Blaise

Oh absolutely, that's fair, stuff gets in the way. To antennae 6 feet off the ground, the horizon is roughly 3.1 miles away, so the maximum possible range the two of them can communicate at LOS is just over 6 miles, and obstacles between normally make it much less. But the argument rarely comes from that perspective, or at least not until someone pushes back on the "all things being equal" phrase that accompanies the original statement. I don't know, it just seems unnecessarily aggressive and not really accurate as generally presented...

I'm still not following. I don't see how representation changes anything. Just representing field strength in an exponential way doesn't change the power at distance x. If I decrease your salary by only one order of magnitude, using the number 1 looks a lot smaller than saying I've taken 90% of your pay, but did I take any less? If a signal is still "lost in the noise" after a power increase, it would be *less* lost in the noise by the root of the increase in power, meaning the range still increased, you were just still too far away, right?

> VHF and UFH are primarily line-of-sight. The signal essentially propagates until it runs into something (trees, horizon, big warehouse). But the amount of those obstacles that you can propogate through or reflect around still increases with the root of the power increase, right? I understand that completely blocking a signal is completely blocking a signal, of course, you can't go through mountains etc, but every attenuating material will still allow propogation to *some* depth, so if you increase power it will come out the other side of relatively more stuff than before, no?

I don't see the problem. Don't you want to keep them toasty warm?!?!? I mean, it's not like it's ionizing radiation...

I really don't understand that this keeps getting repeated over and over in GMRS-land. I'm new, so maybe I need to be schooled, but I've been reading stacks of antenna resources, and I started out with an engineer's education in fields and waves theory, and I just don't get this point! According to everything I understand, rf signal strength, all other things being equal, follows the same inverse square law that all electromagnetic fields do. This means that the distance at which signal strength drops off to unreadable levels increases proportional to the square root of any increase in power. So on a direct line between two antenna, assuming proportions of open air, obstructions, reflections, etc remain constant, doubling the power of a transmission provides more than 40% more range, quadrupling it provides twice the range, etc. Now, I can certainly understand providing a caution to new users that range isn't proportional to radiated power, because that's an easy mistake to make that will confuse a lot of newbs, but saying things like "Going from 5 watts to 8 watts is a relatively small increase in transmitted signal" that produces "very little difference in signal performance, all things being equal" when in fact a 60% increase in transmitted power results in more than 25% increased range, all things being equal, seems at best sloppy and at worst disingenuous. And people repeating it constantly across an en entire community seems... well, I won't say religious, but at least dogmatically ideological, anyway... What am I missing?

I just posted a work in progress last week that might help:

The difference being, I suppose, that I actually acknowledge the need...

Hey folks, I've been distracted from my antenna studies by a more immediate need to build practical, interoperable systems for my family, and I've discovered that it's not nearly as simple or rational a process as I originally imagined. I started using prepper resources to grab info on various radio services just because I'm a packrat, but when I discovered that while most manufacturers make an effort to comply with the rules of channelized services, you explicitly can't trust manufacturers to agree on code values for CTCSS and DCS, this turned into a more serious project. It turns out that when you start trying to get your kid's Retevis walkies, your Motorola talkabouts, an FRS-based intercom system, two different mobile units and a handful of Baofengs (kept for emergencies) to all interoperate at more than a basic level, you spiral down a nigh inescapable rabbit hole! Anyway, I'm attaching a spreadsheet I've been working on (mostly of stuff stolen from across the intarwebs, but some hand-transcribed from manuals or Amazon product photos). The first sheet is a frequency-ordered list of channels for FRS/GMRS, CB, and Marine bands (which I actually needed) plus a whole bunch of other frequencies in other services probably only interesting in an emergency (which I just grabbed because I'm a packrat). The second and third sheets are lists of CTCSS and DCS codes for different radios from different manufacturers. The frequency list is at least of interest because seeing where the "channels" actually lie in a band is a bit eye-opening, but probably of no interest to anyone experienced. However, the CTCSS/DSC code charts are super useful at least to me, and I hope useful to others! In any event, I'd love it if anyone interested would check my work for errors, fill in gaps, or find new code lists to add! (Did I mention I'm a packrat?) Common_Frequencies.xlsx

I've been reading about antennae rather a lot lately to try to understand this exact issue. I assure you I believe myself to be nothing remotely like well informed on this topic, but from what I'm reading, it seems like this has multiple possible solutions: If you separated the two antennae with a metal sheet about 5 degrees wide to each antenna, you would have a dead spot on a narrow line (which might be made up for at distance by reflection/diffraction), but the bulk of the transmitted energy would miss the receiving antenna, and lessen or eliminate the problem. If you mounted the two antenna colinearly one above the other, maybe also with a metal disc separating them, you could solve the problem similarly with no dead spot at all. Please help me understand how I am wrong! (I assume I'm wrong, since no one else said it...)

