Many if not most handheld, (HT) radios come with pre tuned either dual or tri band antennas. Many are tuned to the 2m, 70cm and the 1.25 meter ham frequencies. They will/do work fine for GMRS. However, if you want to maximize the power output and reach of your radio on GMRS you might consider getting a GMRS specifically tuned antenna.
The GMRS band covers 462 to 467 MHz. The 70cm ham band covers 420 to 450 MHz. Usually the antennas are tuned to the middle of the band. So these 70cm stock antennas are probably tuned to 430/440 mHz. The middle of the GMRS band is roughly 464 MHz. That is not a big difference that is why they work on GMRS.
A quarter wave antenna for GMRS is only 6″ long. Half wave 12″ long. 70cm would be 6 1/2 and a hair over 12″. Again you can see not a big difference. If you were to measure this on an SWR meter the difference wouldn’t be much either. However, even the slightest difference means that not all of your power is going out the end of the antenna if you are transmitting on GMRS with a 70cm antenna.
My main HT is the Wouxun UV9Px. Awesome radio. Listed as an 8+ watt radio. I have tested it up to over 12w. It is mainly a ham radio that is modified for GMRS. It came with the usual stock dual band 2m/70cm antenna. Works perfectly fine. I also have a Comet dual band antenna which is about 15″ long and does work better than the stock antenna. But it is still not a GMRS tuned antenna. Recently I ran across a new antenna called the Melowave Bandit-G GMRS specific antenna for HT’s. So I have one coming from Buy Two Way Radios and will be testing and comparing to the others.
Given our recent efforts to establish a NEPAGMRS simplex relay network I figure that I will try to squeeze as much distance out of my HT as possible. We will see what happens.
NEPAGMRS uses the Bear Creak 725 repeater. That means that the repeater receives the transmission from your radio on 467.725 and re-transmits it on 462.725. That is a 5Mhz offset. Most GMRS radios have that offset already setup in the radio. The Bear Creek 725 is setup with tone codes of D131N. That is a DCS tone code. It is set for both the RX and TX frequency. You need to set your radio tones to match those of the repeater. If you don’t have the tone code set for the TX repeater frequency 467.725 then the repeater won’t hear your transmission. Analog codes, CTCSS, and digital codes, DCS, work exactly the same way there are just a lot more codes to use with DCS.
If a person is on the GMRS channel 22 simplex with NO tone codes set on their radio they will hear all of the transmissions coming from the repeater. (remember the repeater is transmitting on 462.725 with a D131N tone.) However, they will not be able to transmit back since they would also be transmitting on the 462.725 frequency. (Remember the repeater receives on 467.725 with a tone of D131N). Since they do not have a RX tone set on their radio it does not filter anything out allowing them to hear all signals that are within the range of their radio.
This can be confusing. Think of tone codes as filters. They filter out all other signals from the radio. The tone code is an inaudible tone that transmits with your radio transmission. When you have tones set your radio will only allow signals in and out that have that tone embedded in the signal. If you don’t have any tones set you will hear everything.
Happy Thanksgiving. There are now some links on the site for radio equipment and accessory discounts. NEPAGMRS gets $15 off of our order at Radioddity. 10% off at TIDRadio and 7% off at Bettersaferadio.com. There are also links for Ham Radio Prep and Baofeng Tech. They are affiliate links. We will receive a commission on sales clicked through those links. We will continue to seek out discounts and savings for the NEPAGMRS group.
As a licensed radio service, GMRS, the General Mobile Radio Service, operates in the 462 and 467MHz range. Most people that use GMRS, not all, but mostly GMRS is used in groups. As a radio standard, any GMRS radio can talk to any other GMRS radio. If you get a group of people, or just two people who want to talk to each other, GMRS would be a good choice: no test, low license fee, easy operate, clear voice.
If you already take a GMRS handheld radio, this may happen to you a lot. You may hear people talking on say CH16, but every time you try to talk to them, no one reply. They’re not ignoring you, the truth is that they can’t hear you. You can’t talk to them unless you configure your radio to use one of those special repeater channels, and set it all up.
GMRS is limited to 22 channels plus 8 more special repeater channels. For example, this is the frequency chart of UV-5G. You can see that CH1-CH22 are standard channels, and CH23-30 are repeater channels.
Many radios have channels that you can configure to use as repeater channels, but you’re limited to only those special eight repeater channels all the time. Some GMRS radios have extended DIY repeater channels, CH31-CH54 except for the common CH23-CH30. Such as our BAOFENG UV-9G and G11S. You would get a total of 4 groups of repeating frequencies to set different CTCSS/DCS and reduce the interruptions. If your GMRS radio is repeater capable, you can set up to use special channels 23 through 30 to talk on a repeater.
