Re: [Elecraft] Rhombic antenna "gain"
Don - Thanks for your input. I should have gone into more detail. We did sustain a direct (yes, direct ...) lightning strike on our house in March, 2012. A freak storm after a week of 80F+ temps in Chicago. Lightning struck an attic roof fan, followed the wiring to the basement, and did nearly $100k damage to the house. I had NO antennas of any type up at that time. But I did subsequently have lightning protection professionally installed, consisting of a number of lightning rods on the roof all connected inside along the ridge line with 00 gauge stranded copper, running to 10 foot ground rods at both ends of the house. This wire runs well above the G5RV in the attic ... far enough to protect it and also far enough to 'not' act as a Faraday Cage. Would another direct strike still cause issues? Possibly, but I feel much more secure with that antenna in a storm than the outside EDZ. 73, Lyn, WØLEN -Original Message- From: Don Wilhelm [mailto:donw...@embarqmail.com] Sent: Saturday, September 14, 2019 8:51 AM To: l...@lnainc.com; 'Elecraft Reflector' Subject: Re: [Elecraft] Rhombic antenna "gain" Lyn, Hopefully you do not trust that an antenna in the attic will not be susceptible to lightning. I would not use ANY antenna during a thunderstorm. Shut down the station and ground all feedlines. 73, Don W3FPR On 9/14/2019 8:27 AM, Lyn Norstad wrote: > > Prior to the HOA changes, I was limited to a G5RV Jr. in the attic. It > worked fairly well, but nothing like this. I still use it as a backup > during thunderstorms when the EDZ is disconnected. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Hi Wes, You forgot to mention that Chris VK5MC was only running 150 watts output. His pattern dropped off drastically as the moon exited his window. When I built my humongous 144 MHz array in 1979/80, I figured that my window with VK5MC would be a bit wider with the added gain from the 24 yagi array. It hardly varied at all! He just got louder when I could hear him. I might have picked up one minute. Great fun thinking about those times! Thanks. To make this Elecraft related, I wish I had a K3 for my EME receiver instead of the Collins 75A4 that I was using back then. The APF would be fantastic on CW EME. It would have saved me a lot of time modifying the A4 to make it better!! I replaced the 6BA7 mixers with 6DJ8s. I took out an IF can and dropped in an R-390A 2.0 kHz mechanical filter. I had to add a 2N4416 FET to account for the added loss in the filter. The last big mod was to add another Collins 300 Hz crystal filter in the CW fillter position. I jury rigged it underneath the chassis on a bracket. I still have the 75A4 and did a cap replacement last winter. It had not been fired up since about 1992. It needed work. After it was all working fine again, I checked MDS (-138 dBm) and close in dynamic range at 2 kHz. I saw 92 dB which is not too shabby and in a different league than a stock A4. Still it is a good 10 dB below the K3. Dave K1WHS On 9/14/2019 12:09 PM, Wes wrote: I completed my 2-meter WAC by working VK5MC on December 3, 1982. Chris was using a rhombic, IIRC, 50 wavelengths on a leg and more-or-less fixed on his rising moon. I believe with some ropes he could "steer" one end to get a few minutes more on another couple of days a month of use. Otherwise it was a pretty short window. Modern Yagi designs blow these away. Wes N7WS __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to k1...@metrocast.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
[Elecraft] Rhombic Antenna Gain
I lived in Africa a long time ago in a game park so I had the opportunity to run a 700 foot long wire and later two long wires in a V beam. The gain was better than a yagi, the wires had lobes off them. I noticed that I didn't suffer from much fading. If you have space for a long wire or a v beam or a rhomic put it up. You can't rotate it but you will be heard very well in the direction of the wires. Theoretical doesn't come close to actual. There is no such thing as free space for us mortals. Our wires are all that we can know and I would do it all again if I was young and had the space. 73, Bill N2WL __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Hi Todd, Its not accurate to state that the Pusher FRD-13 CDAA is a " variant of the the FRD-10" CDAA. Their architectures are quite different and have little in common other than their circular shape. The FRD-13 relies on less effective (but much less expensive) analog RF phasing to develop its front-to-back ratio while the FRD-10 uses a massive (and extremely expensive) reflecting screen. Immediately after World War II, the Soviet Union built and deployed many dozens of Krug DF arrays, direct copies of the German Wullenweber DF array. Some of them are still in use and look almost exactly like the World War II Wullenweber arrays. www.thelivingmoon.com/45jack_files/04images/Krug/Odessa_I_PC030200_8965681.jpg 73 Frank W3LPL - Original Message - From: "Todd KH2TJ" To: elecraft@mailman.qth.net Sent: Saturday, September 14, 2019 7:25:39 AM Subject: Re: [Elecraft] Rhombic antenna "gain" Correct. USN had FRD-10's and USAF/US Army had FLR-9's. Lesser know variant of the FRD-10 was called the "Pusher". We had one out on Diego Garcia. About half the size of the FRD-10 iffen I reall correctly. I spent almost 5 1/2 years working at the one at NSGD Guam. 73, Todd KH2TJ >Hi mike, >Wasn't Rota an FRD-10, not an FLR-9? >73 >Frank >W3LPL __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to donov...@starpower.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
I was a lowly 2nd Lieutenant at Ft Monmouth in 1968. I was going thru a tropo scatter class. I used to love to drop in to K2USA in that wooden barracks building. I don't remember much except that it was waay cool to me. I wonder if there are any pictures of the place online? Dave K1WHS On 9/13/2019 11:17 PM, EricJ wrote: Maybe the termination was changed in later years. I was permanently assigned to K2USA from '63-'65 (not bad duty for a ham). We ran thousands of phone patches to/from SE Asia on that rhombic and the 20m monobander @ 90 feet. I used to break into QSOs between two local VKs chatting via ground wave with that antenna. I was the only signal they could hear. You probably knew Mike Reason. When I was there, he was a local kid who used to hang out at the MARS station. Great guy, now SK. Eric KE6US __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Lyn, Hopefully you do not trust that an antenna in the attic will not be susceptible to lightning. I would not use ANY antenna during a thunderstorm. Shut down the station and ground all feedlines. 73, Don W3FPR On 9/14/2019 8:27 AM, Lyn Norstad wrote: Prior to the HOA changes, I was limited to a G5RV Jr. in the attic. It worked fairly well, but nothing like this. I still use it as a backup during thunderstorms when the EDZ is disconnected. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
