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I live in a draw, well below local average ground level. There are two repeaters I want to be able to use (because they're in the network my club uses). One is in the 440 band, thirty miles away but more than a thousand feet up in a pass, with a small mountain (a little lower than the repeater) directly between; the other, on 2m, is on a radio tower fifteen or so miles away, but with the ridge that forms one side of my draw blocking.

Short of installing my own repeater or antenna on a tower high enough to get over the surrounding terrain, is there a trick for hearing and being heard by either of these repeaters while at home? I have 8W of transmit power available on a 16" Nagoya antenna that replaced the original on my BaoFeng BF-F8HP.

Zeiss Ikon
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    Can you hear the repeaters? – Phil Frost - W8II Mar 27 '19 at 17:28
  • @PhilFrost-W8II I'm not certain. I'm pretty sure they can't hear me, but repeater traffic levels in general seem low enough I'm not sure whether I'm not hearing the repeater, or it's just not transmitting. Some repeaters I can hear send an ID periodically, some don't -- so again, I can't be sure. – Zeiss Ikon Mar 27 '19 at 17:30
  • A mountain in the way does not necessarily block desired signals. Google radio knife-edge refraction. Any reason why you can't try and hear the repeaters? – Mike Waters Mar 27 '19 at 18:33
  • I have tried, heard nothing -- can't tell whether that's because no one is talking, or because the signal is blocked. – Zeiss Ikon Mar 27 '19 at 18:58
  • Then why don't you try to key the repeaters? Just say "[callsign] testing". (And what is your callsign? It's not in your profile page. Mine is W0BTU.) – Mike Waters Mar 27 '19 at 19:19
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    @MikeWaters I'm aware of diffraction, but for 70cm (the one with the mountain) I'm pretty sure a mountain doesn't count as a "knife edge", and I'm sure a gentle ridge doesn't for 2m. – Zeiss Ikon Mar 27 '19 at 19:20
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    @MikeWaters I've tried, multiple times with each repeater, at 4W and 8W power level. No response. I'm KX4QP -- just got my call a week or so ago. – Zeiss Ikon Mar 27 '19 at 19:21
  • Let us continue this discussion in chat. – Mike Waters Mar 27 '19 at 19:30
  • Can you ask someone to transmit at a predetermined time? That way, you can know if you can't hear or it's just quiet. Can you move to a different location where you do have better access to the repeater and try from there? Hopefully you can leave your home and do a test from a better vantage point. That might also be the easiest way to ask someone to transmit at a specified time to assist your troubleshooting. – Aaron Apr 02 '19 at 21:15
  • You have said that you cannot place equipment at the locations which would help you to go over the obstacles, but is the terrain such that you could go around instead, or 1) is the mountain/ridge too long and/or 2) the land private, posted there as well? – Aaron Apr 02 '19 at 21:22
  • The higher we go in frequency, the harder it is go over an obstacle. But based on my 1980s 2m experiences and related things that I've read over the years, a high-gain Yagi array just might let you get into that 2m repeater. That's especially true as you raise the antenna height. – Mike Waters Apr 02 '19 at 21:52
  • I'm going to try Echolink before I spend money/build an array of yagis and mount them at treetop height. I asked this because I thought 2m was a practical communication system -- seemingly, it's only truly practical if your'e on a hilltop. – Zeiss Ikon Apr 03 '19 at 11:20
  • @ZeissIkon wrote "only truly practical if you're on a hilltop" ... or at least not in a hole. It sounds like your terrain is more severe than what most people encounter at home. I would be frustrated in your position too, especially since my interest in radio is largely for emergency backup, so I would consider relying on internet to be a straight-up deal sinker as a permanent solution, but maybe just for temporary troubleshooting or if I were doing radio just for fun. – Aaron Apr 03 '19 at 14:49
  • Can you use a different frequency to contact people on the other side of the mountain and ask them to transmit back on one of the 2 you're interested in? That could allow you to establish comms with them without internet and without leaving your home, and still allow you to test your receive appropriately and without internet use (and without them making changes to allow the internet access, though maybe that change could be a good thing to have anyway). – Aaron Apr 03 '19 at 14:51
  • The only transmit-capable unit I have at present is a BaoFeng HT with 2m and 70cm bands. I'm pretty confident at this point that I'm just in a blocked signal area. To clarify, I do have (rather good) contact with some repeaters from home (the mountain blocking one of my access points is only 3 miles away and has multiple repeaters on it) -- just not the ones my club uses for nets. – Zeiss Ikon Apr 03 '19 at 14:55

