Re: Topband: Radials on ground
Topbanders Here is my favorite article on ground radials by Al Christman K3LC. https://ncjweb.com/bonus-content/k3lcmaxgainradials.pdf Great reading but I continue to add more radials thus exceeding Al's suggested number. I also use Eight 3" aluminum irrigation pipes under each vertical that are 30' long in conjunction with 50 100' long wire radials. I use the irrigation pipe as radials rather than stack them behind the garage waiting for the price of aluminum to peak. 73, Carl W9LF -Original Message- From: Topband On Behalf Of Jim Brown Sent: Friday, January 7, 2022 12:36 PM To: topband@contesting.com Subject: Re: Topband: Radials on ground CAUTION: This email originated outside of the organization. This message might not be safe, use caution in opening it. If in doubt, do not open the attachment nor links in the message. On 1/7/2022 6:14 AM, Pete Smith N4ZR wrote: > is the size of wire used for on-the-ground radials - or elevated > radials for that matter - significant? The only significance is their mechanical characteristics to withstand physical conditions. > at least as compared to feeding the antenna against a single ground > rod. The earth is a big resistor. We do NOT want a connection to it, except for lightning protection. Indeed, radials have two functions -- to provide a low resistance path for the antenna's return current, and to SHIELD the antenna's field from the lossy earth. The only antennas whose performance benefit from an earth connection are receiving antennas. Conversations here can point us to consider other options, but are not a substitute for serious study of fundamentals. Real understanding of how stuff works is better obtained by study of the Handbook, the Antenna Book, and the ON4UN book. Rudy Severns, N6LF, has done a LOT of excellent work, in the form of interactive modeling concepts, building and measuring radial systems, modeling some more, and building measuring some more, then publishing what he's done and what he's learned. It's also well worth studying. https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.antennasbyn6lf.com%2Fdata=04%7C01%7CCarl.Braun%40cattron.com%7Cd80402cf63804d67fdd808d9d20c996c%7Ce3db7da86f894250a548d36f358a7d2a%7C0%7C0%7C637771774496971841%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000sdata=626vCzmEvqb1EpFh3eoEfr75LZDkDdenVM5y5VqU8IE%3Dreserved=0 Going to his site to find this link, I see that since my last visit, he's published some work on loop and loop on ground RX antennas. Almost ten years ago, I summarized what I'd learned from others on the topic of 160M antenna systems for limited space in a talk I've done at Visalia, Pacificon, and for several clubs including NCCC. Most of it is about radial and counterpoise systems. None of it is original work on my part. The slides are here. https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.antennasbyn6lf.com%2Fdata=04%7C01%7CCarl.Braun%40cattron.com%7Cd80402cf63804d67fdd808d9d20c996c%7Ce3db7da86f894250a548d36f358a7d2a%7C0%7C0%7C637771774496971841%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000sdata=626vCzmEvqb1EpFh3eoEfr75LZDkDdenVM5y5VqU8IE%3Dreserved=0 73, Jim K9YC _ Searchable Archives: https://nam12.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.contesting.com%2F_topbanddata=04%7C01%7CCarl.Braun%40cattron.com%7Cd80402cf63804d67fdd808d9d20c996c%7Ce3db7da86f894250a548d36f358a7d2a%7C0%7C0%7C637771774496971841%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000sdata=ty7%2BjOQ0rLBtbq8YRo5pEGa0OHwD%2FwRZ9VCMGIJV3uE%3Dreserved=0 - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Wednesday Night Activity
Hello Roger and Topbanders I heard G3YRO last night at 0024. You were good copy at S4 with heavy qsb. I threw every watt I had (120w) toward G3 but didn’t make it. You did send me a ? but no contact. Hang in there. I’ll have the amp cooking on 160 soon and we’ll get a contact in the log soon. 73 from Wisconsin where it is -18c now. Carl W9LF Get Outlook for iOS<https://aka.ms/o0ukef> From: Topband on behalf of Roger Kennedy Sent: Friday, December 31, 2021 12:59:46 PM To: topband@contesting.com Subject: Topband: Wednesday Night Activity CAUTION: This email originated outside of the organization. This message might not be safe, use caution in opening it. If in doubt, do not open the attachment nor links in the message. Well conditions had been pretty good all week up to Wednesday . . . I had plenty of QSOs right across the US, and was getting NA RBN S/N reports between +30 to 40dB, which is as good as it gets. However on Wednesday night I came on the band around Z, but saw that my RBN reports were way down - I figured this was likely to be due to QRN rather than propagation. So I didn't stay on very long. I tried again around 0300, but it was much the same. Incidentally, as I have mentioned previously, there always used to be a big peak on 160m signals around our Sunrise . . . but I find the reverse is true these days. Best reports from across North America are around 00.30 for me . . . signals drop off at least 10dB as you get near our Sunrise. (and I've noticed the same on receive, listening to lots of stations during the contests). So I rarely bother coming back on at Sunrise. Anyway, hopefully there will be lots of activity next Wednesday night. Happy New Year to everyone ! 73 Roger G3YRO _ Searchable Archives: https://nam12.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.contesting.com%2F_topbanddata=04%7C01%7CCarl.Braun%40cattron.com%7Cc0b3aed6f4074557e51108d9cc8fc5ee%7Ce3db7da86f894250a548d36f358a7d2a%7C0%7C0%7C637765740160400675%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000sdata=UdxI%2BVUI0ziPolkw5zAxnMuXMQTHB3%2FrxnkdkjBiQfk%3Dreserved=0 - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Great condx on 160M Dec 24, 21 - 0500Z-0600Z+
Hello Dan and Topbanders Great condx here in WI last night. Lots of activity from EU. ON4CT and OM2XW were particularly strong. S7 signals typical. I’m running two base loaded 70’ verticals in phase 1/8 spacing for general Omni TX/RX and 130w on this end. MX and HNY Carl W9LF Get Outlook for iOS<https://aka.ms/o0ukef> From: Topband on behalf of W7Rf Sent: Friday, December 24, 2021 12:30:05 AM To: Topband Subject: Topband: Great condx on 160M Dec 24, 21 - 0500Z-0600Z+ CAUTION: This email originated outside of the organization. This message might not be safe, use caution in opening it. If in doubt, do not open the attachment nor links in the message. Very nice condx now, worked over a dozen EU from Colorado, strong signals and low noise. Some over S9. Modest 160M station here, 165 foot inverted L and 1100 foot loop up 65 feet. 500 watts tonight. 73 to all Merry Christmas and Happy New Year Dan W7RF _ Searchable Archives: https://nam12.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.contesting.com%2F_topbanddata=04%7C01%7CCarl.Braun%40cattron.com%7C4dde579bdaa54c20981808d9c6a70e24%7Ce3db7da86f894250a548d36f358a7d2a%7C0%7C0%7C637759243562667784%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C2000sdata=f%2FBHrCZmSjSLKg31YhaJ4hpAW5IJ9XEnPWWOSXOmF9k%3Dreserved=0 - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: cheap radial wire?