While I would love to have a rhombic, or multiple rhombics, it's not a consideration for me. But I do have a 2 acre "semi-rural" lot, and approx. 400 x 150 feet clear space behind the house. We have an HOA with antenna restrictions, but I managed to get elected to the board and was subsequently able to convince my colleagues to change the rules just a bit. After establishing my coverage goals and analyzing different options for best use of that space (including available supports) and my resources, I decided on an Extended Double Zepp. It's oriented to give me maximum gain at 3.5 MHz in a North-South direction with NVIS properties (desired), and maximum gain in an East-West direction on 40 meters. On 30 meters, and to a lesser degree on 20 meters, it produces NE, SE, SW and NW lobes. It tunes to a very useable match on all bands, 160 thru 6 meters. I feed it with 600 ohm True Ladder Line from a hybrid (4:1 voltage/1:1 current) balun in the attic requiring only about 20 feet of coax to the KPA/KAT500 in the shack. In a box outside I have a balanced line lightning arrestor, and also a heavy duty knife switch for positive antenna grounding (I am admittedly paranoid about lightning ...). It theoretically produces 4.7 dbi gain on the major lobes, and serves my purposes very well on all bands. Prior to the HOA changes, I was limited to a G5RV Jr. in the attic. It worked fairly well, but nothing like this. I still use it as a backup during thunderstorms when the EDZ is disconnected. Lyn, WØLEN -Original Message- From: elecraft-boun...@mailman.qth.net [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of Vic Rosenthal Sent: Saturday, September 14, 2019 5:56 AM To: Elecraft Reflector Subject: Re: [Elecraft] Rhombic antenna "gain" Just bring 600 ohm open line feedlines down from each end to a common point, where you have a relay or two to switch the feed and the terminating resistor. Then you can reverse it with a flip of the switch. Although transmit gain is the same as bidirectional, you can cut the noise by 3 dB. Victor 4X6GP > On 14 Sep 2019, at 2:21, Fred Jensen wrote: > > Mike: Rhombics can be operated either terminated or unterminated. If unterminated, they are bi-directional with half the power in each lobe. If terminated, the resistor absorbs half the power in the reverse lobe. Either way, half your power goes the "wrong" way, either behind your desired direction or heats a big resistor. They have a very low radiation angle and a fairly narrow beamwidth which is why they're flame throwers and very common in military and commercial stations, particularly in the days of point-to-point radio circuits. V-beams, sometimes called Half-Rhombics are sort of likewise only broader azimuth patterns more suitable for maritime ship-shore telegraphy circuits. For ham applications, Google W6AM > > 73, > Fred ["Skip"] K6DGW > Sparks NV DM09dn > Washoe County > >> On 9/13/2019 3:24 PM, Mike Markowski wrote: >> Can you expand on this, Ken, or if easier, a reference? I'm curious what tradeoffs are made. I used a rhombic at Ft. Monmouth, NJ before the Army base was closed in 2011, and used to boom into Europe and Russia. It was amazing. I also got copies of WWII manuals on rhombic construction while there. You know, just in case I became wealthy with tens of acres of land. :-) >> >> 73, >> Mike ab3ap > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to k2vco@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to l...@lnainc.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Yes, that came to mind here too. I figure that somebody will eventually plant beans and corn on the Bondville, IL site though. Chuck KE9UW c-haw...@illinois.edu Sent from my iPad > On Sep 13, 2019, at 10:42 PM, Arliss wrote: > > Or even longer: > > https://4.bp.blogspot.com/-UkbdbLQ-ofI/V4CWpqwJ9SI/E-Q/YtV82_PGUqg3j77n0OyOxp0A1LaL1-LowCLcB/s1600/crop-stonehenge-stones-set3.jpg > > > 73, Arliss W7XU > > >> On 9/13/2019 10:15 PM, donov...@starpower.net wrote: >> Hi Chuck, >> >> >> Its nearly impossible to hide those old Wullenweber arrays, even if they've >> been dismantled for nearly fifty years >> >> >> www.google.com/maps/search/bondville+rd,+scott,+il/@40.0492598,-88.3816964,440m/data=!3m1!1e3 >> >> >> 73 >> Frank >> W3LPL >> > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to c-haw...@illinois.edu __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
I completed my 2-meter WAC by working VK5MC on December 3, 1982. Chris was using a rhombic, IIRC, 50 wavelengths on a leg and more-or-less fixed on his rising moon. I believe with some ropes he could "steer" one end to get a few minutes more on another couple of days a month of use. Otherwise it was a pretty short window. Modern Yagi designs blow these away. Wes N7WS __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Just a question of phasing it properly. Of course it would be hard to do for multiple bands! Victor 4X6GP > On 14 Sep 2019, at 4:56, Fred Jensen wrote: > > Feed the termination power back into the antenna? Conservation of energy? > [:-) __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Just bring 600 ohm open line feedlines down from each end to a common point, where you have a relay or two to switch the feed and the terminating resistor. Then you can reverse it with a flip of the switch. Although transmit gain is the same as bidirectional, you can cut the noise by 3 dB. Victor 4X6GP > On 14 Sep 2019, at 2:21, Fred Jensen wrote: > > Mike: Rhombics can be operated either terminated or unterminated. If > unterminated, they are bi-directional with half the power in each lobe. If > terminated, the resistor absorbs half the power in the reverse lobe. Either > way, half your power goes the "wrong" way, either behind your desired > direction or heats a big resistor. They have a very low radiation angle and > a fairly narrow beamwidth which is why they're flame throwers and very common > in military and commercial stations, particularly in the days of > point-to-point radio circuits. V-beams, sometimes called Half-Rhombics are > sort of likewise only broader azimuth patterns more suitable for maritime > ship-shore telegraphy circuits. For ham applications, Google W6AM > > 73, > Fred ["Skip"] K6DGW > Sparks NV DM09dn > Washoe County > >> On 9/13/2019 3:24 PM, Mike Markowski wrote: >> Can you expand on this, Ken, or if easier, a reference? I'm curious what >> tradeoffs are made. I used a rhombic at Ft. Monmouth, NJ before the Army >> base was closed in 2011, and used to boom into Europe and Russia. It was >> amazing. I also got copies of WWII manuals on rhombic construction while >> there. You know, just in case I became wealthy with tens of acres of land. >> :-) >> >> 73, >> Mike ab3ap > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to k2vco@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Correct. USN had FRD-10's and USAF/US Army had FLR-9's. Lesser know variant of the FRD-10 was called the "Pusher". We had one out on Diego Garcia. About half the size of the FRD-10 iffen I reall correctly. I spent almost 5 1/2 years working at the one at NSGD Guam. 73, Todd KH2TJ >Hi mike, >Wasn't Rota an FRD-10, not an FLR-9? >73 >Frank >W3LPL __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
