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I'm sure I'll eventually come up with something more permanent. Since I tend to drive my vehicles until they fall apart, I may have a hole drilled and a permanent NMO mount installed. Before I do that, however, I want to make final decisions about where I want the radio, etc.

True. I gave up on mag mounts in favor of lip mounts. Too many pinched coax and water leak problems and I'm no fan of coax draped across the roof. Ultimately a lip mount would be my recommendation.

Yes... At least on 467.550 and 467.575 (the input freqs of GMRS repeaters 462.550 and 462.575) per ITU agreement. The sad part is they are allowed and encouraged to run a shipboard repeater output on those two GMRS repeater inputs but at a 10MHz lower split instead of +5MHz GMRS uses.

Another good one that is 16" tall is the Comet SBB1 NMO. That is what I am running on my 2023 Ford Escape. https://www.dxengineering.com/parts/cma-sbb-1nmo It's hard to beat the SBB1 or SBB2 when it comes to short dual band antennas.

Who you calling a freak?

Especially if you get your radio from the Mossad...

OK, been meaning to explain this and this is a good time. The commercial guys here will all tell you there are three tests that we perform when installing a new repeater system out in the field. First test is 12dB sinad with the service monitor connected to the duplexer wit no antenna. Second test is for something called isolation. We drop the input signal down to where the repeater squelches, or stops transmitting and then increase the signal slowly until the receiver just opens back up. What we then look for is the repeater to drop again when the transmitter comes up and then drop back out. If the duplexer isn't tuned correctly, the repeater will 'ping pong' up and down because the TX frequency is getting into the receiver and deafening it to some degree. If it does start to ping pong, we increase the signal level in in TENTH's of a dBm until it stops. At that point, we usually stop the testing, touch up the duplexer tuning and run through all the tests again. The last test is antenna desense. An isolation Tee is connected to the duplexer antenna port and a dummy load is then connected to the output. The tap port has signal injected on it to the point the receiver opens and the signal level is noted. Then the signal is removed, and the dummy load is unhooked and the antenna is connected. The signal is injected again on the tap and increased to the point that the receiver opens again. The difference in the required signal level is the antenna desense for that antenna and repeater system at that site. Now, here's how that applies to what YOU are seeing. With the 12dB Sinad test, you need to understand what that measurement is. That being a ratio of signal to noise in the receiver. Here's a good explanation. https://en.wikipedia.org/wiki/SINAD But it's NOT the minimum signal level that the repeater can hear and open up. That is actually the LAST test (antenna desense) where the signal level is just above the noise floor enough for the receiver to recognize it and hear the PL /DPL. On a repeater running CSQ, the level is going to be lower, because it doesn't need to hear the tone above the noise, just the RF. These readings are gonna be 6 to 12 dB different in their levels. And the basis of where I make the statements about needing to be able to increase signal level a BUNCH to get a noisy signal to be full quieting. It's not a watt or two, unless you are only running 1 watt or less to begin with. That's based on using dB and specifically dBm numbers for power output in place of watts. An example is 30dBm is 1 watt, 33 dBm is 2 watts, 36dBm is 4 watts. on the upper end, 50dbm is 100 watts and 53dBm is 200 watts. So when you look at it that way, and start realizing that to go from just opening a repeater receiver at -119dBm to 12 dB SINAD at -110dBm or so, that 9dB signal level change is HUGE in the percentage of power change when you convert it back to watts. And the best part is you can calculate all this if you have the information about the equipment in play. You need the antenna model (so you know the gain) the coax type and length (to calculate the cable loss) the number and type of jumpers (again cable loss) the duplexer model (insertion loss). Then you need YOUR power level in watts (converted to dBm) and your antenna system numbers as well. The last part is the distance between the antenna's to calculate something called PATH LOSS. With all that you can calculate what the actual signal is at the repeater input from your radio transmitter from miles away. And yes, I have tested this and found that it's accurate within a dB or two. The difference is from signals that bounce off other things and arrive out of phase to the antenna and cancel put part of the signal. This is called Rayleigh effect. (Again, go look it up, NOT typing it all out) but that also explains sitting in traffic and the repeater fading out. Moving 2 feet and the repeater signal coming back.

