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Hey folks. I have had a small group of people ask me about tones and GMRS/FRS basics in the past week. I figured I would take one of the conversations here and share it for people new to the service. Hopefully it will help you understand Private Lines, Privacy Tones, sub-channels, tones and squelching methods, in general. I am only covering the two most popular in GMRS and FRS, but there are many others available as you move into different radio services and technology. Before we get into what all that stuff is, lets talk about why it exists. Per NOAA and the US Census Bureau, the lower 48 states is approximately 3.1 million square miles. Also, 83% of Americans live on 10% of the total available square miles and 40% of all US citizens live on the east and west coast in counties touching oceans. Following this logic, about 500,000+ licensed and unlicensed operators (estimated by me) are sharing FRS and GMRS radio space, in roughly 310,000 square miles. So, how does 500,000 people in close proximity, sharing 22 channels, all use their radios at the same time without interfering with each other? Motorola brings you PL tones! Lets get this out of the way... regardless of what the manufacturers may tell you or how they label their products, there is no privacy. Period. Private Lines (PL), Privacy Tones, Sub-channels and any other name for the same service, does not stop people from hearing you, it stops you from hearing them. I know... seems like a day in Opposite World, but that's how it works. I suppose the first thing to do is explain what the PL tones really are, what the more common types are and what each of them do. A traditional squelch is a signal level squelch. Meaning, no audio will come out of the speaker until a strong enough signal is received. Then there are also user squelch types. With analog radios, the most common type of user squelch uses encoding called Continuous Tone-Coded Squelch System or CTCSS. This feature is defined as being used to reduce the annoyance of listening to other users on a shared two-way radio channel. So, as mentioned above, its not that you as a person speaking have any type of privacy, but rather you don't have to listen to everyone on the same frequency. Hopefully the third time is a charm. Many GMRS and FRS radios only have simple CTCSS functions called Tone Squelch, often displayed as TSQL on the screen when enabled. This means two things. One is, regardless of what you do with your squelch knob or set your RF squelch to, no audio will come out of the speaker unless the tone you selected is embedded in the signal you are receiving. The other thing it does is, when you transmit, what ever tone frequency you have programed gets transmitted with/in your signal to unlock or open the squelch of other radios configured the same way. There is another method of CTCSS called "split tone". This means that you can use one tone when you transmit and another for your receive. This comes in handy when repeater owners are trying to limit who can access the repeater, as higher cost radios typically have split tone capability, compared to poorly built and inexpensive radios that would be problematic on a repeater do not. Also, this makes it a bit more difficult to "discover" the input tone by using scanning tools. Another function of split tone CTCSS is that you can also set your radio to transmit a tone to unlock a repeater or other radio, but leave your receive tone set to null (nothing). When this mode is enabled, there is typically a display on the radio that either reads TN or TONE. That means you can bring up a repeater or unlock a radio squelch, but also hear everyone else regardless of what tones they are running, if any at all. This is actually a great feature for GMRS radios since Repeater Channels share FRS frequencies and GMRS simplex frequencies. So you can tell if the frequency is in use as well as being able to talk to others who many not be using the repeater. CTCSS is an analog squelching system. There is also a digital squelching system called Digital-Code Squelch or DCS. It has similar use cases as CTCSS, but it is sending digitally embedded numeric codes instead of a sub-audible tone. I apologize in advance, but this next portion may get a little confusing. If you have questions, just ask and myself or one of the other knowledgeable members will be able to help. All of the numbers below are simply random samples I selected for example. Last I checked, there are 38 standard tones and an additional 13 expanded tones (not available on every radio) for a total possible 51 tones and 83 DCS codes. Along with the use examples above, you can get creative with DCS, because we are dealing with binary numbers instead of a tone. You can have the numbers used in a bunch of different combinations. For example, the number 411 in binary is 00110100 00110001 00110001. The reverse of this would be 11001011 11001011 11001110. So we are swapping the meaning of a 1 and a 0. So the combinations could be as follows: Normal-Normal = Transmit sends 411 and your radio squelch only opens when it receives 411 in the standard format 00110100 00110001 00110001. Reverse-Reverse = Transmit sends 411 reversed (or bit swapped) and your radio squelch only opens when it receives 411 reversed, meaning 11001011 11001011 11001110. Normal-Reverse = Transmit sends 411 standard binary format and your radio squelch only opens when it receives 411 in a reversed binary format. Reverse-Normal = Transmit sends 411 in a reversed binary format and your radio squelch only opens when it receives 411 in a standard format. Unfortunately, I am unaware of any radio's that have a DCS option to leave your user squelch open while transmitting a DCS code. If DCS is enabled, you cannot hear anyone else unless they are using the same DCS number and binary combination. CTCSS tones can also be "reversed". CTCSS tones, since its analog, we have a phase reversal, often called "reverse burst" when it is only reversed at the end of the transmission. (Something to Google in your spare time.) On some high-end radios, squelching can get really exotic. You may be able to create your own custom tone instead of using one of the standard tones. You may also be able to combine CTCSS tones and DCS codes. For example: User-CTCSS = Transmit 2600Hz tone, squelch opens with 2600Hz tone. (random number example) T-DCS = Transmit 141.3 tone, squelch opens with 411 code. DCS-T = Transmit 411 code, squelch opens with 141.3 tone. T-rDCS = Transmit 141.3 tone, squelch opens with 411 bit swapped code. rDCS-T = Transmit 411 bit swapped code, squelch opens with 141.3 tone. Now, here is the kind of disappointing part. Some manufactures try to make their equipment sound like something its not. They will use things like there own custom number code to identify a traditional CTCSS code. For example, Midland uses code number 22 (also known as a sub-channel) to indicate the tone 141.3. This makes coordination on tone selection a bit cumbersome between some brands. It also means that if your radio doesn't display the actual CTCSS tone or DCS code, you need to keep your owner's manual handy for reference. So... I don't know if that explanation made things better or worse. LOL Anyway, some companies use verbiage like "Privacy Tones" which adds to the confusion for some people. If you are using a true full CTCSS, it just means you are limited to whom you can hear, but everyone can still hear you. The examples I provided above for DCS are not what actually gets transmitted, but rather a conceptual process to help understand at a very basic level of what occurs, simply to understand the difference. DCS adds a 134.4 bps bitstream to the transmitted audio. To move past concept to the weeds, this video does a great job.