I guess they were used a many military sites. In 1984 I helped install a 250w commercial VHF link from top of Mt. Balleyhoo (above Dutch Harbor in the Aleutians) and there was the remains of many 90 foot wooden poles arrayed up in a valley on the side of the mountain that was used by the military in WWII. I would guess they held rhombic arrays as the poles were in lines with total length probably 1000-foot. Dutch Harbor was attacked by Japan in WWII but did not fall to the Japanese like Attu and Kiska Islands did. The campaigns often referred to as the "Forgotten War". Only US territory occupied by enemy forces since the war of 1812. There were abandoned concrete gun emplacements on the cliffs on top of the mountain - interesting to explore and look out of thinking how it was in 1942. 73, Ed - KL7UW http://www.kl7uw.com Dubus-NA Business mail: dubus...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Do a google on W6AM. Don was a ham's ham with many Rhombic antennas. Years ago he and W1FH for several years would exchange being on the top of the DXCC list. Interesting reading. 73 Bob W7AVK On 9/13/2019 8:22 PM, donov...@starpower.net wrote: Hi mike, Wasn't Rota an FRD-10, not an FLR-9? www.google.com/maps/place/36%C2%B039'24.0%22N+6%C2%B021'54.0%22W/@36.6567863,-6.3663994,682m/data=!3m1!1e3!4m2!3m1!1s0x0:0x0 73 Frank W3LPL - Original Message - From: "Michael P. Rioux" To: "Jim Campbell" Cc: elecraft@mailman.qth.net Sent: Saturday, September 14, 2019 1:26:20 AM Subject: Re: [Elecraft] Rhombic antenna "gain" I still get a kick out of thinking that I worked INSIDE of the antenna! (Rota’s FLR-9) Si vis pacem, para bellum Mike, W1USN On Sep 13, 2019, at 8:45 PM, Jim Campbell wrote: We also had Elephant Cages later on. Funny no one has mentioned them. If you want to see a real monster https://en.wikipedia.org/wiki/AN/FLR-9 <https://en.wikipedia.org/wiki/AN/FLR-9> Also known as a "Wullenweber" or AN/FLR-9. Jim - W4BQP On 9/13/2019 8:28 PM, Dick Dievendorff wrote: Small world. I was in a similar line of work, for the Navy, using an R-390, but I don't think we had Rhombics. This was in the mid-60's Lots of us in ham radio. 73 de Dick, K6KR -Original Message- From: elecraft-boun...@mailman.qth.net <mailto:elecraft-boun...@mailman.qth.net> mailto:elecraft-boun...@mailman.qth.net>> On Behalf Of Jim Campbell Sent: Friday, September 13, 2019 17:21 To: elecraft@mailman.qth.net <mailto:elecraft@mailman.qth.net> Subject: Re: [Elecraft] Rhombic antenna "gain" In the late '50s I was stationed at a field station in Northern Germany that was monitoring transmissions from the 'other side'. We were at a former WWII German airfield and had an antenna farm comprised of rhombics. I never bothered to count how many there were but I estimate that there were more than a dozen and they were in the order of 90' above ground. I was a ham at the time (DL4AQ) but not active. I believe that my K2 and a low 88' doublet hears better than would a rhombic and a SP-600 from those days. I almost can't believe the signals I'm hearing at the bottom of the sunspot cycle with said K2 and low 88' doublet. The old days weren't the good old days. 73, Jim - W4BQP . __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Not true. The KFS receive site building and some antennas are still there and being used for "something". In fact there is a web SDR hooked to the big log periodic. 73, Brian, K0DTJ HMB, CA > > KFS -- all gone now, not even buildings are left. __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
On 9/13/2019 8:15 PM, donov...@starpower.net wrote: > Its nearly impossible to hide those old Wullenweber arrays, even if they've > been dismantled for nearly fifty years The FCC's have all been dismantled. 73 de K2ASP - Phil Kane Elecraft K2/100 s/n 5402 >From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
On 9/13/2019 6:56 PM, Fred Jensen wrote: > I think the Half Moon Bay stn was KFS. It's brother site was in the mud > flats off of the Palo Alto shoreline in the Bay, all gone now. At least > one of the KFS transmitters is now operating at KPH. Ah yes, the PW-15, built for Press Wireless in the 1940s for continuous RTTY press transmissions at 15 KW. It's now running at 5 KW in CW mode and should last as long as we can get tubes for it. 73 de K2ASP - Phil Kane Elecraft K2/100 s/n 5402 From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
On 9/13/2019 6:56 PM, Fred Jensen wrote: > There was a small group of hams who either tried, or succeeded, in > getting permission to put one of the remaining Delano Sterba's on 160 > [and maybe 80]. I'm not sure if they were successful, As I remember it, it was the Sacramento Ham Club that got permission to use the antenna at VOA Dixon for a Field Day shortly after the VOA decommissioned the site. After they hooked everything up, they could not hear anything with it because of the high gain antenna picking up the signals from NPG - the Navy's transmitting site - two miles down the street. Someone forgot that there's a reason that receiving sites are located far, far away from such high-power transmitting sites. 73 de K2ASP - Phil Kane Elecraft K2/100 s/n 5402 From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
On 9/13/2019 5:47 PM, Jim Brown wrote: > There's another RX station along Rte 1 S of Half Moon Bay, with an > associated TX station around Palo Alto. KFS -- all gone now, not even buildings are left. 73 de K2ASP - Phil Kane Elecraft K2/100 s/n 5402 >From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
On 9/13/2019 5:45 PM, Jim Campbell wrote: > We also had Elephant Cages later on. Funny no one has mentioned them. They (we called them the "Type W") were the mainstay of the FCC's HFDF system from the 1970s to several years after I retired in the mid-1990s. Their function was directivity, not gain. We took the military's design and one of our engineers improved on it, and we usually outperformed theirs on tests. AFAIK all of the FCC's and the military's are now gone, replaced by more sophisticated DF antennas. 73 de K2ASP - Phil Kane Elecraft K2/100 s/n 5402 >From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
