mbrun

You are most definitely on the right track. If I needed full simultaneous duplex comms all both radios then my current arrangement is definitely not appropriate. But for one man in shack doing voice on one service at a time it is very workable. Now, if I ever do decide to put up a repeater on my site then suddenly separation and serious filters will be needed. $$$$$$$$ Yep that separation in the near-field is a good thing. Definitely appreciate the feedback. Michael WRHS965 KE8PLM

That is one of the beauties of the radio hobby and a serious enthusiast who has test equipment. You get to theorize, experiment and observe the results to your questions first hand. Quite wonderful and fun indeed. Michael WRHS965 KE8PLM

It could affect it depending upon the degree of deformation. The most absolute way to know is to check the SWR before and after. My mobile feed-line experiences very slight compression and the SWR remains in the excellent range. You can probably do some tests by using your fingers to compress the cable while you are taking readings to see how much compression the cable takes between your readings go hay-wire. Michael WRHS965 KE8PLM

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

There are repeaters on 462.700 located in Cincinnati and Dayton. both owned by the same person. Odds are that in Oxford you can hear and likely access both with the right equipment. Both are extremely high profile and are the most widely used in the region. All that said, you must have permission to use them. A phone call and discussion with the owner is required in advance. Contact information is available on this site. 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 used to be the limit was a hard and fast max 20’ above the building or tree to which the antenna was attached, with further limits according to FAA restrictions when you are in proximity of an airport. In 2017 the FCC removed that 20’ limit for GMRS and instead replaced it with a redirect of the user to the 200’ AGL and FAA limits. § 95.1741 GMRS antenna height limits. GMRS station antennas must meet the requirements in § 95.317 regarding menaces to air navigation. See § 95.317 and consult part 17 of the FCC's Rules for more information (47 CFR part 17). § 95.317 Registration of antenna structures that may constitute a menace to air navigation. (a) Each antenna structure used for a Personal Radio Service station is subject to the antenna structure rules set forth in part 17 of this chapter. In particular, the owner of an antenna structure that is more than 60.96 m (200 ft) in height above ground level (see § 17.7 of this chapter for specific criteria) may be required to notify the FAA and register the antenna structure with the FCC. Further, stations located on or near a military or public-use airport with an antenna structure that is more than 6.10 meters (20 feet) high may have to obey additional restrictions. The highest point of the antenna must not exceed one meter above the airport elevation for every hundred meters of distance from the nearest point of the nearest airport runway. Differences in ground elevation between the antenna and the airport runway may complicate this formula. For stations near an airport, see http:// appsint.fcc.gov/UlsApp/AsrSearch/ towairSearch.jsp to figure the maximum allowable height of the antenna. Consult part 17 of the FCC's Rules for more information (47 CFR part 17). Michael WRHS965 KE8PLM Edit 1: I found the link below on FAA website that allows user to perform actions to help them determine if submission to FAA is requested. I got a kick out of the results. If I place an object the size of a basketball on my property, it requests I submit a request for approval on the basis it may interfere with aeronautical signal reception. https://oeaaa.faa.gov/oeaaa/external/gisTools/gisAction.jsp. BTW, if I place a tower 1000’ on my property it is still ‘requests’ that I file. Its message did not change to indicate I must file. Weird, considering 200’ is a hard and fast threshold for submission. Edit 2: Try list link. Hopefully it works better. https://oeaaa.faa.gov/oeaaa/external/gisTools/gisAction.jsp?action=showNoNoticeRequiredToolForm

You can scan any frequency your radio is actively tuned to. If it is tuned to a simplex frequency that is what gets scanned. If it is tuned to the repeater output frequency (same as simplex) that again is what gets scanned. If you want to scan for the code being used to activate the repeater then you have to be close to the person that is actively talking on the repeater AND you have to have your radio configured to Rx that repeater’s input frequency. Some radios have a function (called ‘Reverse’) that makes switching to the repeater input frequency easy thus making scanning for the code easy. It is pretty common on amateur radios, but not on GMRS. Michael WRHS965 KE8PLM

Glad you figured it out. Michael WRHS965 KE8PLM

The mast is not PVC, although the side mount bracket is made is. The main mast is HD fiberglass mast and is very rigid; nearly straight as an arrow too at its full 56’ extension (with antenna). There are three sets of guy rings on the mast for use when it is fully extended. PVC would be a limp noodle in this application and would definitely snap, probably under its own weight, and perhaps even without wind. The venture to guess that the side mount bracket would likely outlive the antenna in high winds. It is pretty beefy and sees very little load. Michael WRHS965 KE8PLM

