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Theoretically radio waves would be radiated from a single point at exactly the same strength in all directions, forming a perfect sphere. That’s unity gain, or no real gain. However, in real life that sphere may take on other shapes, with more strength in a specific direction, or flattened at the top or bottom. But there’s just as much RF energy being emitted, so just like a water balloon, if you flatten it, the circumference becomes larger. That’s said to be gain in that direction. When there is gain in a direction, other directions suffer. Those may be directions that don’t matter. For instance, directly above or below the tower. The size and shape can be simulated using antenna simulation software or it may be estimated using past experience or it may be measured using a field strength meter. Most commercial antennas have some kind of published information.

Done all the time. Most good commercial ham radio offer cross band mode. Mine is always on the 2M repeater and a UHF simlplex channel on Low Power. Use it alot that way in the parks while camping.

Yes; you're understanding it correctly. For most purposes you probably wouldn't want something like that (and those are pretty idealized images anyway). It's just like a light bulb. If you just put a bulb on top of a pole with no reflector and no focusing, it's a small speck of light, but if you add a reflector you get brighter light (gain) in one direction at the cost of less light (or even no light) in other directions. That's what a parabolic antenna might do, but that's the kind of antenna that's only useful for certain applications, such as fixed point to fixed point communications. Most of us want something with a lot less directionality. Many repeater antennas or mobile antennas radiate a pattern that's like a flattened ball, wide outward horizontally, but with less gain vertically (both up and down).

That's exactly what it does and was designed for. Using different bands of course (VHF/UHF).

I absolutely agree with @WRUU653. Setting up a repeater just to reach another repeater using RF would probably cause severe interference. In order for your handheld signal to be received by your repeater and transmitted to the other repeater you would have to reverse your input and output frequencies, but then, the signal received from the other repeater would be instantly retransmitted to the other repeater, causing a feedback loop. GMRS Regulations simply do not permit a repeater to transmit on the “467 MHz Main Channel” input frequencies necessary to transmit through another repeater. Just set up a mobile radio in your house with a decent antenna on the roof and configured to hit the repeater.

This phenomena happens at the radio's "fringe" area, where of course everything, line of sight, objects in the way, etc. reduces the radio's range to have "hot spots" and "cold spots." It is why I added a short coax to my rooftop antenna's coax switch to my analog/DMR RD-5R HT so that I could sit in my "easy chair" and communicate consistently without sudden drop outs as I moved in my chair with the HT's original antenna. As I recall from my days studying radio theory, the superhet was invented to solve the problem of superregen radio's having poor selectivity; that is, an inability to clearly separate two signal on adjoining frequencies. I don't seem to recall that it added any increased sensitivity to the radio in and of itself; that is, the ability to receive the same signal at a further distance. So it just seems that your FRS radios just have a "hotter" front end design in their receivers than your Wouxun, or perhaps better squelch control. I'll look forward to what the radio super-nerds here have to say about this issue!

Simple half-wave dipole, 20 meters (~66 feet) above ground. Max gain 5.57dBi. Same antenna 100 meters (~330 feet) up. Max gain 7.36dBi FYI: EZNec Pro/2+ v7.0 is now a free download (the author has stopped providing updates). https://www.eznec.com/

Hello, I'm wondering if there is an easy way to create a customized map or view of the map that shows selected repeaters and their coverage footprint circles? i.e. I want to show coverage of the 5 nearest repeaters to me, etc. Does the site allow for that or is that something that could be added as a tool? It would be very useful to know coverage areas near you or for when traveling to a new area. Something similar to what I had-drew - attached. Thanks

Correct. If the repeater were active for "group a" and someone from "group b" keyed up as well, none of the other "group b" radios would hear the transmission.

There *are* repeaters (that work on GMRS) that won't do that, but *will* allow you to set up multiple CTCSS/DCS tones on the same frequency pair. That would allow you to use one tone for the farmer and one for the family and they wouldn't hear each other.

No. It’s configured with one set of frequencies.

Nope, you got it right. Some radios have a male center pin SMA connector (mostly the less expensive ones) and some have the a female connector on the radio. You must get the antenna that mates with the radio.

Posting my thoughts on the GMRS-PRO after little over 2 weeks of using it. Overall is not a bad handheld however if your group does not have the same device then text and location features won’t be useful, and without those features there’s plenty of better options from competitors at similar or lesser price point. This really feels like a half baked release priced too close to other well developed and reliable options. Pros: Programming from smartphone is very easy and convenient. The radio feels well built and durable. Included manual is surprisingly well written and useful to get started. Can be used as simplex repeater, compatible with any GMRS radio. The antenna is removable so it can be easily upgraded, they claim is glued in place but a simple twist and it came off. Cons: At this price point the K1 adapter ($22.49) should be included in the box, especially considering that cheaper radios come with more accessories and the connector was changed for no apparent reason other than to sell different accessories. Compass looses calibration constantly even when the radio is just sitting on a desk or flat surface. There should be an option to see both the channel name and frequency on the radio screen. App keeps constantly trying to pair with any Bluetooth device around even when already paired to a radio, making it hard to use. Battery life could use some improvement, about 10 hours with little/moderate use. BAOFENGTECH does not allow reviews that offer honest product feedback, instead of encouraging real reviews regardless of whether they're positive or negative they only seem to approve positive reviews that do not criticize their product.

You can vote an answer up or down along the left hand side, but that's the only way I know. I'm just glad it helped. Yes, you can have areas near tall towers with high gain antennas that are dead-zones. Some antennas even have an RF downward tilt to minimize that area. One way to do that is with slightly out of phase antennas in a colinear array. They're pretty fascinating. The harness running to the antennas has very slightly different lengths of feedline to create a delay to some of the antennas in the array, causing a downward shift in the radiated pattern. Fortunately, the manufacturer does all the math. Steve

For $80 more the Icom IC-2730 does dual band (70 cm and 2m) cross band repeat. This would all be so much easier and legal to do in amateur radio.

