Monitoring FRS/GMRS Traffic With A UV-5R

Guide Nov 25, 2020

At the end of my guide on using the UV-5R as a cheap conventional scanner I mentioned that I had programmed the FRS/GMRS frequencies into it but didn't go super deep into them. Since I've seen a bunch of photos from protests with individuals wearing various types of radios I decided to go into a bit more detail on what they are and how to monitor them.

First some definitions courtesy of the FCC.

The Family Radio Service (FRS) is a private, two-way, short-distance voice and data communications service for facilitating family and group activities. The most common use for FRS channels is short-distance, two-way voice communications using small hand-held radios that are similar to walkie-talkies.

The FRS is authorized 22 channels in the 462 MHz and 467 MHz range, all of which are shared with GMRS.

GMRS stands for General Mobile Radio Service and while it shares frequencies with FRS you get some more fiddly bits like being able to use a higher transmit power as well as "short data messaging applications including text messaging and GPS location information.". However you are required to have a license which will put you back 70 bucks.

Basically these are frequencies that you use when you buy a walkie talkie from a big box store. Though on those walkie talkies you'll usually just see the channels and not the frequencies.

One final things before we get into programming and this is a big one.

Using a Part 90 device (ie a Baofeng UV-5R or one of it's siblings) it's technically illegal to broadcast on the FRS/GMRS frequencies. From my research I haven't found any instances of the FCC actually enforcing this but it's something to be aware of.

To be legal you'll need to have a Part 95 certified radio like the Baofeng GMRS-V1 or any of the various off the shelf solutions. There is also some other things like channel bandwidth you're allowed to use without a license but since you shouldn't be transmitting on a UV-5R I'm not going to get into it.

Much like before we're going to be using CHIRP to program the UV-5R with these frequencies. Follow my previous guide or this guide to get your radio image loaded into CHIRP. It will look something like this.

Now select all and wipe it! From here you'll want to go to File -> Open Stock Config -> US FRS and GMRS Channels.

It'll look something like this when it's opened.

From here you can select the channels FRS 1-22, copy them and then paste into your UV-5R image file. Don't worry about the Tune Step column as that doesn't matter for the UV-5r.

You've probably noticed that there are also frequencies labeled GMRS 1-22. Technically you don't have to copy these in as they're the same frequencies but the channel bandwidth is different for fifteen of the GMRS channels. Based on my testing this doesn't actually change what you'll hear* but if you want to be 100% sure you'll hear everything you can paste them in too.

*At least on the UV-5R. My Radioditty GD-77 got a little unhappy and started broadcasting static through the speaker when I futzed with the bandwidth.

When all is said and done you'll have something that looks like this.

I would recommend changing all Power fields to Low just in case you accidentally transmit you aren't in violation of the power limits of FRS. Though since you shouldn't be transmitting anyway I would just turn off VHF/UHF TX in the Other Settings Menu.

Also these are all simplex channels so don't worry about the Duplex field, that can stay at none. If you want to futz around with radio settings I would refer to my other guide linked at the top of this one.

Finally save your img file, plug in your radio and upload it. Then press VFO/MR on the radio and you’ll be on the favorites list with A and B. You can start scanning by holding down *.

In this case the A and B doesn't matter very much for scanning but may be useful if you want to monitor two frequencies that you've found with traffic on them.

You may be asking yourself why I didn't have you program any tones in.

Well for monitoring purposes they don't matter at all. You can hear all transmissions on a frequency with your tone set to None/CSQ even if the transmitting party is using a tone or "privacy code". They provide absolutely zero privacy and only serve to allow multiple users to use the same frequency.

You can "capture" the tone being used if you really want to know but it's a rather convoluted process on the UV-5R, more info on that here. If you want to see what codes correspond to what tones there's a table here.

The only way you're getting privacy on a radio is with encryption and that's not happening here.

To sum up: anybody can hear anything transmitted on FRS/GMRS (or any unencrypted frequency for that matter).

Now that you've got your UV-5R programmed with the FRS/GMRS frequencies you're probably wondering what you're going to hear and how far away you can hear it. The answer to that is entirely dependent on where you are, the type of antenna you have and what type of radios are being used.

For example if you're at a protest in an urban setting you're going to likely hear anybody using an FRS/GMRS capable radio within a few blocks of you though it depends on their transmit power.

Per the FCC:

The usual range of an FRS device on channels 8-14 is less than one-half mile, but longer range communications can be achieve on channels 1-7 and 15-22 depending on conditions

As to what you'll hear that's entirely dependent on the types of people using the radios assuming anybody is. When testing out one of my antennas the most interesting thing I heard was some kids talking to each other from their houses. Your mileage may vary.

A quick note about GMRS. If someone is transmitting on a GMRS capable radio and using a higher transmit power their transmission will likely go farther (see this article for a lot of words on GMRS range). However they also have to transmit their callsign at the beginning/end of each transmission and at least every 10 minutes. Each callsign is unique and tied to a specific person.

So if you are GMRS licensed and using a GMRS capable radio don't forget to transmit your callsign!

Now it is possible that someone with a UV-5R is not using the FRS/GMRS frequencies. They could be using MURS or the 2 meter/70 centimeter amateur radio bands if they're licensed.

MURS is pretty easy to program and can be found under the US MURS Channels in the File -> Open Stock Config menu. The National Calling Frequencies (Ham Simplex) for 2 meter and 70 centimeter can also be found there.

Technically per the ARRL band plans anything between 146.40-146.58 MHz and 147.42-147.57 MHz are considered simplex. If you're feeling feisty you could look up your local radio club band plans and program in their simplex frequencies as well. With that being said it's unlikely these frequencies will be used by non licensed individuals.

And with all of that you're set to monitor the FRS/GMRS frequencies using a UV-5R or other CHIRP compatible radio. Watch this space for a link to the img file with all the frequencies for easy loading onto your UV-5R.

If there is any interest I'll do a writeup for monitoring FRS/GRMS with a Radioditty GD-77 as that's the other radio I own. You can also plug these frequencies into commercial scanners and the Uniden models come with them preloaded as searches.

Leave a comment if you have any questions!

I suppose you could accomplish almost the exact same thing by buying some walkie-talkies from a store but where's the fun in that?

Ethan H

System Administrator turned Security Analyst. Enjoys following digital breadcrumb trails to their source and have an interest in threat hunting and incident response as it pertains to the Cloud.

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