Greg and list I started from scratch with my two element ground mounted vertical array. I’ve set quite a few radials and installing more before the snow hits here in the north woods. After doing lots of shopping for surplus wire I’ve settled on private sellers on eBay. I just purchased two 1000’ spools of 14ga stranded for $90 each. This was NOS wire and is made in USA. Free shipping on these heavy spools too. Good luck with your search! Carl W9LF Get Outlook for iOS<https://aka.ms/o0ukef> From: Topband on behalf of List Mail Sent: Monday, November 8, 2021 5:49:32 PM To: Greg Davis ; topband@contesting.com Subject: Re: Topband: cheap radial wire? CAUTION: This email originated outside of the organization. This message might not be safe, use caution in opening it. If in doubt, do not open the attachment nor links in the message. I can only relate my experience in Australia, where wire is expensive. After investigating bulk wire from manufacturers here, electrical wholesalers, etc., I ended up buying spools of “Building Wire”. I purchased 20 x 100 m rolls of 1.5 mm building wire from an electrical wholesaler at AUD29/roll. The 7-strand wire is fairly small, but with the PVC insulation, quite good to handle, doesn’t spring or coil and I buried it with a fitting I constructed for the tractor. Good luck, Luke VK3HJ. Sent from Mail for Windows From: Greg Davis Sent: Tuesday, 9 November 2021 9:20 AM To: topband@contesting.com Subject: Topband: cheap radial wire? Hello Topbanders, I recently reached out directly to a few people who had posted recently(ish) to this email reflector who had described purchasing large amounts of wire for radials at a (relative) bargain price. However, after a couple of weeks of waiting, none of those emails have been responded to. I've got a new-and-improved plan for my 160m vertical in my back yard, but, at this moment in time, the biggest thing holding me back is the wire for a sufficient radial field. Do any of you have spools of wire you're willing to sell to me if the price is right? Or suggestions for me where I can purchase it for a reasonable price? Thank you. 73 de Greg N3ZL _ Searchable Archives: https://nam12.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.contesting.com%2F_topbanddata=04%7C01%7CCarl.Braun%40cattron.com%7C53ee1adaaa764abe6a2208d9a3127f76%7Ce3db7da86f894250a548d36f358a7d2a%7C0%7C0%7C637720122126194747%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000sdata=Cmuu8Tp07lD%2B5Y%2Fx86lcJg7trJf8m5dv4YwX%2BRmj%2FIc%3Dreserved=0 - Topband Reflector _ Searchable Archives: https://nam12.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.contesting.com%2F_topbanddata=04%7C01%7CCarl.Braun%40cattron.com%7C53ee1adaaa764abe6a2208d9a3127f76%7Ce3db7da86f894250a548d36f358a7d2a%7C0%7C0%7C637720122126194747%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000sdata=Cmuu8Tp07lD%2B5Y%2Fx86lcJg7trJf8m5dv4YwX%2BRmj%2FIc%3Dreserved=0 - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: S9OK 160m EU
S9OK was light with me last night here in northern WI but I could copy. Listened to the pile up...up...upwith lots of east coasters calling from NA but hearing VERY few stations west of me. I was listening on an 80m vertical so less than ideal RX antenna. 73, Carl W9LF -Original Message- From: Topband On Behalf Of Bill Weaver Sent: Wednesday, October 6, 2021 8:33 AM Cc: topband reflector Subject: Re: Topband: S9OK 160m EU CAUTION: This email originated outside of the organization. This message might not be safe, use caution in opening it. If in doubt, do not open the attachment nor links in the message. Andy, You were a fairly solid 529 into Central KY on my GAP vertical (Poor RX antenna). I gave you a few calls with no luck (apparently a bad TX antenna also :)). S9OK was just under the noise level. Work begins this weekend on a HI-Z 4-square :). 73, Bill WE5P Comfortably Numb > On Oct 6, 2021, at 00:03, Andree DL8LAS via Topband > wrote: > > Hey topbanders, nice signal from S9OK this morning in DL. Worked also first > west coast this season. N7UA was real 559 today. Here is a short clip from > S9OK. > https://nam12.safelinks.protection.outlook.com/?url=https%3A%2F%2Fyoutu.be%2Fv-O-PGtM9oAdata=04%7C01%7CCarl.Braun%40cattron.com%7C51cb4ebad3d34e18bafa08d988ce0973%7Ce3db7da86f894250a548d36f358a7d2a%7C0%7C0%7C637691242305371802%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000sdata=%2BDwinG0fiZ9cjcdxJLQZg%2Fjz9nzNZ2Ua7sSNdozhVtQ%3Dreserved=0 > 73 Andy DL8LAS > https://nam12.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.dl8las.com%2Fdata=04%7C01%7CCarl.Braun%40cattron.com%7C51cb4ebad3d34e18bafa08d988ce0973%7Ce3db7da86f894250a548d36f358a7d2a%7C0%7C0%7C637691242305371802%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000sdata=iLU4eZmGl4iC8QbGyTBMi9eWeWizEAk%2FLc8H81MZ4CE%3Dreserved=0 > _ > Searchable Archives: > https://nam12.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.contesting.com%2F_topbanddata=04%7C01%7CCarl.Braun%40cattron.com%7C51cb4ebad3d34e18bafa08d988ce0973%7Ce3db7da86f894250a548d36f358a7d2a%7C0%7C0%7C637691242305371802%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000sdata=kYISuuelbeeG1lkKTpuXlJ6t8F1L8UZNNrJ27J7Yur8%3Dreserved=0 > - Topband Reflector _ Searchable Archives: https://nam12.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.contesting.com%2F_topbanddata=04%7C01%7CCarl.Braun%40cattron.com%7C51cb4ebad3d34e18bafa08d988ce0973%7Ce3db7da86f894250a548d36f358a7d2a%7C0%7C0%7C637691242305381753%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000sdata=C6Y5xlK%2BMOdnH4EUm1MnadxxOut%2F06ZS4PPrqh%2BLWp4%3Dreserved=0 - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Topband: Ground Radial question - Perimeter connections