Yeh, I agree with you. With an SWR that high I would not operate the radio except for a coupe of seconds to do a brief SWR test until your number is down in the 2:00:1 range Dummy loads are widely available on Amazon and virtually everywhere SWR meters are sold. They are used whenever you are using an SWR or dedicated power meter to confirm the power output of a radio. A quick search on Amazon for “RF Dummy Load, 50 Ohm“ and it will should turn up many results. Make sure you get one with a frequency range that includes the frequency of your radio as well as one, a connector compatible with your equipment, and a power rating equal too or greater than the max power of the radio(s) you might want to test. Below is an image of one hooked up to SWR Meter and Radio for simple power test. Note the 1.00:1 SWR reading which is what you should have with a dummy load when hooked up as shown. Once you have a dummy load, and assuming it shows you a 1:00:1 as it should, the odds are better now that the meter is OK and the problem is with Antenna and/or feed-line and/or adapters you’re using. In this case, additional test equipment and procedures will be needed. If you don’t know anyone with test equipment, perhaps look up on the ARRL website for amateur radio clubs in your area. If you can make contact with one of those clubs I am certain that many members will have the equipment necessary and would be happy to assist you. Michael WRHS965 KE8PLM

Yes it could be the meter, but it is equally likely you have an issue with your feed-line, antenna, and any adapters you may be using. Do you have a dummy load available? Putting the dummy load on the SWR meter in place of an antenna and feed-line should give you a 1:1 match. Anything other than that would be a strong indication of an issue with the meter. Do you have a friend that has a SWR meter that you can contrast yours with? Know of someone with a NanoVNA. Each of these would help you troubleshoot to the next level. Michael WRHS965 KE8PLM

I then have a follow up question. Are not all radios programmed with "standard" channels? I see some people refer to channels as frequencies, while others refer to them as channels? Are having "simpler" channels a way to make "newbies" more comfortable with using the GMRS radios? I was looking at this handy dandy FRS/GMRS Radio Quick Reference Card (click). It seems to show a channel and a frequency. Was it someones attempt to make it easier? Thanks everyone. The simple answer to your question regarding channelization is YES, channelization is an attempt to simplify radio for the masses. And it certainly has merit and works well for the masses. Channel ‘15’ is a lot easier to remember for most folks than remembering 462.5500 MHz in the GMRS. In its most simple form, a channel is a simply an alias way of express a frequency. A channel can be more than just one frequency. Channel 15 in the Citizen’s band radio service is not the same as Channel 15 in the GMRS. Similarly, Channel 15 in terrestrial TV broadcast is different from 15 in CB, GMRS and every other RF communication service. In its more advanced form, a channel is actually a group of settings what when used together enable some form of RF communication to occur between a transmitter and receiver. If the receivers settings complement the transmitter settings communication can occur. Depending upon the radio and service, the channel will include such things as a frequency and other factors such as modulation type (AM, FM, etc.), modulation depth (bandwidth), squelch codes (PL, DLC, CTCSS, DCS) and many other settings. A programmable radio has memories. Memories in most cases are synonymous with ‘Channel’ as well since each memory holds a frequency assignment and all the other necessary factors to enable communications. No, not all radios have standard channels programmed into them, but that is certainly something the FCC is trying to make happen a manufacturer wishes to get their radio certified for using in the Personal Radio Services under Part 95 of the rules. As you look at the current crop of part 95E GMRS radios you will see that they do in-fact have factory-programmed memories preset to use the standard GMRS frequencies so that no additional programming is required to use the radio. Programming of additional memory configuration (i.e. channels) becomes optional. Hope this helps. Michael WRHS965 KE8PLM

Welcome to myGMRS. Hope you enjoy your time here and learn things. As you knowledge increases, be certain to pass on. Again, Welcome. Michael WRHS965 KE8PLM

Two radios, two services, two antennas. Family is licensed for GMRS only while I am licensed for both. Family knows which radio they are licensed for and permitted to transmit on. Neither radio in the shack is capable of transmitting outside its approved frequency range. While I don’t “need” to operate both at the same time (as I can talk on only one radio at a time), I do regularly monitor both services. So I can still monitor one service, albeit at a lower level, while operating on the other.

In a number of posts on this forum I have mentioned my intent to side mount my amateur radio antenna on the same mast that I use for the GMRS antenna. I can now say that it is done and has been working for almost a week. As promised elsewhere, here are some pics. The side mount bracket is home crafted and painted a color similar to the main fiberglass mast. The amateur antenna is currently about 6-1/2ft below the bottom of the GMRS antenna. There is about 21” between the amateur antenna and the nearest metal (the GMRS feed line). I am using LMR400 feed-line for both antennas and have ferrite chokes installed over the coax. I have not yet detected any material interference or objectionable desense in the GMRS radio while transmitting on the amateur radio. I do however observe one bar on the GMRS radio’s meter flutter while transmitting at 50w UHF on the amateur radio, if the GMRS radio is receiving a usable low-level signal at the point I key up the amateur radio, just not enough to be of concern presently. I will be operating both antennas at the lower height you see in the picture until I am ready to guy the mast at full height, which is about 16’ higher. One of the inquires I received elsewhere is listed below along with my original response. Posted here to prevent derailing another thread. I will be running 50w UHF and VHF, 50w GMRS. I will let you know once it is operational. I may not have it installed for two weeks. I do expect some desensitization of the listening receiver while I am transmitting on the other service, but nothing that I expect will affect my operations. I will have ferrite chokes on the GMRS feed-line to cut down on the noise and reduce ingress from the 2m/70cm since that line will be running parallel to the amateur antenna. Michael WRHS965 KE8PLM