Hey folks, I am leaving for vacation in a couple of hours and don't have time for a proper test... but I wanted to let you all know that I got the radio back from Midland and I can't be happier. With a quick bench test using low pressure alligator clip test wires for the power supply, I am now getting 48w of output power on both the 462MHz and 467MHz frequencies! I'm sure with a proper power cable, it will be perfect. Once I get home and have a chance to do some proper testing for output power and 12dB SINAD receiver sensitivity test, I'll share the results.

I own and have used every one of those radios... All are great radios - Except for the 50X1 - Scratch that one off your list. Its overpriced and VERY limited in its features and in my OPINION, it is not worth the price - and you will never actually get 50W out of it. The XS20G is a great (very) little radio. The UV9G Pro is a great radio - but also very complicated.. Same with the 916 (I have one, it will be a long time before you can get one)- But if all the pre-programmed SHTF stuff is what you want/need, then either is a great choice.. I would recommend also considering the KG-905G OR the KG-935G. The 905G is SUPER simple.. the 935G is a little more complex/does a little more, but IMO, still easier than the UV9G or 916.

So, one of the things to look for in a radio, is one that has a LED/Light that illuminates when the frequency is being used, regardless of whether the party transmitting is using a squelch code and regardless if your radio requires a code to un-squelch. Of all the radios I own, only the cheap Midland radios do not have the frequency-in-use light. That light prevents the need to manually open squelch to check to see if the frequency is in use. The light tells you it is busy. Good job Marc. Michael WRHS965 KE8PLM

Welcome to the forum! But watch out for "some people" that will try to grossly over-complicate things when answering even the most simple of questions in sad attempts to show you how smart they think they are. Superhet receivers are generally "better" than cheap SOC type radios - but most people would not notice any difference.. I would worry more about features/what the radio can do more than the receiver type, but thats just me. On wattage, unless you are looking at a huge difference like 25W vs 5W, you aren't going to see much difference in range - for example, the only thing you would notice on an 8W radio vs a 5W radio, is that the battery will go dead faster on the 8W. For the antenna, almost anything will work better than the rubber ducky on your 5Gs. You didnt say if you wanted to upgrade to another HT or a base/mobile type radio - if you post what you're considering we can give some feedback on the exact model.

My radio lights up white when I am receiving a signal that does not open the squelch due to a different tone.

Put another way: You receive a transmission on a specific channel and their tone opens your squelch so you can hear them. Now another transmission within your reception zone on that channel commences on a different tone. It does not matter that it is a different tone: your squelch is already open and both signals will be received and their distance and transmission power will cause the FM Capture Effect to determine which signal overpowers the other, or, alternatively, causes unintelligible communication between both signals.