On 9/13/2019 4:18 PM, donov...@starpower.net wrote: > I visited many rhombic antenna farms many years ago (as far as I know > they've now all been dismantled). The Maritime Radio Historical Station KPH (ex-RCA) site in Bolinas, CA may still have one up, but I'm not certain that it is still in service - we've lost a number of antennas to weather damage and ageing poles and wires. I'm still waiting for our 8 MHz RTTY transmitting antenna to go back up. Unabashed commercial - www.radiomarine.com 73 de K2ASP - Phil Kane Elecraft K2/100 s/n 5402 >From a Clearing in the Silicon Forest Beaverton (Washington County) Oregon __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Or even longer: https://4.bp.blogspot.com/-UkbdbLQ-ofI/V4CWpqwJ9SI/E-Q/YtV82_PGUqg3j77n0OyOxp0A1LaL1-LowCLcB/s1600/crop-stonehenge-stones-set3.jpg 73, Arliss W7XU On 9/13/2019 10:15 PM, donov...@starpower.net wrote: Hi Chuck, Its nearly impossible to hide those old Wullenweber arrays, even if they've been dismantled for nearly fifty years www.google.com/maps/search/bondville+rd,+scott,+il/@40.0492598,-88.3816964,440m/data=!3m1!1e3 73 Frank W3LPL __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Hi mike, Wasn't Rota an FRD-10, not an FLR-9? www.google.com/maps/place/36%C2%B039'24.0%22N+6%C2%B021'54.0%22W/@36.6567863,-6.3663994,682m/data=!3m1!1e3!4m2!3m1!1s0x0:0x0 73 Frank W3LPL - Original Message - From: "Michael P. Rioux" To: "Jim Campbell" Cc: elecraft@mailman.qth.net Sent: Saturday, September 14, 2019 1:26:20 AM Subject: Re: [Elecraft] Rhombic antenna "gain" I still get a kick out of thinking that I worked INSIDE of the antenna! (Rota’s FLR-9) Si vis pacem, para bellum Mike, W1USN > On Sep 13, 2019, at 8:45 PM, Jim Campbell wrote: > > We also had Elephant Cages later on. Funny no one has mentioned them. If you > want to see a real monster https://en.wikipedia.org/wiki/AN/FLR-9 > <https://en.wikipedia.org/wiki/AN/FLR-9> Also known as a "Wullenweber" or > AN/FLR-9. > > Jim - W4BQP > On 9/13/2019 8:28 PM, Dick Dievendorff wrote: >> Small world. I was in a similar line of work, for the Navy, using an R-390, >> but I don't think we had Rhombics. This was in the mid-60's >> >> Lots of us in ham radio. >> >> 73 de Dick, K6KR >> >> -Original Message- >> From: elecraft-boun...@mailman.qth.net >> <mailto:elecraft-boun...@mailman.qth.net> > <mailto:elecraft-boun...@mailman.qth.net>> On >> Behalf Of Jim Campbell >> Sent: Friday, September 13, 2019 17:21 >> To: elecraft@mailman.qth.net <mailto:elecraft@mailman.qth.net> >> Subject: Re: [Elecraft] Rhombic antenna "gain" >> >> In the late '50s I was stationed at a field station in Northern Germany that >> was monitoring transmissions from the 'other side'. We were at a former WWII >> German airfield and had an antenna farm comprised of rhombics. I never >> bothered to count how many there were but I estimate that there were more >> than a dozen and they were in the order of 90' >> above ground. I was a ham at the time (DL4AQ) but not active. >> >> I believe that my K2 and a low 88' doublet hears better than would a rhombic >> and a SP-600 from those days. I almost can't believe the signals I'm hearing >> at the bottom of the sunspot cycle with said K2 and low 88' >> doublet. The old days weren't the good old days. >> >> 73, >> >> Jim - W4BQP >> >> >> >> __ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html Message >> delivered to d...@elecraft.com <mailto:d...@elecraft.com> >> >> > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > <http://mailman.qth.net/mailman/listinfo/elecraft> > Help: http://mailman.qth.net/mmfaq.htm <http://mailman.qth.net/mmfaq.htm> > Post: mailto:Elecraft@mailman.qth.net <mailto:Elecraft@mailman.qth.net> > > This list hosted by: http://www.qsl.net <http://www.qsl.net/> > Please help support this email list: http://www.qsl.net/donate.html > <http://www.qsl.net/donate.html> > Message delivered to m...@rioux.org <mailto:m...@rioux.org> __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to donov...@starpower.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Hi Chuck, Its nearly impossible to hide those old Wullenweber arrays, even if they've been dismantled for nearly fifty years www.google.com/maps/search/bondville+rd,+scott,+il/@40.0492598,-88.3816964,440m/data=!3m1!1e3 73 Frank W3LPL - Original Message - From: "charles j jr hawley" To: "Jim Campbell" Cc: elecraft@mailman.qth.net Sent: Saturday, September 14, 2019 1:42:53 AM Subject: Re: [Elecraft] Rhombic antenna "gain" I was in the radio direction finding group at the U of IL in the early 60's which had a Wullenweber site just west of Champaign-Urbana IL 120 antennas in a circle outside a screen supported by telephone poles. The locals had colorful ideas of what it was all about. You could listen to WWVH, Hawaii and WWV in MD separately on the same frequency by rotating receive about 180 degrees. Very impressive. Jack BMW Motorcycles Chuck KE9UW c-haw...@illinois.edu Sent from my iPad > On Sep 13, 2019, at 7:46 PM, Jim Campbell wrote: > > We also had Elephant Cages later on. Funny no one has mentioned them. If you > want to see a real monster https://en.wikipedia.org/wiki/AN/FLR-9 Also known > as a "Wullenweber" or AN/FLR-9. > > Jim - W4BQP >> On 9/13/2019 8:28 PM, Dick Dievendorff wrote: >> Small world. I was in a similar line of work, for the Navy, using an R-390, >> but I don't think we had Rhombics. This was in the mid-60's >> >> Lots of us in ham radio. >> >> 73 de Dick, K6KR >> >> -Original Message- >> From: elecraft-boun...@mailman.qth.net On >> Behalf Of Jim Campbell >> Sent: Friday, September 13, 2019 17:21 >> To: elecraft@mailman.qth.net >> Subject: Re: [Elecraft] Rhombic antenna "gain" >> >> In the late '50s I was stationed at a field station in Northern Germany that >> was monitoring transmissions from the 'other side'. We were at a former WWII >> German airfield and had an antenna farm comprised of rhombics. I never >> bothered to count how many there were but I estimate that there were more >> than a dozen and they were in the order of 90' >> above ground. I was a ham at the time (DL4AQ) but not active. >> >> I believe that my K2 and a low 88' doublet hears better than would a rhombic >> and a SP-600 from those days. I almost can't believe the signals I'm hearing >> at the bottom of the sunspot cycle with said K2 and low 88' >> doublet. The old days weren't the good old days. >> >> 73, >> >> Jim - W4BQP >> >> >> >> __ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html Message >> delivered to d...@elecraft.com > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to c-haw...@illinois.edu __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to donov...@starpower.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