I use the antenna. Currently installed at 40+ feet. LMR400 into the radio shack, then adapter cable to radio. Excellent SWR at the antenna and in shack. No complaints. Michael WRHS965 KE8PLM

Good Day Duncan! Need more info. Lots of possibilities for why it’s not working based on what is not working. What about the setup is working, if anything? Is the power turned on to both radios? How are the radios configured? How are the radios hooked up? Are they hooked up correctly? Is the cable used to interconnect the two radios wired correctly and working? Are you using two antennas or one? Are you using a duplexer? Is it tuned? Is it tuned for the correct frequencies? How do you know it is operational? Are you using the correct ports? How close to the repeater are you when trying to test it with radios? What radios are using to test it with? What do you see happening on your repeater radios when you key up the radio you are testing the repeater with? Does the transmit radio actually transmit a signal when using the HH mic in repeater mode if the receive radio is turned off? Does the receive radio show that it is actually receiving a signal when the transmit radio is turned off? Michael WRHS965 KE8PLM

I believe it is safe to say that the market is too small for manufacturers to make hardware that is 100% specific to the GMRS. Instead what they do is make hardware that can be used for a variety of different services, but mainly for Public Service, Commercial and Amateur radio. Then they adapter it for GMRS. I think they leave some commercial and amateur radio features in the radios to lure folks into buying them because they have “extra” features, even though said features may have no practical use in the GMRS. Quite honestly some of these radios are unnecessarily complex for what the GMRS user really needs or wants. Yes I was referring (in part) to PTT-ID. There is nothing to say that it could not be used in GMRS, just that is currently has limited or no practical use in the GMRS for the masses, whereas in a commercial or public service application it has had lots of practical use according to some folks I have discussed it with. If you do have radios that can both transmit a PTT-ID as well as decode and display it, that could potentially be a benefit to you. If you had a family business and perhaps your own repeater that could leverage it in some manner then again it could be beneficial. Michael WRHS965 KE8PLM

There are loads of apps available use with your smart phone and tablet. They can help you learn to understand it as well as send it. It is still very prevalent in the amateur community although it is no longer a requirement to get one’s license. I have ‘Morse-It’ on my IOS devices as both a learning and a decoding tool. Michael WRHS965 KE8PLM

Good Day. When I started playing with radio back in the 70s I used to wonder the same thing regarding full-wave antennas. If a quarter wave antenna makes for a good working antenna and a half-wave is better, why isn’t anyone using a full-wave antennas. Well, the simple answers are 1) Antennas are larger than their shorter counter parts(a really big issue at lower frequencies) and 2) through testing it has been determined that they are very poor performers. You can be certain that with so much experimentation and research into radio and antennas for over a century that if full-wave antennas performed even remotely better they would be in heavy use. However, 1/2 wave antennas have been determined to be the clear winner. Oddly enough, even the 1/4 wave antenna is in effect a 1/2 wave antenna in that the ground plane (or ground radials) effectively satisfy the function of the missing 1/4 wave portion. If you search the internet you will find the more technical reasons why the full-wave version performs poorly. Michael WRHS965 KE8PLM

Good Day Don. When the radio is configured to send out its ANI-ID (a.k.a. its PTT Identifier) the radio can be also be configured so this very ID is heard locally by the operator via the speaker. The benefit of hearing it locally is that the person transmitting knows when the ID is being sent out so they do not talk over it. Given the length of the DTMF sequence sent out, if silent locally, it would be easily for a user to inadvertently talk over it if. I think you are on the right track with regards to how the ANI-ID may be used in some cases (e.g. repeater access). The way I understand it currently however is that it has has little or practical use in GMRS and probably has no use being on nor being marketed as a “feature” of an GMRS radio. However, when present on a radio used in the commercial or public service space it does have its place. Here is my current understanding: - Some commercial radio services may require the radio to send out a certain code, perhaps in addition to a PL, to gain access to the repeater. - Such commercial services, particular third party leased services that share a frequency amongst many different companies may use the codes as a means of metered usage of a repeater. Perhaps the greater the number of times a given ANI-ID is used during a month, the greater the bill for usage. - When used in a dispatch environment, the received code can be translated to a specific user name so the dispatcher automatically knows who they are talking to without the remote operator having to identify themselves each time. Hopefully this little nugget of additional insight is useful. Michael WRHS965 KE8PLM

Absolutely. Eight of the main GMRS frequencies (462.550, .575, .600, .625, .650, .675, .700, .725) are all allowed 50watts when used simplex or with a repeater. These are often called channels 15-22. Their 467MHZ companions (i.e. the other eight main GMRS frequencies) are not permitted for simplex use. If you were to illegally use the 467MHz Main frequencies for simplex, you are likely to negatively affect local repeaters that use them as their input frequencies, so do not ever do that. You are on the right track. Always use as little power as necessary to get the job done. Finally, you are also on the right track too to pick a simplex frequency that is not being used so as to avoid interference with others. That is always a wise decision. Hope this helps. Michael WRHS965 KE8PLM