Repeater channels share and overlap with the regular 22 GMRS channels, this may cause much confusion. What is the difference between repeater channels and simplex channels (what we call regular channels)? Don’t know what needs to be set up to talk through a repeater? Then let’s quickly go over some of the definitions.
Simplex means talking directly from radio to radio, from walkie-talkie to walkie-talkie. Just pick up your radio, press the PTT button, and talk to your friends on your walkie-talkie, direct radio to radio communication. This is called the simplex GMRS channel. You don’t have to worry about frequencies because they’re pre-programmed well in every channel.
GMRS repeater channels are different than the simplex channels. The main difference is that a repeater channel is two channels combined to frequencies, combined on a GMRS radio. There are two channels or two frequencies that transmit and receive when you’re using one of the repeater channels. The radio automatically transmits on one frequency and receives on another frequency. This is how the repeater works. When you’re talking with your friend, all your GMRS radios using that repeater channel are transmitting out on one frequency. Then you can talk to each other in the further range.
I have a love/hate relationship with FRS/GMRS radios. They are inexpensive, and you can buy them practically anywhere. They are great for the kids to play with, and are very useful when camping, boating, hiking, or driving in a convoy with your friends. However, the range is short and the antennas are not (usually) replaceable. Nevertheless they work pretty well as long as everyone has the same brand of radio. But if you are trying to talk to people who have different a different brand of radio than yours, things can get a bit trickier.
This page will probably help you out if:
You have GMRS or FRS radios from different manufacturers and you can’t get them to talk to each other.
You have a GMRS radio that sets CTCSS or DCS codes directly (i.e. Cobra HH450, Baofeng GMRS-V1, Baofeng GMRS-50X1) and you want to communicate with other GMRS/FRS radios that use privacy codes.
You enjoy reading arcane radio related stuff.
The easiest way to make different manufacturer radios talk to each other is to put them on the same channel and turn off the privacy codes (or sub codes, or interference eliminator codes, or whatever your radio calls them). If you want to use a privacy code, keep in mind that they don’t give you any privacy. You can usually pick one that’s less than 38 and it will work. My guess is that you already tried it and it didn’t work, so you went a searching and found this page.
Channels and Frequencies
Almost all FRS and GMRS radios use channel numbers as a substitute for the frequency (the Baofeng GMRS-50X1 lets you set the frequency directly). The frequencies and channels are defined by the FCC. Note that while FRS and GMRS share the same frequencies and channels, FRS radios are limited to lower power output. If you are only communicating over short distances and there are many nearby FRS/GMRS radios, you may be better served to use channels 8-14. On the other hand, if you want to maximize the distance of your communications, you should choose channels 1-7 or 15-22.
Channel
Frequency
FRS Power
GMRS Power
01
462.5625
2 W
5 W
02
462.5875
2 W
5 W
03
462.6125
2 W
5 W
04
462.6375
2 W
5 W
05
462.6625
2 W
5 W
06
462.6875
2 W
5 W
07
462.7125
2 W
5 W
08
467.5625
0.5 W
0.5 W
09
467.5875
0.5 W
0.5 W
10
467.6125
0.5 W
0.5 W
11
467.6375
0.5 W
0.5 W
12
467.6625
0.5 W
0.5 W
13
467.6875
0.5 W
0.5 W
14
467.7125
0.5 W
0.5 W
15
462.5500
2 W
50 W
16
462.5750
2 W
50 W
17
462.6000
2 W
50 W
18
462.6250
2 W
50 W
19
462.6500
2 W
50 W
20
462.6750
2 W
50 W
21
462.7000
2 W
50 W
22
462.7250
2 W
50 W
467.5500
50 W
467.5750
50 W
467.6000
50 W
467.6250
50 W
467.6500
50 W
467.6750
50 W
467.7000
50 W
467.7250
50 W
Many handheld FRS/GMRS radios do not transmit at the maximum power limit. For example, a Motorola T600 has a maximum transmit power of 1.5 W. My Cobra HH450 can transmit on GMRS at 1 W, 2 W, or 3 W.
In September 2017 the FCC combined and standardized the FRS and GMRS frequencies, which codified the common practice used by most manufacturers. Most radios built before September 2017 use the modern channel frequencies in the chart above. Some older GMRS only radios, like the Midland MXT105, don’t transmit on channels 8-14 because those channels were previously designated as FRS only. The good news is that most of those radios just omit those channels from their settings. Channel 20 on the MXT105 works with everybody else’s channel 20.