To be fair that only happens in one region of the world regardless of the SWR...

Picked up a pair on a Cyber Monday special. I was not really interested in them till I watched NotaRubicon's video on them. Tested them from inside a house to about a quarter mile away in thick woods. I was running a chainsaw and heavy equipment so I didn't have the opportunity to test everything I wanted to, like the shorter antenna. The long antenna gave excellent reception and was only slightly in the way. Since the radio is so much smaller than say a KG 935, it was really convenient to have on me at all times. The gator clip is outstanding, it's not going to randomly fall off. I thought the TX Beep would be annoying, but it was very beneficial to my daughter who was using it from the house. If you don't have much experience with a handheld you can short stroke the PTT key, but with the beep it lets you know when you've keyed and let go. I found programing to be simple and enjoyable with the manual. I think it is strange that all channels are pre set to narrow band, but easily switched. My only complaint after a day of use in the woods is when I set a DCS code, you lose that channel without a code. For instance if you save channel 18 with a privacy code, you cannot also have channel 18 with no codes to communicate with others without a code. I could be missing something, but that is my experience with it so far. If the stubby antenna works nearly as good as the larger antenna, it would be very convenient to have on you at all times without getting in the way at all. Battery life still says 100 after having on for 5 hours and using occasionally. Very satisfied with the initial run, time will tell.

I passed the Technician test Thursday and I'm just waiting for the FCC. I need a good dual-band antenna for the top of my small car. It needs to be NMO compatible so I can use the mag mount I already have and not more than about 2 feet tall. For now, I'm going to use it with a Baofeng AR-5RM while I ponder exactly what I want as a permanent installation. So, what do you recommend?

I think that's what I was looking for.

I understand your confusion. The FCC messed up. Once upon a time companies were allowed to make dual service radios (FRS and GMRS) but now the regulations do not allow authorization of the combination. At that time there were FRS channels and GMRS channels. 95.1761(d) (d) Effective December 27, 2017, the Commission will no longer issue a grant of equipment authorization for hand-held portable unit transmitter types under both this subpart (GMRS) and subpart B of this part (FRS).

I used mine all day today whilst off-roading.

Unfortunately that one isn’t recommended for use with a mag mount.

The SBB2 is my favorite mobile dual band antenna. But after me snapping one off on the garage door and my wife snapping one off when she raised the tailgate of my van when I had the thing laid down, I didn't want to throw down for a third one. I run this one now, which has a spring. I've been happy with it. https://www.dxengineering.com/parts/dmn-az504sp?seid=dxese1&gclid=EAIaIQobChMIh6jprOKWigMV5CpECB0VjS8uEAQYASABEgKQNfD_BwE

So far, I like the Alinco. It’s very convenient in that all I have to do is program it and I have only a few buttons to push and talk. However, with that (for those who don’t know) this radio is not manually programmable. Must be programmed on a computer. Which stinks to an extent… if you have to put in a repeater or such on the spot. I haven’t explored much with it as far as other features. I don’t think it’s feature rich in many respects and it’s a pretty straightforward radio. I have performed checks while out and it hits repeaters that the Beofengs weren’t. So that’s impressive. Overall, I’m happy with it other than the programming issue and they packed it in the box a certain way and the antenna is bent… which plays on my “perfection complex”. But I’m not perfect either…

congratulations! Take a look at the comet sbb-2: https://www.dxengineering.com/parts/cma-sbb-2nmo

Uh...have you looked at the map. There's loads of repeaters around there. Three should be easily reachable. Depending where in St. Clair county Mayville 550 or Macomb 675. Actually there's two in Mayville the 600 which used to be Michigamme network and the 550. Usually plenty of traffic on the Mayville and Macomb. Throw your call out someone will respond.

They are effectively the same radio. Depending on how you order depends on the antenna(s) shipped with the unit. Upon powering up, there's a sequence of buttons that can be pressed to change it from gmrs to ham or 'normal' (open to all). I leave mine gmrs, as the whole point is to be able to hand a channelized radio to someone for use, not to accidentally have them dial up some unknown freq.