Hello Topbanders Another question for the experts... When installing ground radials on a ground mounted vertical, how critical is it to connect those radials together at the far ends? Some technical references show the outer tips of the ground radials connected with what they call 'perimeter connections' and I'm wondering if these connections really add value to the ground radial screen. Has anyone modeled a single vertical or an array with and without these 'perimeter connections' to determine if they are worth the time and effort to install? Please advise. Thank you Carl W9LF _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: New Subject: 160M array feedline question
Topbanders Thanks to all who responded I received a lot of good advice and will be taking it. Specifically, the advice to bury the hardline rather than elevate it. Some brought up the idea of my ground mounted radials becoming submerged in fresh water...however, that would only take place for a week or less during the spring here and, it would only happen if we had a slow snow pack melt and rain at the same time. This happened here two years ago but only lasted for a week or so. I am sure to have more questions as this project matures. In the meantime, I will continue to work with my modified 80/160 Butternut vertical that's stuck in the snow. It uses 4 pieces of 30' irrigation tubing for radials as well as some wayward wires to create the ground screen. No amplifier. This winter I have 22 countries on 160 with it. Looking forward to the array! Thanks again Carl W9LF From: Carl Braun Sent: Sunday, March 21, 2021 3:26 PM To: topband@contesting.com Subject: New Subject: 160M array feedline question Hello Topbanders I am currently awaiting the snow to melt here in the Northwoods of Wisconsin before starting the construction of my low band vertical array. My verticals will be mounted in a low ground area near a lake and the area tends to get wet and sometimes floods in the early spring. Water levels could reach 6" to 12" above ground. My concerns relate to the hardline coaxial cable that will run from my lighting arrestor panel at the outside of my shack to the center of the two element vertical array which is 250' away. I will be using 1 5/8" hardline that I was able to snag for a very good deal but am concerned about having the cable lying on the ground and possible become submerged should we get significant rain with the snow melt. My plan is to elevate the feedline approximately 24" above the ground using old sections of Rohn 25 tower spaced every 10' or so. Each vertically mounted 5' chunk of Rohn 25 will be buried 2' into the ground have a 3' 2x6 board laying horizontally across the tower that would act as a coaxial "shelf" that will keep the hardline out of the water and prevent any significant drooping between these Rohn support sections. My question for the forum is related to the fact that I will have an elevated coaxial feedline with two ground mounted vertical antennas. I plan to use an UNUN or similar line isolator/choke that would keep the hardline from becoming a extra radial. Any thoughts from the forum on this set up? Any extra precautions I should take to keep return currents from flowing on the feedline? Thanks in advance for any suggestions. Carl W9LF _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Topband: New Subject: 160M array feedline question
Hello Topbanders I am currently awaiting the snow to melt here in the Northwoods of Wisconsin before starting the construction of my low band vertical array. My verticals will be mounted in a low ground area near a lake and the area tends to get wet and sometimes floods in the early spring. Water levels could reach 6" to 12" above ground. My concerns relate to the hardline coaxial cable that will run from my lighting arrestor panel at the outside of my shack to the center of the two element vertical array which is 250' away. I will be using 1 5/8" hardline that I was able to snag for a very good deal but am concerned about having the cable lying on the ground and possible become submerged should we get significant rain with the snow melt. My plan is to elevate the feedline approximately 24" above the ground using old sections of Rohn 25 tower spaced every 10' or so. Each vertically mounted 5' chunk of Rohn 25 will be buried 2' into the ground have a 3' 2x6 board laying horizontally across the tower that would act as a coaxial "shelf" that will keep the hardline out of the water and prevent any significant drooping between these Rohn support sections. My question for the forum is related to the fact that I will have an elevated coaxial feedline with two ground mounted vertical antennas. I plan to use an UNUN or similar line isolator/choke that would keep the hardline from becoming a extra radial. Any thoughts from the forum on this set up? Any extra precautions I should take to keep return currents from flowing on the feedline? Thanks in advance for any suggestions. Carl W9LF _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: I need help proofing an Inverted L model I made please. 40’ x 143’, four 100’ radials, #14 wire.