A small correction. Delano, Dixon and further east Bethany were not VOA sites. They were originally private broadcaster’s sites. I can’t remember which was what but Bethany and Delano were CBS and NBC. Bethany was Crosley. Eventually VOA took these sites over as commercial broadcasters found little value in shortwave. Greenville was the only true VOA site on US soil. The engineers who kept these sites going were heros as many of those transmitters became antiques and in some cases had to fabricate parts. That is the unfortunate legacy of US shortwave broadcast. b Sent from my iPad >> On Sep 13, 2019, at 8:48 PM, Jim Brown wrote: >> >> On 9/13/2019 4:18 PM, donov...@starpower.net wrote: >> To compound the design compromises, the r hombic termination >> resistor throws away nearly 3 dB of whatever gain it might achieve. > > When our senior EE class toured Crosley's Mason, OH VOA site in 1964, the > engineers were quite proud of their modification to the design that fed the > termination power back into the feedpoint. All that remains of that > spectacular station is the transmitter building. When we toured it, there > were >25 rhombics and two Sterba Curtains. 10-15 years ago, my son worked as > the manager for a restaurant/bar on the land where the antenna farm used to > be. Several years ago, I drove by the VOA station at Delano, CA, about 45 > miles S of Visalia. At least some of the antenna farm was still there, but > inquiry told me that the transmitters were "somewhere in South America." At > the time, I had hopes of arranging a tour for Visalia DX Convention attendees. > > There are still some shore stations along the Pacific coast with rhombics. > The KPH TX and RX stations are 30-40 miles apart. There's another RX station > along Rte 1 S of Half Moon Bay, with an associated TX station around Palo > Alto. > > 73, Jim K9YC > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to w...@w2xj.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Symmetry? The whole show with rhombics is beamwidth and elevation angle, not really gain, which has been pointed out in much of the literature. A "perfect" rhombic will have an extremely narrow beamwidth in the 10 to 15 deg range at HF [and if large enough, at MF as well]. Asymmetry will distort that characteristic, and raise the amplitude of side lobes. Effective rhombics for ham usage will require an "array' of them with different headings. Lots of land, lots of property taxes. Stacked, rotatable yagi's might be a better choice if your bank account is sufficient. Trees growing inside a rhombic will slowly degrade its performance, yet another cost. Of course, you might be able to sell the lumber. [:-) 73, Fred ["Skip"] K6DGW Sparks NV DM09dn Washoe County On 9/13/2019 5:01 PM, David Haines wrote: Well, I'm not wealthy. But we do have 270 acres of forest-land covered with nothing but trees. So a rhombic or two sounds really good, which never occurred to me before. Thanks, Don! Across the field from my shack, maybe 600', is a row of 90' pine trees. More trees on either edge of the field for the vertices. And the feed could be right at the shack. How important is symmetry? I've been deciding how much Wireman #534 to buy, so it sounds like I should go for at least 1000'! Still will need a lot of support line, though. david, in the forests of Maine KC1DNY __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Many of the VOA transmitters were 250 KW and ended up in religious SW broadcast stations. There was a small group of hams who either tried, or succeeded, in getting permission to put one of the remaining Delano Sterba's on 160 [and maybe 80]. I'm not sure if they were successful, I do know that the antenna farm you can see from the highway is significantly smaller than I remember from the late 50's. I think the Half Moon Bay stn was KFS. It's brother site was in the mud flats off of the Palo Alto shoreline in the Bay, all gone now. At least one of the KFS transmitters is now operating at KPH. Feed the termination power back into the antenna? Conservation of energy? [:-) 73, Fred ["Skip"] K6DGW Sparks NV DM09dn Washoe County On 9/13/2019 5:47 PM, Jim Brown wrote: On 9/13/2019 4:18 PM, donov...@starpower.net wrote: To compound the design compromises, the r hombic termination resistor throws away nearly 3 dB of whatever gain it might achieve. When our senior EE class toured Crosley's Mason, OH VOA site in 1964, the engineers were quite proud of their modification to the design that fed the termination power back into the feedpoint. All that remains of that spectacular station is the transmitter building. When we toured it, there were >25 rhombics and two Sterba Curtains. 10-15 years ago, my son worked as the manager for a restaurant/bar on the land where the antenna farm used to be. Several years ago, I drove by the VOA station at Delano, CA, about 45 miles S of Visalia. At least some of the antenna farm was still there, but inquiry told me that the transmitters were "somewhere in South America." At the time, I had hopes of arranging a tour for Visalia DX Convention attendees. There are still some shore stations along the Pacific coast with rhombics. The KPH TX and RX stations are 30-40 miles apart. There's another RX station along Rte 1 S of Half Moon Bay, with an associated TX station around Palo Alto. 73, Jim K9YC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to k6...@foothill.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
I was in the radio direction finding group at the U of IL in the early 60's which had a Wullenweber site just west of Champaign-Urbana IL 120 antennas in a circle outside a screen supported by telephone poles. The locals had colorful ideas of what it was all about. You could listen to WWVH, Hawaii and WWV in MD separately on the same frequency by rotating receive about 180 degrees. Very impressive. Jack BMW Motorcycles Chuck KE9UW c-haw...@illinois.edu Sent from my iPad > On Sep 13, 2019, at 7:46 PM, Jim Campbell wrote: > > We also had Elephant Cages later on. Funny no one has mentioned them. If you > want to see a real monster https://en.wikipedia.org/wiki/AN/FLR-9 Also known > as a "Wullenweber" or AN/FLR-9. > > Jim - W4BQP >> On 9/13/2019 8:28 PM, Dick Dievendorff wrote: >> Small world. I was in a similar line of work, for the Navy, using an R-390, >> but I don't think we had Rhombics. This was in the mid-60's >> >> Lots of us in ham radio. >> >> 73 de Dick, K6KR >> >> -Original Message- >> From: elecraft-boun...@mailman.qth.net On >> Behalf Of Jim Campbell >> Sent: Friday, September 13, 2019 17:21 >> To: elecraft@mailman.qth.net >> Subject: Re: [Elecraft] Rhombic antenna "gain" >> >> In the late '50s I was stationed at a field station in Northern Germany that >> was monitoring transmissions from the 'other side'. We were at a former WWII >> German airfield and had an antenna farm comprised of rhombics. I never >> bothered to count how many there were but I estimate that there were more >> than a dozen and they were in the order of 90' >> above ground. I was a ham at the time (DL4AQ) but not active. >> >> I believe that my K2 and a low 88' doublet hears better than would a rhombic >> and a SP-600 from those days. I almost can't believe the signals I'm hearing >> at the bottom of the sunspot cycle with said K2 and low 88' >> doublet. The old days weren't the good old days. >> >> 73, >> >> Jim - W4BQP >> >> >> >> __ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html Message >> delivered to d...@elecraft.com > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to c-haw...@illinois.edu __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