Like Mr. Shannon said, No! Anyone not directly related to you must have their own license. One way to have members of a non-profit organization operate under one license is to apply for a Business Band License, but that's more headaches than it worth. It's possible, even if you have to use a community repeater, which mean your group would be assigned tone. These days getting a repeater and radios plus the license and repeater pair would run over $5,000.00 easy. Nah, you might as well ask each member to apply their own GMRS license and take it from there. It cheaper and each member can share their license with their families.

Hey All! WRYL951, Tyler, here! What does everyone think about an improptu GMRS "net" for the Hollidays? Seeing as were currently 20 members strong so far, Why not reach out and share some radio joy as we move through the final month of 2024? Glad to be here, and Happy Hollidays to all whatever your Tradition may be! Maybe give a quick reply and let everyone know what repeaters youre able to hit the best, and maybe some others that you can touch but arent the best. Maybe we can find one we can all touch, that would be amazing!

I have listened to the ISS repeater many times with a $30 Baofeng. Antenna polarization helps.

Although the situation you describe certainly does happen, verify your testing method. Often times voice is getting through the repeater but the person's test method is faulty and they think they aren't getting through. The most common problem in this is the transmit radio and the receive radio being too close together creating desence on the receive radio essentially causing it to "go deaf" to the repeater.

Normally you'll be fine if you accidentally press the PTT without an antenna. But in rare cases...

Ordered a pack of the Baofengs mentioned in the OP. Tried one this morning on an HT and hit a repeater ~5 miles away through the woods. I'm sure the signal is poor compared with longer antennae, but still surprised it connected. Could be a nice option for campsites or road trips. At $9.66 for a four pack, may as well throw some in the bag.

They can use the phone on board. https://weather.com/news/news/2019-01-07-astronaut-accidentally-dials-911-space-station https://youtu.be/3L82DHQfcF8

I purchased a UV9G for a neighbor's birthday. We used our radios when we lose power. He is happy with it. We have used the radio in the snow and rain and it has held up well. Another friend just bought two of them to use for his family. He is happy with them. I think they are good radios for the price. I don't personally own one. I have several Wouxuns.

It flew directly over me today and I was going to try to get through the pileup but I got busy forgot.

I have talked to 2 people on the ISS and used the ISS repeater several times. It was surprisingly easy and only required a few watts. I didn't use any fancy hardware or software, just a zero-gain dual-band vertical antenna and a dual-band radio. I adjusted the frequency for Doppler manually, fairly easily, too. It's a lot of fun, but I got bored waiting for comms windows, and gave up on it after awhile.

I have the GT-3WP which is the ham version. It's a good radio for the price. Had it out in the rain several times. My coworker has UV-9Gs and he likes them as well.

I can't imagine having enough people to do this. Around here I can't even get anyone to answer calls to the repeaters so I can verify I have my radio programmed correctly.

Great choice as you can't go wrong with RT Systems software. I have it for all my amateur radio equipment and never had any issues.

Both the same radio. I believe the only difference in the package is what antenna it comes with. GMRS tuned or Ham tuned. Both radios can be changed to either GMRS, Ham or Normal which is unlocked.

I really don't want to see you leave. I think you're a nice guy and you contribute a lot here. I think you're just taking my comments and the comments of others entirely too serious. Steve and I disagreed on something. We had a conversation about it. Nobody got offended because the other guy had a different opinion. That's just normally how adults do it.

I'll tell you want i think. In the end, no one gives a damn what the rules say, they do what they want or think they can get away with. Even the people who don't publicly admit it due to work, or position in the community, etc., fall into this category. I think the entire conversation is theater, boredom or both. Carry on.

He is a master baiter.

