio and cause and issue...

 

So the 'Feng are really not type accepted for use on FRS bands and aside from any legal conversation about operating them in this band I bet they also just are not really built to be operated there very well either?

I have literally NEVER has any 'Feng or related cheap radio perform well enough to use to transmit,not even once on almost any band without getting reports about it right away from others who are used to hearing me on Mainstream Japanese radios.

They are just crap in my experience and not worth the money no matter how cheap they sell for.

Buy once,Cry once like many other technical hobbies is my advice.

 

Agreed, I can only imagine that the step down built into that "battery adapter" is.. uhh... just as cheaply constructed as the Baofeng itself

This is also true... There is a reason I keep a few in the truck, because you never know when one (or more than one) may not want to work right; or you hit a bump wrong and whamo dead radio. Or, differently stated; why I use my mobile radio instead of the Baofengs

 

yesterday I used the radios on MURS 1 which is a VHF frequency for about 10 minutes in the city. My friend and I got ample distance apart and no random static interference. Maybe there is something or someone transmitting on UHF frequencies that's giving me so much trouble; more testing is needed, too many variables.

I'll probably end up getting one of those external mag mount antennas, and my programming cable is already on the way, thanks everyone for the input!

 

I have had 3 BF radios and never had any issues with them on the trails or in the desert, also have a TM281 in my truck and same, great comms. Granted cheap china radios have their limitations, but for the price, they work good if you know the basics.

In theory, UHF should actually do better in the city than VHF. A quick google search on the antenna model number shows lots of bad news, videos showing SWR of 2.0 (VHF) and other reviews claiming as high as 13.5 (UHF) which is AWFUL. You want the SWR to be as close to 1:1 as possible. You could probably make a more resonant antenna out of speaker wire than this thing based on reviews haha. Botttom line, try the stock antennas, make sure its broadband or you have the right one on for that freq. If you still have issues, very possibly could have damaged the radio if the antenna SWR was ridiculously high like that.

Lastly, its always good to find out who is using what freq's before just hopping on a channel. I have always used the link for two way comms and scanner searches: https://www.radioreference.com/apps/db/

 

I have several working radios (6), and they were probably treated pretty roughly by the previous owner, so I wouldn't be surprised if they are damaged internally (or just junk). I understand the SWR from tuning my CB antenna, so I get that, also to my knowledge if the antenna isn't right it will fry the radio/break it, so that could have happened. And when you say: "try the stock antennas, make sure its broadband or you have the right one on for that freq" do you mean make sure the aftermarket antennas are made for the UHF/VHF frequencies?

If I remember back in the past before they were programmed, I had always had random static and interference in just my truck, they had been used in a newer F-150, and '97 F-159, and '99 Jeep with no issues if I recall correctly from our exploration trips... I wouldn't be surprised with the truck being an 2007, Toyota did something different on their significant model change, but I'll continue to keep hunting, I'm looking into those magnetic mount antennas now

Also my buddy just bought two UV-S9s, so I'll test those as well and see how they work

 

OK I will say it again,just try getting the antenna outside of the metal cage and see if there is any difference?
Sit on the hood of you need to with the truck running maybe?
If it is better then get a cheap mag mount antenna and be done with it.

An antenna on an HT inside a vehicle is just not an optimal setup period.

 

What ezdog said is spot on too, try taking away the variable of the truck itself creating the issue.

Yes, so the general way an antenna works is the length of the antenna is equal to a specific length based on frequency (aka resonance). So for "broadband antennas" are a general length that works for a range of frequencies, say 144-440, but its actual resonant/optimal/peak freq is probably somewhere in the middle around 280 (just a figure). Cheap companies are gonna say they work for XXX-XXX freq but may not actually be efficient doing so. If you know you will be operating on VHF or UHF specifically, you might consider getting specific antennas for each to cut down on the chance of poor performing broadband antennas

 

Yeah thank you again, thats exactly what I plan on doing, just haven't picked out an antenna yet

 

For the most part using a HT inside of any vehicle is an extreme compromise at best. You're sitting in a metal box surround by glass (not to mention all the fancy electrical stuff in the truck doing what it does and causing RF noise) and expecting radios that can only do 2W max to work well. Even 5W GMRS under these circumstances isn't going to work much better but at least with GMRS you have the ability to have external antennas which will greatly help you with signal since it's not in that metal and glass box full of electrical interference anymore. You also have the option of running up to 50W with GMRS depending on the frequency. The other upside to GMRS is also interop with FRS .. yes you will have to use your callsign while your FRS buddies won't but the radios will talk to each other. They'll certainly hear you but you still might not hear them very well for the reasons mentioned earlier.

So in the end as others have mentioned ... get the antenna out of the car if possible. With GMRS this is possible with but FRS it is not due to FCC regulations. Also if you do get an external antenna get one tuned for the frequency range that radio can transmit on. Yes 70cm ham antennas will work with GMRS but it's above the frequency range they were designed to transmit on so they were never built to do it well. Receive is another story as most antennas will receive way outside of their TX frequencies. Get a GMRS specific antenna and you'll be good ... Midland has a few good options.

 

Yeah thats what I thought you were getting at, just picked out a external antenna so we'll see how it fares

 

yeah so it sounds like the first thing to do is get the antenna outside the truck, secondly test different channels on both UHF/VHF and see where I get interference, Eventually I'll probably get a in truck GMRS radio, but I already dished out the money for a whole CB setup right as everyone was switching to GMRS (and I have 6 UHF/VHF handhelds lying around) so just trying to get by without dropping even more money

 

You just can not beat the Physics though is the problem.