Jim, It looks like you connect wires to lossy ground. Do you have the NEC-4 engine with your EZNEC ver 6.0? Carl K9LA _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Cycle 25 predictions
Thanks for the updated info, Steve. Yes, a big Cycle 25 would still be in the picture. My little QRP 10m transceiver will see some use! Ooops, sorry - this is the topband reflector. Carl K9LA _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Cycle 25 predictions
Guy, I agree that looking at the magnetic cycle inside the Sun is the way to go. The McIntosh, et al, prediction for a big cycle is based on their assumption that the termination date for the Cycle 24 magnetic cycle was April 2020. But in Dr. Scott McIntosh’s presentation of November 11, 2020, he stated that the termination date for Cycle 24 has not yet occurred. As the Cycle 24 termination date moves out, the prediction for the Cycle 25 amplitude will become smaller per their data in their paper. So the important question is "when will the Cycle 24 termination date occur?" Carl K9LA _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Topband: WWDXC Top Band Anthologies
Rich N8UX, I have Volume 1 (1998) and Volume 2 (2000). Both are edited by N0AX, so ping him for more info. Carl K9LA _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: OT - Bonding Radials at Intersections
Frank, “Must” is a strong word. What goes wrong if you cross them? 73, Carl WS7L On Thu, Nov 5, 2020 at 9:47 PM wrote: > Hi Bob, > > > While bonding the radials is desirable, its not essential. But you > must NOT cross the radials over each other. > > > ... > 73 > Frank > W3LPL > > > > > > - Original Message - > > From: "Robert L. Chortek" > To: "TopBand List" > Sent: Friday, November 6, 2020 2:05:43 AM > Subject: Topband: OT - Bonding Radials at Intersections > > I just finished installing a two element vertical array on 40M. The > instructions say to bond the radials from one vertical where they intersect > with a radial for the other vertical. > > My question is, is this really necessary and what effect would doing so > (or not) have on the performance of the Array? > > Much appreciated. > > 73, > > Bob AA6VB > > Bob > Robert L. Chortek > _ > Searchable Archives: http://www.contesting.com/_topband - Topband > Reflector > > _ > Searchable Archives: http://www.contesting.com/_topband - Topband > Reflector > _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Ap progression graph from swpc.noaa.gov
Nick VE7DXR, At least they corrected the vertical axis of the 10.7 cm solar flux plot - it used to say sunspot number. What I do for the Ap is download the data from "Table of Recent Solar Indices (Preliminary) of Observed Monthly Mean Values" in the Data tab below the plots and import the data into Excel. Carl K9LA On Sat, Apr 18, 2020 at 2:30 PM Nick Hall-Patch wrote: > Does anyone know if the "ISES solar cycle Ap progression" graph > (example at http://n5pa.com/swpc-solarcycleapprogression.php) is no > longer being provided? (or being provided elsewhere?) > > NOAA has recently updated their solar cycle progression page > (https://www.swpc.noaa.gov/products/solar-cycle-progression), and it > now includes only sunspots and solar flux progression over the years. > > > Thanks. > > Nick > VE7DXR > > Nick Hall-Patch > Victoria, BC > Canada > > _ > Searchable Archives: http://www.contesting.com/_topband - Topband > Reflector > _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: CQ...CQ...CQ
Yes, lets do it, Carl, N6TVN. On 3/17/20 4:15 PM, VE6WZ_Steve wrote: With many hams around the world staying home and "practicing social distancing” to “flatten the CV-19 curve”, what a great time to be on the radio! Lets get out there and call CQ to stir up the band. (or ANY band for that matter) There may be some out there that somehow think calling CQ is just for the rare DX, and not for the average ham. I know there are many that have no interest in woking just “plain old DX” that aren't new DXCC counters. I also realize there are many that live in high noise city locations that have a legitimate “alligator risk” by calling CQ. However, to state the obvious, if no one calls CQ, no one is going to work anyone! The conclusion will be “the band is dead”. Speaking of another benefit of RBN…..one comment…..”if I look at my waterfall and don't see any traces, then the band is dead”. Well….often NOT true. It is not unusual to see a blank pan-adapter, but then when checking the RBN there is NO-ONE calling CQ….anywhere in the world! Is the band really dead?? How do we know it's dead if no one is calling? (And yes, there are enough RBN skimmers worldwide that almost any CQ will be decoded within a few seconds) Many nights I have CQ'd into a “dead band” (blank pan-adapter, but also no RBN activity) and been rewarded with lots of EU DX callers. There are a number of NA stalwarts calling CQ regularly on TB and a handful from EU, VK and JA, but it would be great to see more activity. (last night I heard Jon AA1K filling his log with EU). This winter I have worked quite a few EU that have been running 100w from backyard antennas so it's not limited to the big guns. For those that lament that everyone is on FT-8, perhaps it would be a good idea to get on the band and make some CW noise instead of waiting for some else to call CQ??? Thats what the FT-8 guys are doing…they hit the send key on the FT-8 program and wait to see what happens. There is a lot of FT-8 CQing going on…every 15 seconds, for hours. Maybe thats why it seems there is more DX being worked on that mode? This season I have logged 1,587 EU QSOs on CW with 498 unique callsigns, so CQing can be rewarding. 113 DXCC since August. This has been one of the best TB seasons here at VE6WZ. The season is not over yet. While stuck at home, turn on the radio and call CQ….on ANY band. See what happens. Kinda like “old school” radio…using the “legacy" mode. CQ..CQ…CQ….. Why not? 73, de steve ve6wz _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: NVIS Antenna