Wait, what AI engine created that post? Or where did it get copied and pasted from? Training ground for engineers, and emergency responders? The engineers thing is laughable at best, and I have NEVER even heard of ham radio being a contributing factor in someone becoming a cop or fire fighter. Now I have seen MANY a wacker that couldn't get into public safety for various reasons end up with a ham license. Never the other way around. Others are welcome to comment here, if they have ever heard such a thing, but I'm not gonna hold out much hope. The engineer's thing. Most new hams are not even good appliance operators. They care little about the quality of their equipment (Baofengs) and for a long time they were getting their license for other reasons like joining a SAR / CERT group and it was sort of a requirement for those groups. The continued push that ham radio is for emergency communications promises the ARRL a new batch of members / license holders every time there is some significant incident that other types of communications fail and the otherwise uninformed general public see the statement that "Ham Radio Saves Lives" and go see about getting licensed. Some get as far as finding out about the tests and that sends them to GMRS or drives them off all together. A few go the full route and get licensed, buy a radio and listen to it for a month or so and put it in a closet. VERY few become anything resembling active in the hobby. Fostering innovation? Gonna ask, what innovative thing that had made a significant contribution to radio communications has come out of ham radio in the last 50 years? I just had this 'argument' with a bunch of backwards thinking hams that were certain that StarLink was going to be the end of EMCOMM (emergency communications) with regards to ham radio. And if they don't figure out how to adopt it and other newer technologies, then yes, it might do just that. The whole ad-hoc, no infrastructure, radio to radio communications thing is great if two things are present. First is the distances are short. No one is going to be of any assistance with a flood or tornado if they are on the other side of the country. Those sorts of things are localized. The communications need to be localized as well. FEMA and other state EMA agencies have all but completely gotten away form HF as a resource, because it's of limited use. They bring in trailer mounted towers and VHF/UHF/800 equipment to restore communications for public safety. So if you have no infrastructure, the other thing you need is enough people to bridge the gap in coverage between where you are and where the people are you need to communicate with. That requires operators in specific places to relay traffic from you to the other party. Ham radio was in the past fairly active most places. Now that activity is significantly lower. And even if those people are in the right locations, are they going to be willing to participate and pass traffic.

Yes - my thought is that within a few weeks this thread will be 10 pages long with nothing more than a bunch of verbal-masturbation and social-defects trying to prove to everyone how smart they think they are.. and, nothing will come of it.. then, a few months later someone will come and ask the same thing again and it will start all over again.

No.

Oh thank goodness some pioneering spirit came along and thought of this topic. It's about time! I'm shocked. SHOCKED. that no one's ever discussed this before! Now, I have some new and unique thoughts on Linked Repeaters I'd like to share with the class

No, we are unlikely to settle this debate, regardless of how many times the question is asked. But there are lots of other posts about it. Line A is one reason. 12 million people live above Line A and thus are prohibited from using 19. Second, GMRS really isn’t used by most people to “call out on”. It’s primarily for use between people who know each other while pursuing other activities. It works very well for that. Don’t worry, you didn’t start the debate. It just has some dormant periods. Welcome to the forum!

Thanks for posting. I was just thinking about programming some MURS channels on my H8 GMRS running in unlocked mode. I mostly want to listen but it would be nice to know I could transmit if needed.