The last 8 frequencies in the chart, the ones without channel designations, are for use as repeater input frequencies. Most GMRS radios are designed for simplex operation and can’t transmit on these frequencies. Which mostly doesn’t matter because there are very few GMRS repeaters out there.
What is Squelch Anyway?
GMRS/FRS channels mostly just work no matter who manufactured the radio. However, it’s not so smooth when it comes to the so called privacy codes. Motorola calls them interference eliminator codes. Uniden sometimes calls them sub codes. All these words are synonyms for either analog or digital squelch, and sometimes a synonym for both, which is unfortunate. If you are a ham radio operator, you probably know what squelch means. If the word squelch makes you think of that time you almost threw up and it went all the way to the back of your throat, don’t worry, it’s not that. Here’s a metaphor to explain.
Say you have 10 friends all in the same room at the same time. You assign two of your friends code 1, two friends code 2, two friends code 3, and so forth. Everyone starts whispering except one person, who starts talking. It’s easier for you to listen to the person talking, because they are louder than everyone else. That’s squelch. Now, everyone starts talking at the same time. If you are assigned to code 4, you try really hard to only listen to the other person who is assigned to code 4. That’s tone squelch. But if you really want to listen to the conversation going on between the two people assigned to code 5, you could do that too. In other words, squelch just tells your radio what to listen for, it has nothing to do with what is transmitted.
You can test this out for yourself if you have two FRS/GMRS radios. Set them both to the same channel, and then set one of them to use privacy code 5. Turn off the privacy code, or set it to 0, on the other radio. When you transmit on the radio with privacy code 5, you will still be able to hear the transmission on the radio with the privacy codes off. But when you transmit on the radio with the privacy codes off, the radio set to privacy code 5 won’t be able to hear. It’s not that the transmission wasn’t sent, it’s just that the radio is ignoring all transmissions without privacy code 5.
In real life, there are three basic types of squelch. The first is based on signal strength. The signal received by your radio has to be of a certain strength in order for your radio to decide it’s important enough for you to hear it. Turn the squelch down and you will hear all kinds of fuzzy signals. Turn the squelch up and you will hear only the stronger signals. Most FRS and GMRS radios don’t have this type of squelch setting.
The second type of squelch works by adding a low frequency tone to the transmission. The receiving radio ignores all signals that do not contain the specified tone. The tone is stripped out by the receiving radio before sending the signal to a speaker or headset. The real name for this method of transmission is Continuous Tone-Coded Squelch System or CTCSS. Most modern FRS and GMRS radios have CTCSS, but most of them don’t call it CTCSS.
Digital Coded Squelch or DCS is the third type, and it works by adding a sub-audible digital bitstream to the transmitted audio. The bitstream is used to transmit a code along with the audio. The radio ignores signals that do not include a bitstream with the specified code. Many FRS and GMRS radios, especially the higher end models, have DCS, but like CTCSS, most of these radios don’t call it DCS.
Privacy Codes
In an effort to avoid a long discussion like we just had about CTCSS and DCS, the FRS and GMRS radio manufacturers came up with different words to describe tone or digital squelch. Motorola uses “Private Line” or “PL” codes. They also use “interference eliminator codes”. Radio Shack (remember them?) used to call them “quiet codes”. Many manufacturers call them “privacy codes”. These consumer friendly terms refer to both CTCSS and DCS. Which makes everything confusing when trying to figure out how to make radios from different brands talk to each other. To make the description easier from here on out, we’ll just call them privacy codes. Just remember, they have nothing to do with privacy.
You don’t have to use privacy codes. The easiest way to make your different brand radios talk to each other is to turn the privacy codes off. On many radios you turn the privacy code off by setting it to 0.
Some radios don’t have privacy codes, like the Midland LXT118. That means you hear everyone on your channel, whether they use a privacy code or not. But it also means that nobody using a privacy code can hear you. They have to turn their codes off in order to listen to your transmission.
I love my Cobra HH450. It doesn’t have the FRS-only frequencies because it has a detachable antenna; the FCC doesn’t allow detachable antennas on FRS radios. It has the pre-2017 GMRS channels and it transmits and receives on the marine VHF channels. It’s submersible and receives NOAA weather broadcasts. It’s a great radio to take to the lake. Even better, it doesn’t have “privacy codes”. It has a way to turn on CTCSS and set the tone, or you can turn on DCS and set the code. This approach works great for a ham operator like me, but may be overwhelming for many who purchase these radios. So how do I know which privacy code to use on my Motorola MT351R when I set a CTCSS frequency of 88.5 Hz on the Cobra?
