LeoG

Well I have two repeaters in my area that I can reach that are on mountain tops. One is 22 miles away and the other is 17 miles away (50 watts). And my little 4 watt HTs with its OEM antenna reach both of them fine and I can hear myself pretty good with them. Some static but there is a good amount of quieting. And of course these are professional, likely commercial repeaters that costs 10s of thousands to put up. But the HTs do reach them. So I do really think it's foliage that is killing me off in my particular situation. The fact that a nearly ground level antenna goes as far as my antenna up 38' likely tells you that it's getting blocked by the same things. When I had it down on the ground I was using RG58/U and it still made it the same distance as using LMR400 with the antenna up 38'. Both coaxes are 50' long.

I was doing some Radio Mobile calculations and man oh man I wish. I had to downgrade the parameters severely to get my real life results. My real specs are 6.25 watts out, 7.2dBi gain antenna at 12 meters high, 2db loss (probably less) with a HT radio receiver with a .25uV sensitivity at a height of 1 meter. What I had to put in to get my real life results was much different. 1 watt out from the transmitter, 7.2dBi gain antenna at 1 meter high, 2dB loss and a HT receiver with a .75uV sensitivity. Either something isn't right or tree leaves really hamper the single very dramatically Here is what comes out with the real specs And here are the results that pretty closely resemble my results Lots of trees. I put the antenna on the back building in orange. I don't think I could get it high enough to get over the trees successfully. Probably need a tower 60-80'

Well I took advantage of the small bit of height I could gain. Looked to be about 16" Who knows, maybe it'll peak over the trees LOL. That was a joke son. I doubt it'll do anything.

Well no joy for me. I got the antenna up and it showed 1.02 for SWR while outputting 6.58 watts off the repeater. Apparently it's still not high enough. Signal drops off at nearly the same point as you go towards my house. I'm still below the tree line which I assume is the main issue. Probably work better in the winter. I drove around and north of me is the sweet spot, 3.69 miles which was barely audible though the static. Using the OEM antennas which aren't great, got a pair of Smiley Rubber Duck antennas coming but they won't be here for a week. I don't think they'll make any significant difference. It seems to be about 90% of the Nagoya 771G of what I've watched on some videos. But likely I will take it down and put it on my house so I can use it as a local area repeater and extend the range of the HTs some. I don't think I have a real option to get it up significantly higher. I think in the shop area it would need to go up another 15-20 feet. I can probably get another 2' higher with what I have.

Well the LMR400 came in. Not exactly bendy is it? Back in my CB days I was use to using RG8 which probably isn't quite as thick but close. But at least that seemed flexible. How small of a radius can I put on this? Anyone care to gander a guess? It's the real stuff, Times MIcrowaves Systems.

LOL. Please don't make me go there....

Ya, I'll say. By the time I was done I had 7-8 tabs open which included some of the rules I had to look up in order to be truthful in signing my application. Wasn't exactly hard, but it really could be put all on one page in CORES.

The FCC must be wrong

I am assuming he means you aren't getting more actual "watts" from gain which is true. That's why it's called "Effective" Radiated Power and not True Radiated Power.

Gain does not increase power would be correct. Gain does increase where the power goes. Zero gain is an antenna that radiates equally in a 360º sphere. Most antennas don't do that. An "Omni directional" antenna is really a lie, but in a good way. It still radiates in a horizontal circle (approx) but the beam of energy radiating from the antenna is cut off on the top and bottom so that power is all included in a beam that is 20 or 30 or whatever degrees in the vertical thereby increasing the effective power in that area. You aren't wasting it going straight up or down. It is being put to better use in the horizontal plane that it will be received in "effectively" giving you the result of more radiated watts. Gain doesn't multiply your radiated power, it directs it to a more useful area. Better?

I am running 50' of RG8/U coax right now. It's all I have until the good stuff gets here probably today. And I've heard that low power can make it harder for the meter to do it's job properly. HT says 4-4.5 watts and the repeater says 6.4 watts. Both falling into that low power category.