Hey folks... I have been seeing a lot of antenna related posts lately. Some info I have read lead me to create this post. I want to try to help people understand design types and how antenna SWR and Gain are impacted. I am not going to get too technical, because I don't want new people to feel lost or leave with more questions than answers. As an FYI, while the concepts apply to all antenna types, I will be focusing on vertical antennas, such as what we use on our vehicles. First, lets discuss basic antenna standards and why antenna length matters. The best way to describe how basic antenna length is relevant, is by comparing an antenna to a speaker. Pretty much everyone understands that a speaker vibrates to make noise. We also understand that small speakers do a better job at making very high frequency sounds (tweeters) and really big speakers are better for making very low frequency sounds (like a sub-woofer). Antennas are the same way. The lower in frequency, the bigger (or longer) the antenna. The reason for this is because, like a speaker, antennas resonate (or vibrate) the best at one very specific frequency. As you go higher or lower in frequency, you are moving away from the antennas resonant frequency This becomes important for several reasons. One is because the closer the antenna's resonate frequency is to the frequency you want to transmit on or receive on, the more range and fidelity you get. Another reason is because the energy that gets sent to the antenna must go somewhere. If the antenna is not at the correct length to vibrate at the desired frequency, that energy gets wasted by being "reflected" back into transmitters, as well as desensitizing receivers. Any energy that gets reflected back into the radio is typically identified by the Standing Wave Ratio (SWR) or the ratio of transmitted (forward) energy vs. reflected (reverse) energy. Here is why we watch SWR. If your transmitter is putting out 50 watts, and your meter says you have an SWR of 1.7:1, that means only 45 watts of energy leaves the antenna and 5 watts goes back into the transmitter. A high SWR not only causes power loss, but it also generates heat as well as applying reverse electrical energy to the parts. If enough of a percentage gets reflected back into the transmitter, it breaks. It is very well documented that with the current technology we have, the threshold is an SWR of about 3.0:1. So, now that we understand, on a very basic level, why antennas need to be a specific length to work the best, and also have a basic understanding of what SWR is, lets discuss antenna design. So, what's the standard? An isotropic antenna. This is a theoretical antenna that radiates equally in all directions with the same intensity. Basically, a perfect sphere. The antenna is said to have a power gain of 1 in the spherical space all around it and has an efficiency of 100%. The concept of an isotropic antenna is often used as a reference antenna for the antenna gain. What is antenna gain? Glad you asked! There is a lot of science behind that... so I am not going to bore you with science. Instead, lets talk about food! Everyone loves food and its pretty easy to understand. So, the concept of gain is this... you only have 100% of your energy available. There is no such thing as an antenna magically giving you more power. You know the perfect sphere radiation pattern mentioned earlier... well in the real world, the closet we have ever come to creating that, actually looks more like a doughnut. Imagine a perfect doughnut. Sounds yummy right? Well, you only have 100% of the doughnut. What do you do if you want the doughnut to be wider, say... to fill a box better from side to side? I mean, its a whole doughnut. Easy... you squish it from the top and bottom. Then the doughnut gets shorter from top to bottom, but the food has to go somewhere. So, it spreads out wider or "gains" width in sacrifice of height. Well the more you squeeze from the top and bottom, the wider it gets, but loses height until the doughnut is perfectly flat and the 100% of the doughnut as been spread as far as possible. The squished doughnut thing makes sense, right? Antennas that have "gain" do the same thing. They squish the radio energy doughnut, forcing it to be wider to cover more distance, but at the sacrifice of signal height. This means that while you can transmit and receive further side to side, you lose elevation. Lets imagine you are at the bottom of a hill and your buddy is at the top. If you don't squish the doughnut, he can hear you because the doughnut is at its full height. But if you squish the doughnut, people further away at your level will now hear you, but your buddy who is very close at the top of the hill will not. So, gain has a trade-off. If you live in a hilly or mountainous area, you may want to avoid high gain antennas, so as your elevation changes, you are less likely to lose touch with someone. Compare that to being on the water, in flat(ish) desert or talking aircraft to aircraft, you may want a very high gain antenna, because there will be no significant elevation differences. Now, from here, we could talk about the benefits of stacked phase element antennas, takeoff angles and a bunch of other stuff. However, unless you have a more advanced understanding of antenna propagation and design, and plan on getting into some high-tech stuff, it will likely cause more confusion. Not to mention, for what we are doing... those items are almost not relevant when it comes