CTCSS-based Privacy Codes
CTCSS works by adding a low frequency tone to the transmitted signal. Radios configured to use CTCSS filter out any signals that don’t contain the designated low frequency tone. There are more than 50 tone frequencies that work for CTCSS, but only 38 of them are commonly used on FRS or GMRS radios. A few radios (like the Cobra HH450, Jetstream JT270M, Baofeng GMRS-50X1 and Baofeng GMRS-V1) allow you to set the tone frequency directly. For most radios the manufacturer represents the various tone frequencies with a “privacy code”. Lucky for us, they mostly chose the same assignments. The following chart shows a map between the CTCSS frequencies and privacy codes. The “Common” column is used by most manufacturers, including:
Cobra
Midland
Motorola
Uniden
Backcountry Access
Rocky Talkie – versions sold after July 16th 2020
Freq (Hz)
Common
Cherokee 465
Motorola Sport
Radio Shack
Retevis RB15
67.0
1
1
1
1
69.3
2
69.4
2
71.9
2
3
3
3
74.4
3
4
4
4
77.0
4
5
A
5
79.7
5
6
6
82.5
6
7
7
85.4
7
8
8
88.5
8
9
B
9
91.5
9
10
10
94.8
10
11
11
11
97.4
11
12
C
12
100.0
12
13
13
103.5
13
14
14
107.2
14
15
D
15
110.9
15
16
16
114.8
16
17
17
118.8
17
18
E
18
123.0
18
19
19
127.3
19
20
F
20
131.8
20
21
21
136.5
21
22
G
22
141.3
22
23
23
146.2
23
24
24
151.4
24
25
25
156.7
25
26
26
26
159.8
27
27
162.2
26
28
28
28
165.5
29
167.9
27
29
30
30
171.3
31
173.8
28
30
32
32
177.3
33
177.8
179.9
29
31
34
34
183.5
32
35
186.2
30
33
36
36
189.9
34
37
192.8
31
35
38
38
196.6
36
199.5
37
203.5
32
38
41
206.5
39
210.7
33
40
43
218.1
34
41
44
225.7
35
42
45
229.1
43
233.6
36
44
47
241.8
37
45
48
250.3
38
46
49
254.1
47
DCS-based Privacy Codes
Digital Coded Squelch works by transmitting a digital bitstream with the audio. The bitstream is encoded with error correction and can accommodate 512 different squelch codes. These codes are typically represented as an octal (base 8) number. However, because of the way the codes are packed into the bitstream, there is a possibility of misalignment errors upon decoding. To reduce the potential for decoding errors, most manufacturers only use 83 of the 512 codes. However, some Midland radios and the Baofeng radios can use any DCS code. In fact, the Baofeng and Jetstream radios can use inverted DCS codes (too complicated to explain here). Not sure why you would ever want or need that, so I’ve omitted them from the chart.
Many radios just have one set of numbered privacy codes, and you have to magically know where it switches from CTCSS to DCS. This is how my Motorola MT351R works. Privacy code 38 is CTCSS with a 250.3 Hz tone, privacy code 39 is DCS using code 023. The MT351R has 121 privacy codes, 38 CTCSS tones, and 83 DCS codes.
The DCS-based privacy codes have been implemented two different ways. Uniden, Motorola, and Backcountry Access just keep the privacy code numbers going, and switch from CTCSS to DCS at code 39. Midland and Cobra have a separate DCS mode, and the privacy codes start over at 1.