For those who are antenna challenged, don't sell a 160m inverted-vee at low height too short. My 160m antenna at the moment is an inverted-vee at an apex of 45 feet. Additionally, the last third of each end is at 90 degrees to the main portion and horizontal at only 7 feet or so off the ground. It's what fits on the property. In the CQ 160m CW contest in January 2017. I came away with 44 states (missed ME, ID, NE and AK), 7 Canadian provinces (VE9, VY2, VE2, VE3, VE5, VE6 and VE7) and 17 DXCC entities (mostly Caribbean, Central America, Mexico and South America, with a few Europeans, a North African and a KH6 in the mix). I was seldom #1 in a pile-up, but eventually I usually got through with 800 Watts to the inv-vee. It's better than no antenna. Carl K9LA _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Topband: Fwd: [QRP-L] HU1DL German DXpedition in El Salvador by N6TVN
Forwarded Message Subject:[QRP-L] HU1DL German DXpedition in El Salvador Date: Wed, 12 Feb 2020 06:50:33 -0500 From: Bobby Drummond Reply-To: QRP-L Mailing List To: QRP-L Mailing List According to their QRZ page, this group's DXpedition is about to end (they show on their page that they will be active until Feb 13th) Couldn't sleep well last night, so I got up very early and managed to catch them before sun was up locally on the 160 meter band using the homebrew tube transmitter and the Heathkit VF-1 VFO. I had heard them on some other bands recently but wasn't ever able to work them due to the competition in the pile ups they created. It was great to work them this morning, luckily, before they shut down their DX operations. I rarely get a chance to work El Salvador* and to work this one on 160 meters with the homebrew transmitter rig was an extra thrill. This also let's me add another country to my 160 meter countries list. * third contact with El Salvador - once on 30 meters, once on 12 meters and now once on 160 meters in a 9 year span) -- 73 de AK4JA __ QRP-L mailing list Home: http://mailman.qth.net/mailman/listinfo/qrp-l Help: http://mailman.qth.net/mmfaq.htm Post: mailto:qr...@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...@sonic.net _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Topband: Fwd: Re: [QRP-L] HU1DL German DXpedition in El Salvador by N6TVN
Forwarded Message Subject:Re: [QRP-L] HU1DL German DXpedition in El Salvador Date: Wed, 12 Feb 2020 09:22:50 -0500 From: Bobby Drummond Reply-To: QRP-L Mailing List To: QRP-L Mailing List A very poor one for DX, for sure. It's my 160 meter doublet with one end of it fallen down near the ground. The other is up about 65 feet above ground level and the center is also about 65 feet above ground level. It is fed with 450 ohn window line and an almost 40 year old MFJ tuner with a larger than factory sized balun. In spite of my less-than-ideal antenna, a very good operator at the El Salvador end of the QSO pulled me out (after multiple tries) and it's in the log now. On Wed, Feb 12, 2020 at 8:16 AM Mike Maiorana wrote: Nice going Bobby! What kind of antenna do you use on 160? 73 Mike M. KU4QO On Wed, Feb 12, 2020 at 6:51 AM Bobby Drummond wrote: According to their QRZ page, this group's DXpedition is about to end (they show on their page that they will be active until Feb 13th) Couldn't sleep well last night, so I got up very early and managed to catch them before sun was up locally on the 160 meter band using the homebrew tube transmitter and the Heathkit VF-1 VFO. I had heard them on some other bands recently but wasn't ever able to work them due to the competition in the pile ups they created. It was great to work them this morning, luckily, before they shut down their DX operations. I rarely get a chance to work El Salvador* and to work this one on 160 meters with the homebrew transmitter rig was an extra thrill. This also let's me add another country to my 160 meter countries list. * third contact with El Salvador - once on 30 meters, once on 12 meters and now once on 160 meters in a 9 year span) -- 73 de AK4JA __ QRP-L mailing list Home: http://mailman.qth.net/mailman/listinfo/qrp-l Help: http://mailman.qth.net/mmfaq.htm Post: mailto:qr...@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 zfr...@gmail.com __ QRP-L mailing list Home: http://mailman.qth.net/mailman/listinfo/qrp-l Help: http://mailman.qth.net/mmfaq.htm Post: mailto:qr...@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 alphak...@gmail.com -- 73 de AK4JA __ QRP-L mailing list Home: http://mailman.qth.net/mailman/listinfo/qrp-l Help: http://mailman.qth.net/mmfaq.htm Post: mailto:qr...@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...@sonic.net _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Topband: Fwd: [QRP-L] HU1DL German DXpedition in El Salvador by N6TVN
Forwarded Message Subject:[QRP-L] HU1DL German DXpedition in El Salvador Date: Wed, 12 Feb 2020 06:50:33 -0500 From: Bobby Drummond Reply-To: QRP-L Mailing List To: QRP-L Mailing List According to their QRZ page, this group's DXpedition is about to end (they show on their page that they will be active until Feb 13th) Couldn't sleep well last night, so I got up very early and managed to catch them before sun was up locally on the 160 meter band using the homebrew tube transmitter and the Heathkit VF-1 VFO. I had heard them on some other bands recently but wasn't ever able to work them due to the competition in the pile ups they created. It was great to work them this morning, luckily, before they shut down their DX operations. I rarely get a chance to work El Salvador* and to work this one on 160 meters with the homebrew transmitter rig was an extra thrill. This also let's me add another country to my 160 meter countries list. * third contact with El Salvador - once on 30 meters, once on 12 meters and now once on 160 meters in a 9 year span) -- 73 de AK4JA __ QRP-L mailing list Home: http://mailman.qth.net/mailman/listinfo/qrp-l Help: http://mailman.qth.net/mmfaq.htm Post: mailto:qr...@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...@sonic.net _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Inquiring minds want to know....