I have the Retevis MA-09 antenna and so far the SWR has been 1.01 on both my HT and RT97S at both frequencies 462 and 467Mhz GMRS bands. Not exactly sure how they accomplish this but I've checked on many of my HT's and the repeater in several different antenna placements.

Well that's a reasonable explanation. I'm going to see if I can get an extra 10' mast attached to the existing mast and get more height out of it on the roof. Maybe I'll get 35-37' off the ground.

Well that was disappointing. I went over to the shop and put the antenna on a makeshift mast, a 16' board and raised it up on the same bollard and now I can't get reception from the repeater from the same areas near my home. I'm sure the metal building right next to the antenna has something to do with it LOL The angle of the building does allow the signal to get to my house. Surprising it worked better nearly on the ground. Coax should be coming tomorrow. Maybe I'll get it up on the mast.

Flat lander.... Pretty hilly around here. Thanks.

Well color me impressed. I did a very jerry rig on the Retevis MA-09 antenna just for receiving even thought I did transmit a bit. My 1st try was with my mobile antenna on the roof 26' off the ground. It made it 1.3 miles before it quit. The 2nd try with the new antenna only 3' off the ground I was able to make it about 100' before my house 2 miles. Only because the house is on a hill. And it's only about 15' down from the top of the hill. I was able to hit the repeater with the TD-H3 (4 watts) with the OEM antenna which isn't that great. So I'm still using the RG58/U (50') so effective radiating power is about 11.8 watts which is a far cry from the LMR400 that will be on the system when I set it up for real, 24.5 EFP and the antenna will be 30+ feet off the ground.

I have a clothes line pole in my backyard. The coax might be a killer. Have to look up flagpole pricing. The shop height is 26' to the top of the roof and I have 4-5' above that for now.

That's a nice calculator. You have to do it in 2 steps to figure it out. Since my actual cable isn't listed, RG58/U, I used the Belden 8240. Using that cable gave me an effective output of 11.8 watts vs 24.5 with the LMR. Quite the difference. Thanks for the calculator.

That thing is up there. Not sure if I could get away with that. It's not my building, just a lifetime renter. And I don't think I'd want it up that high at the house. I can dream though, can't I?

Maybe this would help https://www.noisemeters.com/apps/db-calculator/

Right now what was sent to me is RG8/U with the kit I got and I'm waiting on my LMR400 before I actually put the antenna in the air on a semi permanent basis. I have two spots it might go 2 miles from each other. Want to find which one will work best for me. I guess the antenna gain is almost eliminated by the RG8 coax run.

That sound pretty nice. So 50w transmitter, 50' LMR400 antenna with a gain of 9?

According to Retevis I have the MA-09 antenna https://www.retevis.com/ma09-high-gain-gmrs-omni-directional-base-antenna-us

I found this calculator searching around the internet. The only thing is minimum baseline is LMR-400 cable. I was hoping it would go down to RG58 so you could make comparisons. https://www.antennas.ca/calc_ERP.htm My little system with 6.4 watts out, 50' LMR400 to an antenna with 7.2dBi of gain radiates and ERP of 24.5 watts.

I got the antenna today that was included in the repeater kit I bought. I have no idea what model number it is. It is a fiberglass version. I did pose the question to Retevis about the model number. I did some limited testing with it. I used a squeeze clamp and attached it to one of the boxes on my truck. SWR was nearly perfect at 1.01. I was able to put 6.4 watts into the antenna from my repeater. I took a walk about and got about 5000 ft from the house. Felt like more . I needed to go one more block to get to 1.3 miles which was where my other test with my mobile antenna dropped out. I have all confidence that it would have made it. But the situation was much different. The antenna wasn't 30 feet in the air like the mobile antenna was. It was 6' off the ground and the 1st thing it had to contend with is a house wrapped in aluminum siding and then a small hill. Much better antenna, obviously. So soon I'll put it on the shop and see what happens. If I'm not happy it'll go on the house so I can have the strong signal in my neighborhood.