krvw Posted April 9, 2020 Report Posted April 9, 2020 So, I started my personal GMRS and ham journey in January of this year for reasons that are not relevant here. Among my goals was to be able to have simplex RF comms with my wife at her office. (2.1 miles as the crow flies, through suburban northern Virginia. Small rolling hills, but plenty of RF interference along the way.) Frankly, I was disappointed by the limitations of HT<-->HT around here. I was lucky to make it 3/4 - 1 mile. Clearly, line of sight matters enormously. I got a simple j-pole antenna and tried that at home from my attic. (HOA issues.) Still HT to HT, but no luck. I got permission from the HOA to put up two 5 foot j-pole antennas and got them up yesterday. (See attached photo. Both are Ed Fong designs. One ham and one GMRS tuned.) Simultaneously, I got a 50 Watt (UHF) / 40 Watt (VHF) mobile radio. This morning, I ran a quick and informal series of quick tests with the mobile radio set up in the ham bands (70 cm and 2 m) as a cross-band repeater. (I use a 70 cm simplex channel to my home mobile, which then repeats it on 2 m out to my local repeater (W4AVA).) In short, VICTORY! The repeater connections had several flat spots for me. They're 99% gone now. I can trivially tx/rx to my wife's office location with 5 by 5 audio signal on a simplex connection. I know many folks here dismiss the Ed Fongs, but I have to say those reviews are not consistent with my experiences. In particular, the Warrenton GMRS repeater that is some 40 miles from here was completely out of range for me in the past. With the Fongs on the roof, I'm getting 5x5 signal reports consistently on that repeater -- which serves a vast footprint of NoVA and MD. YMMV. So, yeah, I'm pretty happy with where I am on my personal journey. Cheers, Ken van WykWRFC318 / K0RVW scottmckinney67, FfxCo15, Ian and 1 other 4 Quote
Logan5 Posted April 9, 2020 Report Posted April 9, 2020 That's fantastic, I would normally recommenced against locating a fiberglass antenna so close to gas chimney but good old PVC can more than handle it. my only other concern would be the metal chimney causing unwanted reflection, but if you have achieved your goal, no worry. I have wanted to try one of those Ed. Fongs, maybe now I build one. Quote
krvw Posted April 10, 2020 Author Report Posted April 10, 2020 That's fantastic, I would normally recommenced against locating a fiberglass antenna so close to gas chimney but good old PVC can more than handle it. my only other concern would be the metal chimney causing unwanted reflection, but if you have achieved your goal, no worry. I have wanted to try one of those Ed. Fongs, maybe now I build one.That is PVC (schedule 20). Also, the vent is 30 feet above the furnace area. Also, I had really no choice on that. If I want an outdoor antenna, this is the spot. Cheers, Ken Quote
rodro123 Posted April 11, 2020 Report Posted April 11, 2020 Nice job on the install looks good. krvw 1 Quote
axorlov Posted April 11, 2020 Report Posted April 11, 2020 Nice install! Too close to chimney and to each other for my taste, but I understand your HOA limitation. As mentioned before, Ed Fong's antenna requires RF choke. Your install looks like there is no metal mast or anything near the coax to couple with, and this is probably why your setup worked better than mine. Quote
berkinet Posted April 12, 2020 Report Posted April 12, 2020 Note. I obviously know nothing about your furnace. But, with modern high-efficiency furnaces, the exhaust gases are not very hot. In fact, a fan is usually required to use the exhaust fumes out the vent. So, if you do have a modern furnace, heat damage to the PVC is not likely to be an issue. Logan5 and Ian 2 Quote
krvw Posted April 13, 2020 Author Report Posted April 13, 2020 Nice install! Too close to chimney and to each other for my taste, but I understand your HOA limitation. As mentioned before, Ed Fong's antenna requires RF choke. Your install looks like there is no metal mast or anything near the coax to couple with, and this is probably why your setup worked better than mine. Thanks. The chimney is a furnace vent, and I had no choice on that. I only use one antenna at a time, so that proximity isn't something I'm worried about. Hadn't heard anything about an RF choke requirement on the Ed Fongs. Got more info? I'm able to consistently hit a GMRS repeater that is some 40 miles away. I can also _usually_ hit a 2m ham repeater that is 45-50 miles away. And, on the repeaters nearer to me, my signal is really solid. So yeah, I'm really happy with the results. Cheers, Ken Quote
BoxCar Posted April 13, 2020 Report Posted April 13, 2020 The Ed Fong antennas include the choke which is inside the PVC pipe. It's on his web site Ian 1 Quote
axorlov Posted April 14, 2020 Report Posted April 14, 2020 The Ed Fong antennas include the choke which is inside the PVC pipe. It's on his web siteI have Fong's antenna and mine does not have choke. Neither ferrites nor any coils or anything. Just a short piece of RG-174 to the connector. J-pole antennas, by nature, need RF choke of some sort. On UHF frequencies they are usually ferrite beads put over the coax. In my case, antenna was installed on the 10' steel mast, and it was very clear, that the coax couples with the mast. I had SWR swings from 9:1 when coax is dropped along the mast, to 3:1 when coax is pulled away from the mast. Since ferrite beads would cost me around $25, and I already had commercial BR-6140, I just put it up. I lost 2m capability, but I do not really care. Btw, BR-6140 still available at newegg for $35. Quote
FfxCo15 Posted April 14, 2020 Report Posted April 14, 2020 Nice setup! I'm in northern Virginia also (Fairfax) and may do something similar. I can hit the Warrenton and Alexandria repeaters from outside, but not inside. krvw 1 Quote