Yes, I thought I made it clear I understood that by starting with "Now I realize that transmission power is less important to range in this band than antenna placement, gain, etc., but..."

I've read 'til my head aches, but still can't find an answer. Can someone set me straight? I'm trying to spec a base-station, and I'm looking at the '50 Watt' requirement. As near as I can tell, virtually none of the commercially available GMRS transmitters really output 50 watts. It's usually somewhere between 45 and 48, from what I see. But even if they *did*, antenna cable and connector losses seem like they're going to eat a minimum of 10% of your power, even over fairly short runs, so really, there's no hope of ever transmitting anywhere *near* the 50 watt limit, and realistically you'll be closer to 40 watts. Now I realize that transmission power is less important to range in this band than antenna placement, gain, etc., but all other variables being equal, if I'm not mistaken, transmitting with 25% more power is going to get you as much as 11% more range and 25% more coverage area. That's a lot more than nothing! Is this just a loss GMRS operators accept, or is there more to it? Are folks using amps to bump their unit's output power up over 50 watts to make up for losses? Is there a trick to this that I'm missing?

It worked a treat on mine. So much more convenient and usable. And I can listen to marine band as I drive up and down the Hudson Valley!

Well, I think it's pretty cool. I got my wife and I a pair of Motorola T801s for a cruise we took in southern Europe, and being able to text with each other in five different countries without having to buy phone service was actually phenomenal. We've used them camping when out of cell/wifi contact for significant time, too. The best part? I did all the pairing and programming, and then I just had to show her how to turn it on and hang it on the back of her bag. All the rest was on the phone that's already glued to her hand anyway! (It *was* challenging to deal with her frustration with not having perfect, 100% connection, but it still got the job done)

I already have a nanoVNA v4. I needed it to sort out issues with my car antennae. Now I'm trying to figure out antenna placement for a base station, along with how it will interact with nearby antennae, and potentially buying a repeater (and maybe building a mobile one from HT's). It turns out that the number and complexity of the questions you need answered increases exponentially with the number of things you are trying to do!

Thanks, folks. I've got The ARRL Antenna Book, 23rd Edition (all 1000 pages!) and Reflections III. Looks like about three months of reading. Well, I asked for it!?

So I've been building a huge list of questions about how antenna layouts might work, and I've realized that onesie-twosie answers are always going to leave me wondering about the next thing, and annoy the folks I pester, so what I really need to do is go back to school. Anyone have recommendations on how to teach myself to fish in the sea of antenna theory and practice?

Wait. This is a thing?!?!? How would that work? Do you stick it out the top, off the side, or what?

WHATISGOINGONHEREIDONTUNDERSTAND

There once was a man named Roger Beep He got accosted by a radio creep Told him to leave, like a good little sheep 'Cause his presence made the weenies weep!

this message has been disregarded

I literally just got off a cruise (Royal Caribbean). The boarding security took out my GMRS HT's, turned them on and off to make sure they weren't bombs, and handed them back to me. I'm sure you'll be fine! FYI, Greece, Italy, and Montenegro apparently couldn't care less, either...

As far as *I* can see, it's turned into a ghost town...

I absolutely think we need more repeaters. I'd have put my own up already, but for the fact that once I got out the topo maps and found the best place within thirty mile, I discovered that a) the whole hilltop is owned by the water company, b) it has a large water tower on it that's already covered with ham repeaters, c) a local ham group convinced the water company to let them manage all antenna placement, and d) the ham group won't even discuss details like access/rent/maintenance/etc. unless you're a licenced ham who's joined their group. Instead, I'm trying to convince my wife to let me cut a hole in the tower ceiling of our victorian and place one up there. It'll likely get a quarter the range, but no one gets to tell me how things are going to work! As for the "don't be stupid, that's what ham is for" brigade, I'm ignoring them. My group wants to build reliable emergency comms for our region that *doesn't* require gatekeeper hams to use it. You'll never get churches, schools, and community centers to fund/maintain personnel to get and stay trained so they've always got a ham on staff, but a $35 license and a $100 HT is completely feasible. And that's not to mention being able to interoperate with actual community members for the price of $15 walkies from Walmart! A school or community member can keep a whole box of those things in the basement and just hand them out with ten minutes' instruction in an emergency, and they can even just listen in to repeater outputs to keep track of what's going on locally.

I don't think the concern here is that it's possible to find your address if someone is already targeting you by name. I think the concern is more that anyone who hears your call sign as you broadcast it over an area that could contain anywhere from dozens of people to hundreds of thousands of people could successfully target you based only on the call sign...

I think this is a business I need to look into....