2 Answers2

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Reaching a repeater 30 miles (48 km) away with a mountain in between, with a handheld, sounds nearly impossible. Reaching a repeater 15 miles away with a ridge in the way with a handheld sounds very difficult.

You could experiment with several improvements:

  • A better omnidirectional antenna up high, like on the roof
  • A radio with more power, like a 50 W mobile rig
  • A directional antenna like a yagi
  • A passive repeater (a 1/2λ vertically-oriented conductor) on the ridge or mountain top
  • A repeater on the ridge or mountain top that is linked to the other repeater(s)
rclocher3
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    I've contacted the club, expecting a pointer to the networking management to check on the last possibility. Putting something either place isn't possible (posted land). More power is a possibility; the network crosslinks to 6m and 10m as well. – Zeiss Ikon Mar 27 '19 at 16:14
  • @ZeissIkon How about on your roof as he suggested? Better yet, a tower or mast? – Mike Waters Mar 27 '19 at 19:59
  • I'd love it if you can prove me wrong, but I'm guessing a passive repeater won't do much good at that distance. The other ideas seem like they're worth trying, especially the directional antenna. – mrog Mar 27 '19 at 22:37
  • @mrog By itself I can't imagine that a passive repeater would help much, but in combination with a better antenna and/or more power, it might be just enough. I just had an idea: the passive repeater could be a passive yagi, or two connected yagis... – rclocher3 Mar 28 '19 at 17:35
  • @rclocher3 That's a valid point. – mrog Mar 28 '19 at 20:57
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Regardless of where you live or what band you operate, the general rule is: "If you can't hear 'em, you can't work 'em." A secondary rule for repeaters is that if no one is there, it gets boring fast.

The first challenge is to listen for the repeaters. If you do, you are most of the way there. If not, verify that your rig is configured correctly by going near the repeater and listening. If you hear nothing, try transmitting your callsign and seeing if you can key the repeater. If you don't, step back and figure it out.

When you do hear the repeater, next determine where you can hear the repeater. Can you hear it from the top of the ridge? If yes, can you see the repeater and your QTH from the top of the ridge? Maybe you can estimate how tall an antenna support structure you would need to be in line-of-sight.

I don't know your terrain, but the first antenna I put up for my son was a vertical antenna in a tree. It included a counterpoise. Rather than screw it to a base, I pulled it up with a rope. It worked really well for repeaters.

I've been advised that if you decide to install a yagi for better gain, it should be mounted with the elements vertical rather than horizontal. Repeaters are usually vertically polarized, so the system gain is much high if the yagi is also vertically polarized.

cmm
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  • I've pretty firmly established by now that I can't key the repeaters I need for the club nets from my home. There's so little repeater traffic around here that I'm not at all sure I could or couldn't hear them, but I've also established that one has a thousand feet of mountain directly in the way, while the other has round 60 feet of hill above line of sight near each end of the path. – Zeiss Ikon Apr 02 '19 at 19:23
  • I don't know any trick. If you could have someone come to your QTH with a higher power rig and a yagi you could see if the extra gain would help. If you are near me I could help. I'm near Boston. – cmm Apr 02 '19 at 20:58
  • I'm in North Carolina, north of Winston Salem. :( – Zeiss Ikon Apr 03 '19 at 11:17