krvw Posted April 16, 2020 Author Report Posted April 16, 2020 Nice setup! I'm in northern Virginia also (Fairfax) and may do something similar. I can hit the Warrenton and Alexandria repeaters from outside, but not inside. I'm surprised you can't get the Alexandria repeater from Fairfax. (I'm assuming you mean Fairfax City?) I'm in Fairfax County in the Kingstowne vicinity. The repeater is now located near 7 corners, on top of a building near the intersection of Rt 7 and Rt 50. Guessing yours is a line of sight issue. I used this tool (https://www.scadacore.com/tools/rf-path/rf-line-of-sight/ to model the line-of-sight requirements for getting from my house to my wife's office. It showed me I needed to be 4-5 meters above ground, which my rooftop comfortably affords me. You might want to approximate the path from your house to the Alexandria repeater. Might be helpful, IMHO. Also, drywall matters. I was logged into a local RACES net one evening when I walked from my dining room out onto my deck. I was receiving audio the entire time, but the static disappeared when I went from indoors to outdoors. I was frankly shocked by how big a difference it made. That was one of my primary motivators to put the antenna on the roof. Glad I did! Cheers, Ken Quote
FfxCo15 Posted April 18, 2020 Report Posted April 18, 2020 In my case, I only have a 4w handheld I can use in the house, and it's a townhome community so I'm surprised I can hit it even outside with all the obstruction. I'm near the Wegmans in Fairfax, about 1 mile west of the city line. And yeah, almost 10 miles exactly from the Seven Corners location. I'm not sure why they haven't renamed the repeater in the listing. krvw 1 Quote
krvw Posted April 18, 2020 Author Report Posted April 18, 2020 I'm near the Wegmans in Fairfax, about 1 mile west of the city line. And yeah, almost 10 miles exactly from the Seven Corners location. Have you tried the Warrenton repeater also? They require permission, but they seem to grant it to any licensed GMRS operator. From my rooftop, I get a really clear signal on it. When I've gone west of here, I could get it on my handheld pretty well too. That repeater has a big footprint around NoVA. Quote
Ian Posted April 30, 2020 Report Posted April 30, 2020 Technically, Ventennas are another option that would fit your HOA needs. https://www.ventenna.com/ Still, unless you need more bands, you're in fine shape, and I've never heard ill spoken of the Ed Fong antennas, so... Quote
krvw Posted May 1, 2020 Author Report Posted May 1, 2020 Technically, Ventennas are another option that would fit your HOA needs. https://www.ventenna.com/ Still, unless you need more bands, you're in fine shape, and I've never heard ill spoken of the Ed Fong antennas, so...Thanks for that. I considered a ventenna, but when my HOA approved the j-poles... Search around this forum and you'll find plenty of discussion about Dr. Fong's antennae. One person referred to them as "no better than a dummy load". My main point was that my experiences with them have been positive. Being 1/2 wave, the propagation is largely toroidal, but that suits me. Perhaps I'll try a 5/8 wave at some point as well. Now that my antenna mounts are up, I can pretty quickly swap for different ones. Cheers, Ken Quote
berkinet Posted May 1, 2020 Report Posted May 1, 2020 ...Search around this forum and you'll find plenty of discussion about Dr. Fong's antennae. One person referred to them as "no better than a dummy load"... ...Being 1/2 wave, the propagation is largely toroidal, but that suits me. 2 points. #1. Consider that many people make their own "Ed Fong" antennas, some buy the kit, other's purchase a generic antenna for their desired band and still others order an antenna cut for a specific frequency. Thus, in addition to any issues about the effectiveness of the design, you have to consider all the other factors as well when evaluating user reports. #2. It is because of the toroidal propagation that the antenna achieves gain in a 360º pattern. Minimal energy wasted by being transmitted above or below the antenna's horizontal plane. krvw 1 Quote
krvw Posted May 1, 2020 Author Report Posted May 1, 2020 #1. Consider that many people make their own "Ed Fong" antennas, some buy the kit, other's purchase a generic antenna for their desired band and still others order an antenna cut for a specific frequency. Thus, in addition to any issues about the effectiveness of the design, you have to consider all the other factors as well when evaluating user reports. #2. It is because of the toroidal propagation that the antenna achieves gain in a 360º pattern. Minimal energy wasted by being transmitted above or below the antenna's horizontal plane. Both good points, for sure. My Ed Fong was built by him and sold via Better Safe Radio. I have both the ham and the GMRS tuned versions and both are performing quite well. I may well still try out a 5/8 wave like the Diamond X200a. My understanding of its propagation pattern is that it "flattens out and extends horizontally" the toroid pattern of a 1/2-wave. There are 2 popular repeaters in my area that are just at the edge of my coverage. I can get them at times and all static at other times. If a 5/8-wave gets me there, I'll be happy. I'll use the other Ed Fong for holiday trips when I want to set up a station in our residence. (We've ridden out about 5 hurricanes in the NC OBX area, for example. Having comms during those will be helpful.) That's not to disparage the Fong j-pole, though. Different designs, each with their pros and cons. I'm very happy with both my Ed Fongs. Cheers, Ken Quote
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