TYT TH-9800, $210.00. 50watt VHF, 40watt UHF radio. Does quad band (10m, 6m, 2m and 70cm but only two at a time) as well. Almost half the price of a KG-1000G+

Even easier (but definitely NOT LEGAL) would be to slap up something like a Comet GP6-NC (Dual band MURS/GMRS antenna) and MARS/CAP modify any number of dual band ham radio transceivers that do VHF/UHF cross-band repeat out of the box and run MURS HT's crossbanding to GMRS through the base station. One antenna, one radio and done. That's why I was questioning the legality of using a off the shelf, legal and certified MURS and GMRS radios doing the same basic thing using the headphone/mic repeater controller between them. You cold also install a UHF/VHF combiner and use one antenna. Isn't this basically what a Bluetooth headset would do, but on the MURS frequencies instead of Bluetooth? Would both radios would be legal for the band with a simple earphone/mic cable connecting the two?

It really is the best way to enjoy GMRS from your easy chair!

So, here’s how others have done it professionally using Vertex mobile radios. It’s a store and forward module that extends the range of a mobile radio to a handheld. Of course you would need to use a Vertex mobile radio, configured to communicate with the other repeater, but I’ve heard they’re available. Also, Midian makes these for other radios as well https://www.ameradio.com/product/512159/description.html If you like to tinker, you could probably do something similar and much less expensively using one of these: https://www.argentdata.com/catalog/product_info.php?products_id=98 However, thinking about this, it must do the forwarding on a different frequency (not band or service) than the mobile, otherwise you would simply end up with a time delayed feedback loop.

Range if he wants to use it more than 50 yards around the cabin. MURS should get a heck of a lot more range than Bluetooth. And another stupid question - A few posts above states: Would Bluetooth not violate this rule?

Okay I see where you're going now. How about a blue tooth enabled HT that is hooked to an external antenna that you can monitor without disturbing other people in the cabin? And for the record I don't think the question was stupid, I love thinking out of the box even if it's just for theoretical discussion...

So, how could a person legally design some kind of “range extender”? @markskjervehas the simplest solution; but I’m doubtful of the legality because of the cross-banding. It’s more than simply cross-banding; it’s going between two different services. The problem with the original idea is that two full duplex devices connected to each other form a feedback loop. But what if you use simplex GMRS (store and forward) on the end you’re trying to extend so you can be outside of the cabin?

Still would be considered a repeater. Not permitted and it wouldn't gain access to the second repeater OP wants to reach

I was thinking more along the lines (in OP's case) of having a nice GMRS base station at the cabin along side a MURS radio with a $40 HT style cross band repeater controller (https://www.amazon.com/Serounder-Repeater-Two-Way-Controller-Communication/dp/B07QXYJRBN) that connects between the earphone and mic plugs off Amazon. Then use a MURS HT for mobile use around the cabin back to GMRS.

There’s no doubt that a “true base station antenna and feedline” is better for a full time repeater, but I wouldn’t be so quick to declare “Well, that’s your issue.” The losses through 10 feet of LMR400 aren’t enough to cause this problem and a decent mobile antenna can be expected to transmit and receive just as far on a repeater as they do on a mobile radio. The O.P. really needs to rule out other things before investing money in hardline and a Laird antenna. He might spend quite a bit of money trying to build your concept of a repeater, only to find that his friends have a wrong setting somewhere. He already said this is a test setup; let’s help him get as much out of the test as possible before sending him back to the store. @WRMN374 Are your friends able to communicate when they get closer? Can you loan them your handheld radios and have them see how far away they can get before they no longer make contact? If it’s just a matter of range, then @gortex2 may be correct, that it’s a matter of not getting enough signal out, but if that is the case they should have no problem hearing you when they’re closer. Let’s take the repeater configuration out of the picture for just a second. If you clear the tones and use a simplex frequency can you contact your friends using one KG1000 as a mobile/base station from your location? I would make sure that you can do that before adding the complexity of a repeater. Where is your antenna and cookie sheet located? Is it up on the roof or on a mast outside or do you have it in the house? Notarubicon (@OffRoaderX) recently released a really good video that illustrates the value of a good antenna compared to adding more power that you might find interesting.

Now to start planning an attic antenna!

You could put your own backyard repeater up and link it to the network. https://www.retevis.com/rt97s-full-duplex-portable-gmrs-repeater-bundle-us

If you're looking to get some detailed info the below site has a lot to look at. It would be worth your time to check it out. Also people here that have been down this road before can supply good recommendations. http://www.repeater-builder.com/rbtip/index.html

I am cool with that, not sure if there are other arrangements with other users, anybody is welcomed to chime in on their thoughts or ideas on this.

I tried two different GMRS 9R's and both of them had reception problems. Transmitting was fine but when it came to receiving signals, they were deaf as a stump. I've never owned a UV-9G so I don't know if they have this problem or not. If you must have a radio with the IP67 rating, you might want to bite the bullet and buy a Wouxun KG-S88G.

Back in the early 80’s, I worked EMS in a small town. Our ambulance had a radio that was called “Pack-Rat”. We had the regular two way that was installed in the rig, and a handheld docked next to it. When you undocked the handheld it would use the rig radio as a repeater. So even when sub terrain, as long as the rig was on that property it would repeat all trans and rec to the handheld. It was awesome. Until the FCC banned it. Unfortunately I don’t recall the reasoning behind it, but we ended up with a crappy radio in the rig with no pack rat after.