to helping you pick the correct antenna for your application. So, let talk about how gain and SWR can really be confusing and how numbers can trick you into making a mistake. Remember when we discussed antennas needing to be a specific length to resonate at the desired frequency? Well, many high gain designs cause the antenna to properly resonate at only small segments of the frequency spectrum. Basically, what these means is (as an example) instead of being resonant and having good SWR across 100 megahertz, the antenna design may cause the antenna to only be resonant and have proper SWR at 10 small groups of frequencies inside that same 100 megahertz range. Watch the two videos linked below for a better understanding. In the first video, I have a Diamond NR7900A mobile antenna. It has 3.7db gain on VHF in the 140MHz-160MHz range, and 6.4db gain on UHF in the range of about 440MHz-500MHz. You will see that while measuring the SWR (or the antenna and cable resonance) you will see that in the VHF segment, the SWR varies somewhat quickly, but only has a single swing, from high to low and back to high inside of about 20MHz. When I switch to UHF and test the higher gain portion of the antenna, you will see the the SWR bounce up and down a few times as I sweep about 30MHz. This shows that the higher the gain, the more the antenna design may actually make it so the antenna is not usable on your desired frequency. Of course this all varies by brand and model, but the principle is still universally true. https://www.youtube.com/watch?v=Rh6w46VM_Ng Now, in this second video, we are looking at a UHF 1/4 wave antenna. This antenna is considered to have a gain factor of 1, and any number times 1 equals itself... so effectively, no gain. You can see that we sweep over 50MHz and while the SWR wavers a little, the SWR is stable compared to the high gain antenna and 100% safely usable through the whole spectrum, never going over 1.4:1 from 440MHz to 470MHz. Again, reinforcing the idea that the closer the antenna is to the desired resonant frequency and the less you squish the doughnut, the broader the usable frequency range will be, the broader the geographical coverage will be, the less risk of losing power due to poor SWR, and less risk of damaging your transmitter. https://www.youtube.com/watch?v=P5GiPLzVzbg So, to wrap this up, I want to discuss antenna tuning. Some antennas may need to be cut to the proper length to resonate on the desired frequencies. This is typically done with antennas that either have no loading coils (1/4, 5/8, 1/2, 7/8 wave length antennas for example) as well as some bottom loaded antennas. A bottom loaded antenna is an antenna that has a whip that is not the correct physical length to be resonant on a desired frequency, but the coil of wire on the bottom makes the antenna electrically the correct length. General speaking, for VHF and UHF, I recommend staying away from antennas with coils in them if they have been physically shortened for looks/clearance reasons. These antenna work, but are not very good performers. That said, there are some antennas that are "pre-tuned" at the factory to perform correctly in the indicated frequency range. These are typically gain antennas that have a collection of coils and capacitors on the antenna to help create the phasing and properly stack the elements. These are referred to as LC networked antennas. If you have an antenna that has stacked phasing and/or LC networks and you can't get a good SWR... unless the manufacturer provides directions on how to properly do so, do NOT trim the antenna to try to achieve the proper resonance, as you will only damage the antenna. The coils, capacitors and whip elements are precisely cut to work together. If you do not get a good SWR, either you need to pick a new location to install the antenna, the antenna is not properly grounded or the antenna is damage and should be replaced. If you do trim a stacked phasing and/or LC network antenna, in most occasions, the antenna never gets to the proper length regardless of how much you cut the whip and you end up tossing the antenna in the trash. If you get it tuned to a target frequency, it's usable bandwidth will be so small that the antenna will not have any real value. I have seen some people try to tune high-gain antennas, get them tuned to about 1.7:1 or even 1.9:1 and as soon as they tune 10KHz in one direction or another the SWR skyrockets. I hope this helps with some of the antenna questions.

Marc, I applaud the effort, but you've got the "gain" thing incorrect. Gain is a relative measure: something over the reference. And decibel is a logarithmic unit. "my antenna has 1db gain" translated to English means "intensity of the field created by my antenna is 1.26 times higher than the intensity of the field created by <what exactly???>". 0 dB = no gain over whatever reference you are using 1 dBi = 1 decibel over isotropic antenna ("i" is for isotropic) 1 dBd = 1 decibel over half-wave dipole ("d" is for dipole) Half-wave dipole has 2.15 dBi gain, that is 2.15 dB over isotropic antenna, and the intensity field is shaped like doughnut Quarter-wave monopole over ideal ground has 2.15 dBi gain, and the field is shaped like the upper half of the doughnut 1/2-wave and 1/4-wave antennas often called "no gain" or "unity gain" because they have 0 dBd gain (who might have thought...). Manufacturers and resellers may specify dBd or dBi. When they just specify dB it is better to assume that dBi is stated.