I still get a kick out of thinking that I worked INSIDE of the antenna! (Rota’s FLR-9) Si vis pacem, para bellum Mike, W1USN > On Sep 13, 2019, at 8:45 PM, Jim Campbell wrote: > > We also had Elephant Cages later on. Funny no one has mentioned them. If you > want to see a real monster https://en.wikipedia.org/wiki/AN/FLR-9 > <https://en.wikipedia.org/wiki/AN/FLR-9> Also known as a "Wullenweber" or > AN/FLR-9. > > Jim - W4BQP > On 9/13/2019 8:28 PM, Dick Dievendorff wrote: >> Small world. I was in a similar line of work, for the Navy, using an R-390, >> but I don't think we had Rhombics. This was in the mid-60's >> >> Lots of us in ham radio. >> >> 73 de Dick, K6KR >> >> -Original Message- >> From: elecraft-boun...@mailman.qth.net >> <mailto:elecraft-boun...@mailman.qth.net> > <mailto:elecraft-boun...@mailman.qth.net>> On >> Behalf Of Jim Campbell >> Sent: Friday, September 13, 2019 17:21 >> To: elecraft@mailman.qth.net <mailto:elecraft@mailman.qth.net> >> Subject: Re: [Elecraft] Rhombic antenna "gain" >> >> In the late '50s I was stationed at a field station in Northern Germany that >> was monitoring transmissions from the 'other side'. We were at a former WWII >> German airfield and had an antenna farm comprised of rhombics. I never >> bothered to count how many there were but I estimate that there were more >> than a dozen and they were in the order of 90' >> above ground. I was a ham at the time (DL4AQ) but not active. >> >> I believe that my K2 and a low 88' doublet hears better than would a rhombic >> and a SP-600 from those days. I almost can't believe the signals I'm hearing >> at the bottom of the sunspot cycle with said K2 and low 88' >> doublet. The old days weren't the good old days. >> >> 73, >> >> Jim - W4BQP >> >> >> >> __ >> Elecraft mailing list >> Home: http://mailman.qth.net/mailman/listinfo/elecraft >> Help: http://mailman.qth.net/mmfaq.htm >> Post: mailto:Elecraft@mailman.qth.net >> >> This list hosted by: http://www.qsl.net >> Please help support this email list: http://www.qsl.net/donate.html Message >> delivered to d...@elecraft.com <mailto:d...@elecraft.com> >> >> > > __ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > <http://mailman.qth.net/mailman/listinfo/elecraft> > Help: http://mailman.qth.net/mmfaq.htm <http://mailman.qth.net/mmfaq.htm> > Post: mailto:Elecraft@mailman.qth.net <mailto:Elecraft@mailman.qth.net> > > This list hosted by: http://www.qsl.net <http://www.qsl.net/> > Please help support this email list: http://www.qsl.net/donate.html > <http://www.qsl.net/donate.html> > Message delivered to m...@rioux.org <mailto:m...@rioux.org> __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Also had an array of rhombics at Bingen, plenty of SP-600's. Used primarily for reception. Our GRC-26 used a dipole for xmt/rcv DF work. That was 55 to 58. I'd have loved to have my K3 and 3 el steppIR back then. They didn't get the FLR-9 at Chicksands until after I left in Jun 62. Got my ham license in Nov 61 while in G land but didn't operate until I got back stateside. Yeah, good ole days. 73, Rick W7LKG (ex 293x1) -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Jim Campbell Sent: Friday, September 13, 2019 17:46 To: elecraft@mailman.qth.net Subject: Re: [Elecraft] Rhombic antenna "gain" We also had Elephant Cages later on. Funny no one has mentioned them. If you want to see a real monster https://en.wikipedia.org/wiki/AN/FLR-9 Also known as a "Wullenweber" or AN/FLR-9. Jim - W4BQP On 9/13/2019 8:28 PM, Dick Dievendorff wrote: > Small world. I was in a similar line of work, for the Navy, using an > R-390, but I don't think we had Rhombics. This was in the mid-60's > > Lots of us in ham radio. > > 73 de Dick, K6KR > > -Original Message- > From: elecraft-boun...@mailman.qth.net > On Behalf Of Jim Campbell > Sent: Friday, September 13, 2019 17:21 > To: elecraft@mailman.qth.net > Subject: Re: [Elecraft] Rhombic antenna "gain" > > In the late '50s I was stationed at a field station in Northern > Germany that was monitoring transmissions from the 'other side'. We > were at a former WWII German airfield and had an antenna farm > comprised of rhombics. I never bothered to count how many there were > but I estimate that there were more than a dozen and they were in the order > of 90' > above ground. I was a ham at the time (DL4AQ) but not active. > > I believe that my K2 and a low 88' doublet hears better than would a > rhombic and a SP-600 from those days. I almost can't believe the > signals I'm hearing at the bottom of the sunspot cycle with said K2 and low > 88' > doublet. The old days weren't the good old days. > > 73, > > Jim - W4BQP > > > > __ > __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
On 9/13/2019 4:18 PM, donov...@starpower.net wrote: To compound the design compromises, the r hombic termination resistor throws away nearly 3 dB of whatever gain it might achieve. When our senior EE class toured Crosley's Mason, OH VOA site in 1964, the engineers were quite proud of their modification to the design that fed the termination power back into the feedpoint. All that remains of that spectacular station is the transmitter building. When we toured it, there were >25 rhombics and two Sterba Curtains. 10-15 years ago, my son worked as the manager for a restaurant/bar on the land where the antenna farm used to be. Several years ago, I drove by the VOA station at Delano, CA, about 45 miles S of Visalia. At least some of the antenna farm was still there, but inquiry told me that the transmitters were "somewhere in South America." At the time, I had hopes of arranging a tour for Visalia DX Convention attendees. There are still some shore stations along the Pacific coast with rhombics. The KPH TX and RX stations are 30-40 miles apart. There's another RX station along Rte 1 S of Half Moon Bay, with an associated TX station around Palo Alto. 73, Jim K9YC __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