> What the heck happened that I could hear a > long wave signal over 2000 miles away at mid day? For a given electron density profile, the amount of refraction incurred by an electromagnetic wave is inversely proportional to the square of the frequency. The result of that is the lower the frequency, the less high the wave gets into the ionosphere. LF hardly reaches the absorbing region (the D region during the day), and thus LF suffers minimal ionospheric absorption. The wave refracts between the lower ionosphere and Earth - also known as the Earth-ionosphere wave guide. NO3M has heard VK4YB on 2200m (137 KHz) many times. I'm sure there are other examples like that out there. Carl K9LA _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: COSMIC RAY UPDATE
Hi to everyone, >From ionization rates in the scientific literature, galactic cosmic rays (GCRs) result in more electrons down low in the ionosphere (from collisional ionization) - where ionospheric absorption occurs. So one would think that the more cosmic rays, the more absorption - which is not good for 160m (with absorption inversely proportional to the square of the frequency, 80m is affected much less). Is there a direct one-to-one relationship between GCRs and 160m propagation? I don't know because there are other processes going on in the lower ionosphere that may also impact 160m. Trying to tie one single parameter to 160m propagation is not likely the entire story. As for the geomagnetic field (Ap) not being as low yet as in the last solar minimum, the lowest Ap occurs right at solar minimum or just after - when coronal holes (generally not CMEs) during the declining phase of the solar cycle decrease. So 160m continues to be a mystery - and I'm glad of it. Carl K9LA _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: a "WZ" kind of night
It was daylight here (a few mins. past sr) 73 Carl SM6CPY Den tis 12 nov. 2019 kl 18:10 skrev Larry via Topband < topband@contesting.com>: > got home late, around 0630z and caught a huge EU opening at their sunrise. > logged 16 EU in 20 minutes. yes! > finally the skip comes to the southern west coast. happy me. > larryn7dd > _ > Searchable Archives: http://www.contesting.com/_topband - Topband > Reflector > _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Topband: unwelcome topics
Does this mean a topic like "What Makes 160m Tick" would not be welcome? Couldn't resist. Carl K9LA _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Topband: big antenna site - ID'ed
For the record, that site belongs to NO8D. Carl K9LA _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Topband: big antenna site
I was in the Cleveland area several weeks ago, and saw some big towers with lots of what looks like Yagis. This site is at 41.2312991 latitude and -81.58989168 longitude for those who want to look at it with Google Earth. It is about 2 miles east of the junction of I-77 and I-271, and about 17.5 miles southeast of Cleveland Hopkins airport. One of the arrays appears to be five towers with no antennas - four of the towers are in a square and the fifth tower is in the center. Could this be a low band electronically-steerable array? Does anyone know if this is a ham installation? Or a commercial installation? Or something else? Carl K9LA _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Vertical antennas aren't always best for DX everywhere - the facts
What Steve and Nick VE7DXR were referring to is the geomagnetic latitude in relation to polarization - not ground conductivity. This involves the ordinary and extraordinary waves that propagate through the ionosphere, and how 160m is affected by being close to the electron gyro-frequency. Carl K9LA _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: 160m Condx
In Scandinavia freq´s above 1824 are the best. No fishnet beacons there. Carl Den ons 14 nov. 2018 kl 10:54 skrev Paul Mclaren : > I hadn't seen it mentioned but here in NW EU the continuous dashes from > Fish Net beacons can be a pain at times. > > Regards > > Paul MM0ZBH > > On Wed, 14 Nov 2018 at 08:55, Petr Ourednik wrote: > > > Hi, > > > > an old article here: > > > > > > > https://160mband.blogspot.com/2018/02/the-forbidden-dx-frequencies-table-on.html > > > > 73 - Petr, OK1RP > > > > On Wed, Nov 14, 2018, at 1:54 AM, Saulius Zalnerauskas wrote: > > > Thanks, > > > How about JA? > > > 1810-1824.9 > > > Where is better not CQ? > > > Sam LY5W > > > Just back home from W6 > > > > > > 2018-11-12, pr 20:27 Mike Waters > > > > > > Perfect! Thanks for sharing. > > > > > > > > 73, Mike > > > > www.w0btu.com > > > > > > > > On Mon, Nov 12, 2018 at 12:13 PM VE6WZ_Steve wrote: > > > > > > > > > Know bad frequencies- great resource here: > > > > > http://www.k8nd.com/TopbandBadFreqs.pdf > > > > > > > > > > However…a “best practice” on 160m is NEVER call CQ on an exact > > frequency. > > > > > Why is it ever necessary to call on 1830, 1820, 1822 etc. exactly? > > Call > > > > CQ > > > > > on 1820.3, or 1820.4 or 1822.6 or 1827.8. > > > > > Perhaps its human nature to want to use a nice “round” number, but > > this > > > > > accomplishs nothing except increase the chances of being on a > > harmonic > > > > QRG. > > > > > Its surprising how many DX-peds will do this too. We don't need a > > nice > > > > > frequency with no decimal points! You will be found just fine with > > all > > > > the > > > > > skimmers and spotters out there. > > > > > > > > > > de steve ve6wz. > > > > > > > > > > > > > > > > > > > > On Nov 12, 2018, at 9:31 AM, Filipe Lopes > wrote: > > > > > > > > > > Hi > > > > > > > > > > Is there a listing of such frequencies? Want to avoid those in the > > coming > > > > > contests > > > > > > > > > > 73's Filipe > > > > > CT1ILT CR5E CR6K > > > > > > > > > > Sent from my Huawei Mate 8 > > > > > > > > > > Na(o) Seg, 12 de nov de 2018, 17:28, Mike Waters < > mikew...@gmail.com > > > > > > > > escreveu: > > > > > > > > > > I wish we could get the word out to avoid frequencies like that: > > 1810, > > > > > 1820, 1830, etc. There are almost always AM BC harmonics on those > > freqs. > > > > > > > > > > 73, Mike > > > > > www.w0btu.com > > > > > > > > > > On Sun, Nov 11, 2018 at 4:24 PM k1zm--- via Topband < > > > > > topband@contesting.com> > > > > > wrote: > > > > > > > > > > > > > > > Band still down a bit from last week but 4k6fo good sigs now on > > 1830.0 > > > > > from Alim. > > > > > 73 JEFF > > > > > _ > > > > > Searchable Archives: http://www.contesting.com/_topband - Topband > > > > > Reflector > > > > > > > > > > _ > > > > > Searchable Archives: http://www.contesting.com/_topband - Topband > > > > > Reflector > > > > > > > > > > _ > > > > > Searchable Archives: http://www.contesting.com/_topband - Topband > > > > > Reflector > > > > > > > > > > > > > > > > > > > _ > > > > Searchable Archives: http://www.contesting.com/_topband - Topband > > > > Reflector > > > > > > > _ > > > Searchable Archives: http://www.contesting.com/_topband - Topband > > Reflector > > > > > > -- > > 73 - Petr, OK1RP > > -- > > B: http://goo.gl/Fd2JhJ > > G+: http://goo.gl/w3u2s9 > > G+: http://goo.gl/gP99xq > > _ > > Searchable Archives: http://www.contesting.com/_topband - Topband > > Reflector > > > _ > Searchable Archives: http://www.contesting.com/_topband - Topband > Reflector > _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: WB6RSE Flag type loop question