Do you have a programming cable and the necessary software for programming the repeater? Assuming you have a suitable computer and the aforementioned software and cable, the programming of the repeater is pretty simple. The CE-27 software is needed, but I used the -d switch for the executable to allow it to enter "dealer" mode. In my case, the executable file is CE27Win.exe, so I ran it as "CE27Win.exe -d" to access the dealer mode. I believe this was required to allow me to set the repeater to wide band. It's probably obvious that since the executable file is an exe extension, it is intended to run on Windows. I actually use mine in Linux with WINE set up for Windows compatibility. The next thing you'll want to do is to read the programming from the repeater and then save the original file. Immediately rename the file to something else so the original file does not become corrupted. I usually include the date that I saved the file in the file name so I can see when the file was created. Once you've renamed the file, you can edit the table to enter the values you want to use. You have 16 channels to choose from, and can add CTCSS and/or DCS codes for the transmit and receive frequencies, adjust power levels, set wide/narrow options and simplex/duplex options, among other things as desired. Once you have it set as desired, save it again, then write it to the repeater. Here's how I have mine programmed currently: I am using a duplexer tuned to the 462.625/467.625 frequency pair, so as you can see, most of the channels are programmed for that pair's Tx and Rx frequencies. I did this to give me a lot of options for tones and power settings. Channels 15 and 16 are one step above or below, just in case I need to set the repeater to a different frequency pair which should work okay with the duplexer. The first eight channels are set for either high or low power for each of four CTCSS decoder (receive) codes. If desired, encoder codes can also be set, but mine are set to "off" (no code used). Channels 9-12 use DCS for decoder codes instead of CTCSS, and again are programmed for high and low power for each of the DCS codes used. The CW-ID option is set for all channels because I've programmed my call sign into the repeater and set it to ID every 15 minutes. This can be configured in the CW-ID section of the "common" menu. I don't recall whether or not I changed any of the other settings, but the settings shown are working for me. I hope this helps.

So, no mag mount, no lip mount, and you don't want to drill holes. Have to be honest, i have no idea what else you could possibly do except use your handheld. I mean, you are asking how to mount an antenna without mounting an antenna... so holding it is all that is left. What kind of vehicle is it? I mean, I put a lip mount on a $100k Challenger Hellcat that was even painted black and had zero issue with the paint. That really is the best method if you want it to work and not have damage.

This whole thread is his fault. I was studying for my Technician license and didn't know GMRS even existed till I saw his videos. After watching his videos I want to GMRS and Ham.

Ditto. The only way I was thinking a lip mount was if there was a convenient existing bolt to use.

@mbrun I love that feature. Some of my radios also light different colors, depending on if the signal is analog or digital

I have this problem with both fire and private security personnel, people that carry a radio as part of their job everyday as well. Yesterday, I had to have a firefighter show an office worker how to find the serial number on her APX8000 Motorola radio. I was attempting to confirm the serial number to a radio ID. This was commercial and very expensive radio, and this type of situation still takes place. But, you are ahead of many that do not even place a label on the radio or attempt to instruct end users.

Do you have a screenshot of what kind of adjustments are available?

I would assume an EdFong antenna means some sort of base radio. Superheterodyne can be poorly designed too, just be aware of that. My recommendation for radio goes for the Vertex Standard VX-4207, which will not intermod, nor desense, and its part 95. @wayovertherehas experience using that radio. For antenna I would go with this: https://www.ebay.com/itm/133810193897?epid=1941709490&hash=item1f27b585e9:g:Y5EAAOSwLCdgUyaI, which you can later upgrade to a 2-bay or 4-bay configuration for increased gain. G.

I know this is an old topic, but perhaps someone might be still interested in it…. obviously no bubble pack FRS HT is going to be repeater compatible, by definition. But as a GMRS license covers the whole family, I can see where non-tech family members would like an easy to use radio that is still repeater capable. When I faced that issue, I bought a couple of Retevis RB26s. Before we go someplace I program it with any relevant repeaters, and then I put a label on the radio listing whatever channels we are going to be using. The RB26s have no screen, you just push a button and a voice tells you what channel you’re in. Then I tell the user “keep it on channel 16. If you can’t get in touch with me, try channel 26” (just an example). The user doesn’t even have to know what a repeater is, they can still utilize it. (I also have our call sign and proper radio etiquette on a card taped to the radio. I go over it with everyone, and practice it, but they tend to forget.)

Vertex Standard VX-4207.

Repeaters are opposite of general programming, the TX frequency of a radio is the RX frequency of the repeater, and the RX frequency of the radio is the TX frequency of the repeater, for GMRS that mean repeaters listen on 467, and transmit of 462. In other radio services, the TX could be above or below the RX frequency, but it's laid only one way in the GMRS regs.

