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The most official designation of frequencies as channel numbers that I have every found comes from here: § 95.563 FRS channels. The FRS is allotted 22 channels, each having a channel bandwidth of 12.5 kHz. All of the FRS channels are also allotted to the General Mobile Radio Service (GMRS) on a shared basis. The FRS channel center frequencies are set forth in the following table: 1 ................................................ 462.5625 2 ................................................ 462.5875 3 ................................................ 462.6125 4 ................................................ 462.6375 5 ................................................ 462.6625 6 ................................................ 462.6875 7 ................................................ 462.7125 8 ................................................ 467.5625 9 ................................................ 467.5875 10 .............................................. 467.6125 11 .............................................. 467.6375 12 .............................................. 467.6625 13 .............................................. 467.6875 14 .............................................. 467.7125 15 .............................................. 462.5500 16 .............................................. 462.5750 17 .............................................. 462.6000 18 .............................................. 462.6250 19 .............................................. 462.6500 20 .............................................. 462.6750 21 .............................................. 462.7000 22 .............................................. 462.7250 And here https://apps.fcc.gov/kdb/GetAttachment.html?id=biZxuanIfZOUqdjvLHdsyw%3D%3D&desc=888861%20D01%20Part%2095%20GMRS%20FRS%20v01&tracking_number=239603 https://www.law.cornell.edu/cfr/text/47/95.563 Although within part 95e, standard channel number are not defined as they are in the FRS, it does seem logical that since they are defined for FRS and both services share 22 of the same frequencies that there is a logical numeric correlation that can (as has) been made between the two. Michael WRHS965 KE8PLM

If the repeater is currently only being used by members of a single family under a single license, the only call sign heard during conversations should be that of the family’s call sign, either verbally or in CW (morse code). If you have that call sign, you can get the name and address from the FCC database. https://wireless2.fcc.gov/UlsApp/UlsSearch/searchLicense.jsp. If it is a physical address you can visit them, send a letter, or do a public records search to get the phone number and call. If the repeater is being used by any party not a family member of the licensee, the repeater is required to self identify every 15 minutes of use. Then repeater should be giving out the licensee’s call sign in English or CW. Again, once you have the call sign you can look them up as mentioned earlier. In neither case above do you need tone scanning. Having a code is never required to listen to a repeater nor any simplex GMRS communication. If you have tone squelch disabled on your radio (factory default on all GMRS radios I know of) you can listen to everything on that frequency and, by extension, every call sign used on that frequency. If the callsign is being given in morse code you can either learn morse, or you can download an app for the smart phone that will translate it for you. ‘Morse-It’ is what I use. If neither the repeater users nor the repeater identify as required per the rules, well that is going to be far more difficult. I do not have any practical advise for you on that one. That may require some serious fox hunting and stalking. I would leave well enough alone there and seek the use of legal repeater alternates. Hope that helps. Michael WRHS965 KE8PLM

I thought I would do a report out of some testing I conducted this weekend. One of my original curiosities has been how much signal actually finds itself being picked up by the offset antenna when the other is used to transmit in the same band. To settle this I separately transmitted using my GMRS and amateur radios (70cm) and measured the signal level present on the non-transmitting antenna. While transmitting at 50w, the offset antenna showed about -15dBm (about 25 uW or .04V ) of signal present. This was nearly the same regardless of direction. This tells me a couple of things: 1) The power levels being picked up by the opposing antenna is well with the safe range of the receiver connected to the opposing antenna. 2) Expect serious desense of the opposing receiver during those periods when transmitting on the other radio within the same band as the receiving radio. In addition, I did do some operational tests to see if there was any material desense of the opposing radio when operating in different bands. So far, no desense of concern. This was checked while listening to weak VHF signals on the amateur radio while transmitting on GMRS, and transmitting VHF while listening to weak signals on the GMRS radio. This was purely a subjective test under conditions in which I know the desired incoming signal to both radios was -110dBm or less. So, not bad. Michael WRHS965 KE8PLM

I can see how you would look at it that way. Knowing what the code is and using to gain unauthorized access are two very different things however. The code to access a repeater is not private, nor is it encrypted or allowed to be encrypted. In fact it is transmitted in the open, just like you must do with your voice and your callsign. You merely have to be within ear-shot of the transmitter sending it to learn what it is. For those that may read this post and not already know it, All Repeaters are private property. Even though you may know what the code is, and even though the repeater owner may publicly identify their access code (like a good number do on this site for example), you do need the owner’s permission to use their equipment. Most repeater owners expect you to contact them directly to gain permission (phone, email, or via this site). Others may give carte-blanche permission by public notice within a public disclosure about their repeater such as “All licensed GMRS users are free to use the repeater. Be courteous, identify and keep your transmissions brief”. Michael WRHS965 KE8PLM

It's a 10W transmitter but by the time the signal is passed through the notch duplexer inside, the output is 5W. Because of this, we market these as 5W repeaters and that's the power the FCC has certified them at. If the transmit and receive frequencies were further apart than 5 MHz, the duplexer would not have as much loss and you'd see something closer to 10W.

Should be more than a 1/4 wave or a multiple if less than70 CM (about 2 feet)

You can search using the map instead of the repeater listing. Just click on the map tab on the MyGMRS home page. That should help you find what's close to you. Keep in mind though, that to use any of the listed repeaters (or any that aren't listed) for transmitting still requires permission from the repeater owner. If you click on one of the repeaters on the map, it will give you the details of that repeater.