David, The NEC-4.2 engine appears to give very good results with buried and close-to-ground wires (the NEC-4.1 engine compares favorably, too). It is instructive to read N6LF's July/August 2016 QEX article on his modeling efforts with buried and close-to-ground wires. You can get Rudy's article at http://rudys.typepad.com/files/qexjul-aug-2016-bog.pdf. Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: WB6RSE Flag type loop question
Joe, > However, the Waller Flag is a dual loop that trades off signal for > pattern. I agree. But I believe it's gain is very low mostly because it's made up of electrically very small loops. A very small loop has its main lobes in the plane of the loop - not perpendicular to the plane of the loop as in a quarter-wave-on-a-side loop in a Quad antenna. When a very small loop is mounted horizontally, there's a null in the pattern towards the ground. So even though it's mounted horizontally, it is less susceptible to the effects of the ground. > The LOG is a horizontally polarized antenna nearly on the "boundary" > where the horizontally polarized signal goes to zero. The better > the ground (higher conductivity), the worse (lower) the signal level > from the LOG (thank you Dr. Maxwell). I also agree with Dr. Maxwell. But a very small loop mounted horizontally is not like a big antenna mounted horizontally. And Nick is correct - KK5JY shows a two-loop system farther on down - it's kind of approaching a horizontal Waller Flag. Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: WB6RSE Flag type loop question
Note that the KK5JY antenna is a single loop, not a double loop as G3UNA referenced. > That's a terrible RX antenna. Did you see the losses?! > Minus-forty-something dB on 160. That gain value is in the neighborhood of what a Waller Flag does. Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: low inv-vee
Some of my best, and easiest, 160 DX has been to the Antarctic area and surrounding islands with a coax fed 160 inverted V with the apex at 60' and the ends at 3'. Apparently NVIS into a duct with little attenuation since it rarely took more than a coupleof calls. Im also on a hill in the country here in NH. Carl. - Original Message - From: "Jeff Wilson via Topband" <topband@contesting.com> To: <topband@contesting.com> Sent: Wednesday, March 28, 2018 3:31 PM Subject: Re: Topband: low inv-vee I have always used an 80m inverted-vee (66.6 ft per side) with apex at 50ft at top of a yagi-free tower attached to a steel workshop and fed with 450 ohm ladder line and shorted at the tuner in the shack to work as a top loaded vertical (35ft is actually vertical, rest of the feedline mostly hortizonal 3ft above a steel roof! Just worked JA8EAT with 100W on March 12 at 1040Z (thanks Yaz for LOTW confim and number 131 QSLd on topband...138 worked in 10 years). No 160m amp hereyet. Use 16 radials (100-130ft) and temporary winter 600ft Beverages and 200ft Bogs for RX. Helps being on a hill in the country as well. I always feel loud in the ARRL contests to the West Coast and KH6, but usually have to wait past 0300Z to work any EU even though I hear them at my sunset. So are the others (Brian?) talking about a true coax-fed 160m inverted-vee? If so, I'm interested! Jeff VE3CV On 3/28/2018 12:00 PM, topband-requ...@contesting.com wrote: Message: 4 Date: Tue, 27 Mar 2018 19:26:41 + From: Brian Campbell <ve3...@hotmail.ca> To: Carl Luetzelschwab <carlluetzelsch...@gmail.com>, "topband@contesting.com" <topband@contesting.com> Subject: Re: Topband: low inv-vee Message-ID: <cy4pr12mb18627341f91e72b246d5c847ff...@cy4pr12mb1862.namprd12.prod.outlook.com> Content-Type: text/plain; charset="iso-8859-1" I put up a 1/2 wave Inverted V ( each leg is about 140' ) for 160M in January of this year just so I could do inband SO2R in the CQ160 CW contest. It has its apex at 40' and the ends are at 5'. I would have been very happy to just work any East coast stations during the contest but I found that I was being called by stations from as far away as California down into the Caribbean and everything in between. This morning I worked Luke ( VK3HJ ) on my Inverted L here at 1110z ( SR-5 min ) and we exchanged Q5 reports - nothing unusual. Then at SR he disappeared into the noise. Again nothing unusual. After a java refill I came back into the shack and could hear NA stations calling and working him but he was still NIL - not even a single ping could be heard on the Inverted L. Just for fun I switched over to the Inverted V and there he was 539 to 549 - a real booming signal almost as loud as when we worked earlier when I gave him a 559 on the Inverted L. Now it was SR+28 min so when there was no one coming back to his CQ's I called and I almost fell out of my chair when he came back to me. No we didn't make the QSO as he didn't get my full call but the fact that he heard anything is amazing. Had I been running more than 100 watts I have no doubt we could have finished the QSO. So the Inverted V definitely stays up. Carl I am a believer :-) 73, Brian VE3MGY --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus _ Topband Reflector Archives - http://www.contesting.com/_topband --- This email has been checked for viruses by AVG. http://www.avg.com _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: 160m polarization and elevation angles