You mobile or HT radio transmits on the 467 frequency and receives on the 462 frequency. That means the repeater has to RECEIVE (from your HT or mobile) on 467 and TRANSMIT (back to your HT or mobile) on 462. So the high side of the duplexer goes to receive, and low side to transmit.

No Worries! (Not like you're the only one and, well it's text not voice)

? My apologies...corrected my post above as well. Hard to get a feel from a call sign, but I shouldn't assume. Agreed, the btech isnt the value proposition it used to be. Also agreed on advocating for following the rules, I'll provide the information i can to help people make informed choices...from there, we're all adults and can decide which way we go..I stick with part 95 equipment as well. On the part 90 market, part 90 in itself isn't strictly approved, but there are some out there certified for both (90/95a). It's not as easy as grabbing one of the off the shelf radio, the fcc id is key here to check to be sure. Kenwood and Motorola have a few, though I'm not as familiar with model numbers as some other members. Mine is a Vertex Standard, and it's the one model of theirs I've found that had 95a certification. Fcc id is K6610354640 (link to the grant)

For most radio services that are 'shared frequency' the rule is monitor before transmitting. (although I doubt anyone actively does this anymore, rule or no rule) On a lot of commercial systems, at least in years past, the microphone hanger would enable a RX coded squelch when hung up, but would be carrier squelch receive when the microphone was removed from the hanger. Most portables have a monitor button which, when pressed, likewise disables the receiver's coded squelch. I think the 'big lie' by many manufacturers, is using the term 'privacy'. Even with CTCSS or DCS, other people can still hear what you are saying and, where GMRS is concerned, the only 'privacy' would be encryption, which is not allowed under the rules. This, encryption, was (apparently) once allowed as my other half has a pair of old Radio Shack 'bubble pack' FRS portables that do have encryption! I discovered this when checking the radio out one day on a service monitor. The point is, and marcspaz did a great job of explaining it, there are sub-audio coding options, CTCSS and DCS (also various forms of paging and select call), to keep your radio silent except for who you want to hear. This again, is NOT 'privacy'.

All great info to add! Thank you both!

Depending if you have a passanger, you could do something like this: https://www.arcantenna.com/products/trab4500np-m2m-400-490-mhz-black-low-profile-omni-antenna Mount it in the rear window behind the passenger seat (2'8" from you for RF exposure requirements at 20W), could make a bracket off the seat bolt. There really aren't many options, other than to find a window lip mount and roll the window up on it.

Marc’s explanation is absolutely excellent and should be pinned. I learned from it. I would just propose one addition and I apologize to Marc if it’s pedantic. Privacy tones do not prevent interference. If two nearby groups are on the same frequency, but different tones, and one person from each group transmits at the same time, a receiver with receive tones set will lock in on the stronger signal, regardless of tone. It just won’t reproduce the audio if the tone sent with the stronger signal is incorrect. This could mean that your receiver remains squelched, causing you to miss a transmission that you were intended to receive. Another thing to consider is that having receive tones set prevents you from hearing a conversation on the same frequency before you transmit over the top of them.

Such empty.... ?

Stico makes disguised antennas that mount underneath the molded bumper covers (either front or rear). I've also done stuff for UHF where we just formed an angle bracket that used the license plate mount, and then ran a standard NMO off that. Works if the plate isn't recessed very far. Doesn't get the antenna up, but gets it out... Just looking at the car, I'd be tempted to buy a replacement passenger side mirror, fab a mount for an NMO with a 6" hatpin into that mirror with some copper sheathing molded to the underside behind the mirror assembly for a ground plane - then run the coax down into the door and through the existing loom into the dash. Call it a day. Easy to return to stock when it's time, and should work well.

On my F150, I used a metal plate for a mag mount. I used the 3M VHB tape. No issues even at highway speeds. https://www.amazon.com/Double-Mounting-Waterproof-Outdoor-Black，1/dp/B08T1HB5LJ/ref=sr_1_3?crid=2JGJN3D63QVAG&keywords=3M+VHB+Tape&qid=1644586028&s=office-products&sprefix=3m+vhb+tape%2Coffice-products%2C65&sr=1-3

I ran this antenna for many years in a few specific vehicles. Its rated for 35 watts and works well as long as its in site. Don't stuff behind trim. Just 3M tape to the rear glass. https://www.amazon.com/Covert-SB450FME12-450-470mhz-Internal-Antenna/dp/B007JSDDFA Mine was from Laird I think but doesn't come up on there site ant longer. Heck I may still have one in the parts box out in the barn. They made one for 800 that we used alot for volunteer fire chiefs when we were 800mhz. I would think this would work well for your application.