We also had Elephant Cages later on. Funny no one has mentioned them. If you want to see a real monster https://en.wikipedia.org/wiki/AN/FLR-9 Also known as a "Wullenweber" or AN/FLR-9. Jim - W4BQP On 9/13/2019 8:28 PM, Dick Dievendorff wrote: Small world. I was in a similar line of work, for the Navy, using an R-390, but I don't think we had Rhombics. This was in the mid-60's Lots of us in ham radio. 73 de Dick, K6KR -Original Message- From: elecraft-boun...@mailman.qth.net On Behalf Of Jim Campbell Sent: Friday, September 13, 2019 17:21 To: elecraft@mailman.qth.net Subject: Re: [Elecraft] Rhombic antenna "gain" In the late '50s I was stationed at a field station in Northern Germany that was monitoring transmissions from the 'other side'. We were at a former WWII German airfield and had an antenna farm comprised of rhombics. I never bothered to count how many there were but I estimate that there were more than a dozen and they were in the order of 90' above ground. I was a ham at the time (DL4AQ) but not active. I believe that my K2 and a low 88' doublet hears better than would a rhombic and a SP-600 from those days. I almost can't believe the signals I'm hearing at the bottom of the sunspot cycle with said K2 and low 88' doublet. The old days weren't the good old days. 73, Jim - W4BQP __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to d...@elecraft.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Many years ago W1AW used to have a big (6 wavelengths per leg as I recall) rhombic for 20 meters pointed west. It was mainly used for the code practice and bulletin transmissions. When the new 90-foot tower with stacked monoband Yagis was installed we ran some A/B antenna tests on the air and asked people to send in signal reports. We found that the rhombic was equal or better than the stacked monobanders right on the boresight of the antenna but it had a narrower radiation pattern. The Yagis covered the west coast better overall. On the other hand, the rhombic was not as high (mounted on telephone poles) and it could be used on other bands, although with lower gain. By the way, the W1AW rhombic was unterminated as I recall. There really is no need to terminate a rhombic unless you are concerned about interference (on receive or transmit) in the rear direction. Alan N1AL On 9/13/19 4:21 PM, Fred Jensen wrote: Mike: Rhombics can be operated either terminated or unterminated. If unterminated, they are bi-directional with half the power in each lobe. If terminated, the resistor absorbs half the power in the reverse lobe. Either way, half your power goes the "wrong" way, either behind your desired direction or heats a big resistor. They have a very low radiation angle and a fairly narrow beamwidth which is why they're flame throwers and very common in military and commercial stations, particularly in the days of point-to-point radio circuits. V-beams, sometimes called Half-Rhombics are sort of likewise only broader azimuth patterns more suitable for maritime ship-shore telegraphy circuits. For ham applications, Google W6AM 73, Fred ["Skip"] K6DGW Sparks NV DM09dn Washoe County __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
In the late '50s I was stationed at a field station in Northern Germany that was monitoring transmissions from the 'other side'. We were at a former WWII German airfield and had an antenna farm comprised of rhombics. I never bothered to count how many there were but I estimate that there were more than a dozen and they were in the order of 90' above ground. I was a ham at the time (DL4AQ) but not active. I believe that my K2 and a low 88' doublet hears better than would a rhombic and a SP-600 from those days. I almost can't believe the signals I'm hearing at the bottom of the sunspot cycle with said K2 and low 88' doublet. The old days weren't the good old days. 73, Jim - W4BQP __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Mike: You will need more than "a few tens of acres" for rhombics, their beamwidth is so narrow that you will need an array of them. The transmit site for KOK ["Los Angeles Radio" now SK and demolished] was probably at least a square mile, likely more. Rhombics for the point-2-point services, horizontal V-beams for the maritime service. VOA was partial to Sterba and other "curtain" designs. Similar to rhombics in the gain and main lobe elevation departments, they exhibit wider beam widths which was good for broadcast to specific areas instead of specific cities. VOA had a large station in Dixon CA with multiple curtains which is gone now. The one in Delano CA was still there [inactive] last time we drove down CA99 to Bakersfield 5 or so years ago. They do require two or more very tall towers however. There's a trade-off equation. Rhombics are quite simple and do not require massive towers. They DO require a lot of land which must be factored into the total antenna cost. That land has to be kept clear of major vegetation too. Curtains take less land but are substantially more complex and more difficult to erect, inspect, and maintain. It always comes down to money. [:-)) Don Wallace, W6AM, was a legend on the west coast in the 40's/50's. His QTH was in the Palos Verde Hills [west of downtown Los Angeles] overlooking the Pacific with multiple rhombics. At that time, transmit power was measured by plate input power and our limit was 1 KW. W6AM had separate Collins KW-1 transmitters permanently tuned for each band, all the feedlines were open wire, and he basically talked to anyone he wanted to. I got a chance to visit the station as a teenager with a group ... had to ask my Elmer about the looong wires about 8 ft off the ground ... beverage RX antennas under and around all the rhombics. 73, Fred ["Skip"] K6DGW Sparks NV DM09dn Washoe County On 9/13/2019 3:24 PM, Mike Markowski wrote: Can you expand on this, Ken, or if easier, a reference? I'm curious what tradeoffs are made. I used a rhombic at Ft. Monmouth, NJ before the Army base was closed in 2011, and used to boom into Europe and Russia. It was amazing. I also got copies of WWII manuals on rhombic construction while there. You know, just in case I became wealthy with tens of acres of land. :-) 73, Mike ab3ap On 9/13/19 5:57 PM, Ken G Kopp wrote: Rhombic antennas derive their well-known gain by "throwing away" some of the design's gain. Ditto for the infamous "inverted vee". Use is made of the lobes from the four wires while disregarding others. 73 ! Ken Kopp - K0PP __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to k6...@foothill.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Well, I'm not wealthy. But we do have 270 acres of forest-land covered with nothing but trees. So a rhombic or two sounds really good, which never occurred to me before. Thanks, Don! Across the field from my shack, maybe 600', is a row of 90' pine trees. More trees on either edge of the field for the vertices. And the feed could be right at the shack. How important is symmetry? I've been deciding how much Wireman #534 to buy, so it sounds like I should go for at least 1000'! Still will need a lot of support line, though. david, in the forests of Maine KC1DNY On 9/13/2019 6:24 PM, Mike Markowski wrote: Can you expand on this, Ken, or if easier, a reference? I'm curious what tradeoffs are made. I used a rhombic at Ft. Monmouth, NJ before the Army base was closed in 2011, and used to boom into Europe and Russia. It was amazing. I also got copies of WWII manuals on rhombic construction while there. You know, just in case I became wealthy with tens of acres of land. :-) 73, Mike ab3ap On 9/13/19 5:57 PM, Ken G Kopp wrote: Rhombic antennas derive their well-known gain by "throwing away" some of the design's gain. Ditto for the infamous "inverted vee". Use is made of the lobes from the four wires while disregarding others. 