In this chart the “Common” column is used by the following manufacturers radios:
Backcountry Access
Motorola
Uniden
Rocky Talkie – versions sold after July 16th 2020
DCS Code
Baofeng GMRS-V1
Common
Cobra
Midland
Retevis RB15
023
D023N
39
1
1
1
025
D025N
40
2
2
2
026
D026N
41
3
3
031
D031N
42
4
4
032
D032N
43
5
5
5
036
D036N
84
043
D043N
44
6
6
7
047
D047N
45
7
7
8
051
D051N
46
8
8
9
053
D053N
85
054
D054N
47
9
9
11
065
D065N
48
10
10
12
071
D071N
49
11
11
13
072
D072N
50
12
12
14
073
D073N
51
13
13
15
074
D074N
52
14
14
16
114
D114N
53
15
15
17
115
D115N
54
16
16
18
116
D116N
55
17
17
19
122
D122N
86
125
D125N
56
18
18
21
131
D131N
57
19
19
22
132
D132N
58
20
20
23
134
D134N
59
21
21
24
143
D143N
60
22
22
25
145
D145N
87
152
D152N
61
23
23
27
155
D155N
62
24
24
28
156
D156N
63
25
25
29
162
D162N
64
26
26
30
165
D165N
65
27
27
31
172
D172N
66
28
28
32
174
D174N
67
29
29
33
205
D205N
68
30
30
34
212
D212N
88
223
D223N
69
31
31
36
225
D225N
89
226
D226N
70
32
32
38
243
D243N
71
33
33
39
244
D244N
72
34
34
40
245
D245N
73
35
35
41
246
D246N
90
251
D251N
74
36
36
43
252
D252N
91
255
D255N
92
261
D261N
75
37
37
46
263
D263N
76
38
38
47
265
D265N
77
39
39
48
266
D266N
93
271
D271N
78
40
40
50
274
D274N
94
306
D306N
79
41
41
52
311
D311N
80
42
42
53
315
D315N
81
43
43
54
325
D325N
95
331
D331N
82
44
44
56
332
D332N
96
343
D343N
83
45
45
58
346
D346N
84
46
46
59
351
D351N
85
47
47
60
356
D356N
97
364
D364N
86
48
48
62
365
D365N
87
49
49
63
371
D371N
88
50
50
64
411
D411N
89
51
51
412
D412N
90
52
52
413
D412N
91
53
53
423
D423N
92
54
54
431
D431N
93
55
55
432
D432N
94
56
56
445
D445N
95
57
57
71
446
D446N
98
452
D452N
99
454
D454N
100
455
D455N
101
462
D462N
102
464
D464N
96
58
58
77
465
D465N
97
59
59
466
D466N
98
60
60
503
D503N
99
61
61
506
D506N
100
62
62
516
D516N
101
63
63
82
523
D523N
103
526
D526N
104
532
D532N
102
64
64
85
546
D546N
103
65
65
565
D565N
104
66
66
606
D606N
105
67
67
612
D612N
106
68
68
624
D624N
107
69
69
627
D627N
108
70
70
631
D631N
109
71
71
632
D632N
110
72
72
93
645
D645N
654
D654N
111
73
73
95
662
D662N
112
74
74
664
D664N
113
75
75
703
D703N
114
76
76
712
D712N
115
77
77
99
718
723
D723N
116
78
78
100
731
D731N
117
79
79
732
D732N
118
80
80
102
734
D734N
119
81
81
743
D743N
120
82
82
104
754
D754N
121
83
83
105
Some Midland radios, like the T70 series, only have 83 DCS privacy codes. Others, like the MXT105, have 104. The first 83 are the same across all Midland radios, but if you pick code 99 on your MXT105, most other radios will have to disable privacy codes in order to hear you.
Hopefully this helps make sense of the sometimes confusing so-called privacy codes on FRS and GMRS radios. If your radio isn’t listed here or if you can confirm or dispute any information on this page, I’d love to hear from you. Email correspondence, suggestions, corrections, or complaints to jared@k0tfu.org.
In preparing for setting up and testing our simplex network you should set up your radio or radios on GMRS 22R (repeater) and 22S (simplex). If you have a radio with dual VFO’s you can set one VFO to each channel. This will make it easy to monitor both at once for testing. If your radio doesn’t have dual VFO’s you can either use two radios or just switch frequencies when testing.
For ease of memory, 🙂 we have set the tones the same for both the repeater and simplex 22 channel. TX D131N RX D131N.
The NEPAGMRS group is currently working on creating a simplex relay network. Should the repeaters go down we need to be able to still communicate. Click here for the details.
If you are reading this you have found our website. We have combined the NEPAGMERS and the NEPAGMRS sites into one. We will be posting updates here to this blog as well as on each page on the site as well as on the Facebook group. On the main page of this site at the top right there is a direct link to the FB Group Page.
Lee, WRFM780 has a secondary repeater up and running on GMRS repeater 18. 462.625/467.625 Tones are TX D205N RX D205N. Check it out see if you can reach it from your location.
Another great idea from the Community Emergency Radio Association
Neighborhood Radio Watch Groups are informal groups intended for use by the general public so neighborhood residents have a means of staying in touch through the use of radios and a radio communications system to educate and prepare residents of a community on security and safety events and to help themselves when traditional communication methods fail or are not available.