Nice!!! If I HAVE to put an antenna on that car I would fabricate a bracket that would bolt to the cowl underneath the front lid on the passenger side and use an NMO mount using existing bolts that are going into metal for grounding. That might be a problem as that care is most likely composite, but you can run a ground to the bracket if needed.. The mount can be sheet metal with the proper bends that would attach to the nearest bolts. Once fabricated I would have it dipped in black vinyl and add rubber bumpers for added safety to prevent any contact with painted surfaces or areas that can be seen. Run cable the traditional way through the firewall. The best thing about doing it this way is you can unscrew the antenna when not in use and put on an black NMO cap, which would blend in and nobody would even notice. That would be my approach, but I would need to see underneath the hood to make a template. Doing it this way is you can pull everything out in less than 20-minutes and restore the car back to original. No holes, no scratches. Using the NMO mount will give you a better choice of antennas, especially black ones. A black Larsen 1/4 wave antenna won't even be seen from a distance. Just be aware of the windshield wiper operation and factor that into you measurements. Here's a black 1/4 wave NMO. https://www.amazon.com/Laird-Technologies-450-470-Quarterwave-Antenna/dp/B0079555WM/ref=pd_lpo_1?pd_rd_i=B0079555WM&psc=1

Nice ride!! Fiberglass is even worse than aluminum, at least aluminum is metal... G. EDIT: Hope you are using Motorola APX radios in that ride... no excuse to buy a CCR... LOL

If you want just for temporary use when your car club gets together, what about a suction mount? https://www.amazon.com/Rugged-Radios-NMO-SC-Suction-Antenna/dp/B08177PQPH

Found a 20w... https://www.retevis.com/high-gain-antenna-rhd-701-sma-female-dual-band#C9045AX1

Yes, the mount an associated cable will support a 20w system. The question is, will the antenna you buy support a 20w system. That mount comes in options for antenna compatibility. BNC, SMA and reverse SMA. I would find an antenna you like and buy the corresponding mount. All of the types it supports are handheld antennas. So I wouldn't expect much in the power department. Max is typically 10w. Example: https://www.buytwowayradios.com/nagoya-na-771g.html

Cool! I understand the problem, I'm currently considering options of mounting antenna on BMW i3, which is fully plastic. Should it be my car, I'd drilled it, but it's not my car. Right now I'm torn between sticky plate on the roof or rear spoiler, fabricated mounting bracket that will be held by hinge bolts of the rear hatch (preferred option so far), or slot antenna inside the rear spoiler (full stealth install and an engineering challenge). I also saw pictures of upside-down mounted HT antennas inside the corvettes, on the roof cross bar.

I have used glass mounts before. Its a compromise, but they work(ish). It will be better than an HT. Just be sure you don't trash the window seal when you roll it up. I would be more prone to use this... Uses something like superglue to mount to the glass. It will look a lot cleaner and when you decide to remove it, you will never know it was on the glass. https://www.amazon.com/TRAM-1192-Pre-Tuned-150-154-Dual-Band/dp/B07B9V77BH/ref=asc_df_B07B9V77BH/?tag=hyprod-20&linkCode=df0&hvadid=270610367741&hvpos=&hvnetw=g&hvrand=14561024409338638345&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9008161&hvtargid=pla-574076094856&psc=1

Steel plate with one sticky side + mag mount. I think Midland has them bundled with their radios. If it was me, I'd try to use 3M Heavy Duty Double Sided Tape with 16GA or thicker steel plate. The tape is available on Amazon in different widths and thicknesses. It's a bitch to remove, need to use hair dryer or heat gun. I do not use it for antenna mounting (I just drill), I use it for other applications where I can't use bolts, rivets etc. Other option: see if you can fabricate a bracket that'll go under the bolts that hold the hood/trunk hinges, and use 1/2 or 5/8 antenna for better efficiency.

I still do all my programming in an XP virtual machine running in Ubuntu!

Yes it is

By the way, if you are planning on a super GMRS repeater, consider installing a JPS SNV-12 voter and two or three diversity antennas and receivers on site. You can pick up 5 to 7 dB effective gain on the receive side this way. Bear in mind, it is only practical for a single CTCSS tone unless you break out the tone path and use some transmission gates and logic to steer the tones to a community repeater panel. Your mileage may vary... Sent from my SM-T350 using Tapatalk