73 ! Ken Kopp - K0PP __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to dhai...@bates.edu __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Mike: Rhombics can be operated either terminated or unterminated. If unterminated, they are bi-directional with half the power in each lobe. If terminated, the resistor absorbs half the power in the reverse lobe. Either way, half your power goes the "wrong" way, either behind your desired direction or heats a big resistor. They have a very low radiation angle and a fairly narrow beamwidth which is why they're flame throwers and very common in military and commercial stations, particularly in the days of point-to-point radio circuits. V-beams, sometimes called Half-Rhombics are sort of likewise only broader azimuth patterns more suitable for maritime ship-shore telegraphy circuits. For ham applications, Google W6AM 73, Fred ["Skip"] K6DGW Sparks NV DM09dn Washoe County On 9/13/2019 3:24 PM, Mike Markowski wrote: Can you expand on this, Ken, or if easier, a reference? I'm curious what tradeoffs are made. I used a rhombic at Ft. Monmouth, NJ before the Army base was closed in 2011, and used to boom into Europe and Russia. It was amazing. I also got copies of WWII manuals on rhombic construction while there. You know, just in case I became wealthy with tens of acres of land. :-) 73, Mike ab3ap __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Maybe the termination was changed in later years. I was permanently assigned to K2USA from '63-'65 (not bad duty for a ham). We ran thousands of phone patches to/from SE Asia on that rhombic and the 20m monobander @ 90 feet. I used to break into QSOs between two local VKs chatting via ground wave with that antenna. I was the only signal they could hear. You probably knew Mike Reason. When I was there, he was a local kid who used to hang out at the MARS station. Great guy, now SK. Eric KE6US ex-K1DCK, WA6YCF, WB2PVW On 9/13/2019 3:24 PM, Mike Markowski wrote: Can you expand on this, Ken, or if easier, a reference? I'm curious what tradeoffs are made. I used a rhombic at Ft. Monmouth, NJ before the Army base was closed in 2011, and used to boom into Europe and Russia. It was amazing. I also got copies of WWII manuals on rhombic construction while there. You know, just in case I became wealthy with tens of acres of land. :-) 73, Mike ab3ap On 9/13/19 5:57 PM, Ken G Kopp wrote: Rhombic antennas derive their well-known gain by "throwing away" some of the design's gain. Ditto for the infamous "inverted vee". Use is made of the lobes from the four wires while disregarding others. 73 ! Ken Kopp - K0PP __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to eric.c...@gmail.com __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Hi Mike, Rhombic antennas -- with few exceptions -- were not usually designed for high gain. They were usually designed as a compromise between gain and typically one octave of bandwidth (e.g. 14-28 MHz). To compound the design compromises, the r hombic termination resistor throws away nearly 3 dB of whatever gain it might achieve. Because of this, high gain transmitting rhombics have very narrow beamwidth, typically 20-30 degrees. A high gain rhombic designed for 14-28 MHz -- competitive with a pair of stacked large triband Yagis -- might be 300 feet wide, 700 feet long and supported by four 100 foot towers. In order to achieve this gain, the rhombic beamwidth would be only about 25 degrees, requiring at least a dozen huge reversable rhombics to cover most of the compass. I visited many rhombic antenna farms many years ago (as far as I know they've now all been dismantled). They were typically at least one square mile sites with fifty to a hundred towers with heights of 50 to more than 200 feet. Dismantled VOA Site C in Greenville, NC is a good example, a 1.5 square mile site with pairs of massive rhombics -- the biggest I've ever seen -- for diversity reception. To the extent these facilities are still operating (the vast majority are not), the rhombics were replaced by rotatable log periodic antennas, perhaps with higher power transmitters to make up for the slightly reduced gain. That approach replaces a one square miles ( in some cases much larger) with a few acres or perhaps 100 acres for very large site. This is a good reference: www.w8ji.com/rhombic_antennas.htm 73 Frank W3LPL - Original Message - From: "Mike Markowski" To: elecraft@mailman.qth.net Sent: Friday, September 13, 2019 10:24:32 PM Subject: Re: [Elecraft] Rhombic antenna "gain" Can you expand on this, Ken, or if easier, a reference? I'm curious what tradeoffs are made. I used a rhombic at Ft. Monmouth, NJ before the Army base was closed in 2011, and used to boom into Europe and Russia. It was amazing. I also got copies of WWII manuals on rhombic construction while there. You know, just in case I became wealthy with tens of acres of land. :-) 73, Mike ab3ap On 9/13/19 5:57 PM, Ken G Kopp wrote: > Rhombic antennas derive their well-known gain by "throwing away" some of > the design's gain. Ditto for the infamous "inverted vee". Use is made of > the lobes from the four wires while disregarding others. > > 73 ! > > Ken Kopp - K0PP __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to donov...@starpower.net __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
Re: [Elecraft] Rhombic antenna "gain"
Can you expand on this, Ken, or if easier, a reference? I'm curious what tradeoffs are made. I used a rhombic at Ft. Monmouth, NJ before the Army base was closed in 2011, and used to boom into Europe and Russia. It was amazing. I also got copies of WWII manuals on rhombic construction while there. You know, just in case I became wealthy with tens of acres of land. :-) 73, Mike ab3ap On 9/13/19 5:57 PM, Ken G Kopp wrote: Rhombic antennas derive their well-known gain by "throwing away" some of the design's gain. Ditto for the infamous "inverted vee". Use is made of the lobes from the four wires while disregarding others. 73 ! Ken Kopp - K0PP __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
[Elecraft] Rhombic antenna "gain"
Rhombic antennas derive their well-known gain by "throwing away" some of the design's gain. Ditto for the infamous "inverted vee". Use is made of the lobes from the four wires while disregarding others. 73 ! Ken Kopp - K0PP __ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