Mark, > I learned that polarization is not predictable after the first ionospheric bounce. Theoretically, polarization is well-defined as an electromagnetic wave progresses thru the ionosphere. What's important is the "limiting" polarization at the entry and exit points of the ionosphere, and our job is to best match our antennas to the limiting polarization to couple the most energy into the ordinary wave or the extraordinary and couple the most down-coming energy into our receive antenna. On 3.5 MHz and higher, the limiting polarization is essentially circular, so your antenna's polarization is not real important as both waves propagate with similar absorption and refraction. But on 160m, because of being close to the electron gyro-frequency, the extraordinary wave suffers significantly more absorption. Thus you better make sure you couple the most energy to the ordinary wave on 160m - which is vertical for those at mid to high latitudes. It would have been great to have had the OH8X 160m Yagi up for a long time so RBN could have been used to compare it to nearby vertical antennas. It would have shown how much of this theory is applicable in the real world. Of course the limiting polarization will vary as the ionosphere varies diurnally and day-to-day. But still, in general, most of us at mid to high latitudes should use vertical polarization on 160m. For those near the equator (like the W4s), when they work 160m long path to the southeast thru southwest, their entry and exit points are near the equator, where horizontal polarization should be optimum. Those stations down south using HWFs (horizontal Waller flags) for receive seem to hear long path very well. It would be interesting to see what happens if they used horizontal antennas for transmit. Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: 160m polarization and elevation angles
Polarization - As Jerry K4SAV stated, the electron gyro-frequency plays an important role on 160m since our ionosphere is immersed in a magnetic field - it also affects ionospheric absorption and refraction. For those of us at mid to high latitudes, vertical polarization on 160m is *theoretically* optimum since it couples the most energy to the limiting polarization at the entrance to the ionosphere. I don't understand Mark K3MSB's comment about the polarization terms disappearing unless it has to do with that fact that the polarization going up to the ionosphere has nothing to do with the polarization going thru the ionosphere (which is dictated by the ionosphere). Elevation angles - Ray tracing shows that elevation angles up to about 10 degrees are E hops since there is still enough E region ionization at night to refract 160m. I don't know how important these E hops are - probably okay for short distance, but the losses (absorption and ground reflection) add up quickly for the longer distances. Above 15 degrees or so we get F hops. From 10-15 degrees is where ducting occurs in the electron density valley above the nighttime E region. Ducting in the valley likely requires shallow angles. But when a signal gets dumped out of the duct, that suggests a higher down-coming angle. K4SAV said it best: ". . . and the real world on 160 is very complicated." Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: low inv-vee
Pete N4ZR said one option was to "Suspend inverted vees for 80 and 40 from the top of the rocket launcher (right under the tribander)." Gene AD3F commented on low inv-vees: "From what I've read on Topband and TowerTalk over the years, a low Vee as you're proposing is likely to be a cloud warmer." Yes, a low inv-vee will radiate more energy at the higher elevation angles. But it still radiates energy at the lower elevation angles that are useful for longer distance contacts. For example, a 160-Meter inv-vee at an apex of 45 feet is about 10 dB down (approx 2 S-units) at an elevation angle of 15 degrees compared to a quarter-wave vertical over average ground. For the CQ 160M CW contest in January 2017, I used a 160-Meter inv-vee at 45 feet, with the last third of each end running horizontal and bent 90 degrees from the main portion to fit on our property. Yes, it's a compromise antenna, but I worked 44 states (missed ME, ID, NE, AK), 7 Canadian provinces and 17 DXCC entities (mostly Carib, Central Amer and South Amer, with some EU and a North Africa). My amp at 800 Watts certainly helped, along with a Shared Apex Loop array for receive. I wasn't first in most pile-ups, but perseverance got the job done most of the time. So don't count out a low inv-vee if you have trouble putting up something better. The inv-vee is relatively easy to erect and it's efficient in terms of not needing a ground system. Of course an 80-Meter inv-vee at 45 feet will be better than a 160-Meter inv-vee at 45 feet, as it's twice as high in terms of wavelengths. Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: TN5R to start tonight on TB
they are listening via SDR! 73 Carl SM6CPY 2018-03-13 7:00 GMT+01:00 uy0zg <uy...@mksat.net>: > > Victor ! > > People without really RX must here be quiet ! > > Nick, UY0ZG > > Victor Goncharsky via Topband писал 2018-03-12 21:54: > > The problem of pile-up distribution is even more complex since there >> will be four simultaneous African DXPeditions 3C, TJ, TN and TY. >> Therefore some coordination between team leaders is needed. The good >> example of almost perfect solution was VK0/FT4J case. >> >> >> Понедельник, 12 марта 2018, 18:22 UTC от John Farrer via Topband < >>> topband@contesting.com>: >>> >>> Jose >>> 1824 occupied every day by 9M0W pile up till their SR 2240z. Please give >>> us another frequency to monitor for TN5R. >>> 73 John G3XHZ >>> >>> Sent from my iPhone >>> >>> On 12 Mar 2018, at 14:32, John Farrer via Topband < >>>> topband@contesting.com > wrote: >>>> >>>> Thanks Jose. Many of us monitoring 1824 last night. I stayed up till >>>> 0300z but nothing heard. Will you be on tonight? If your signal is not >>>> picked up by rbn can you please cq at least at the beginning of each hour >>>> so that we can all monitor? >>>> 73 John G3XHZ >>>> >>>> Sent from my iPhone >>>> >>>> On 11 Mar 2018, at 11:34, Jose Ramon < jr.hie...@gmail.com > wrote: >>>>> >>>>> We'll start tonight on top band from the beautiful Congo coast. 880 ft >>>>> (270 >>>>> m) Beverages set to NW, N and NE. An additional steerable diamond shape >>>>> loop is attached to the rx aerials control box so any station can >>>>> choose >>>>> among 4 directions from 160 to 30m. Noise level is not bad on the 18m >>>>> high >>>>> inverted L. >>>>> >>>>> Hope to log you all, conditions permitting. >>>>> >>>>> 73 es GL >>>>> Jose, TN/EA7KW. >>>>> _ >>>>> Topband Reflector Archives - http://www.contesting.com/_topband >>>>> >>>> >>>> _ >>>> Topband Reflector Archives - http://www.contesting.com/_topband >>>> >>> >>> _ >>> Topband Reflector Archives - http://www.contesting.com/_topband >>> >> > _ > Topband Reflector Archives - http://www.contesting.com/_topband > _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: (no subject)
2018-01-12 16:41 GMT+01:00 Hans Hjelmström <sm6...@hjelmstrom.se>: > Hallo Calle > > They are all on computer to computer FT8 mode ..Signals not being heard by > operator. > Ham radio is ,,,no more only computer doing the job,and all can > do something else,while computer get log filled. > Sorry but same indications as on 50 mc last summer. > Have fun Calle and hope ,,( but guess no way ) it will change back > to dx-ing by challenge of fixing great antennas and to HEAR the other > station > you work > Kind Regards and Gott Nytt År > > SM6CVX Hasse > > > > 12 jan 2018 kl. 16:32 skrev Carl Jonsson <carl.jonss...@gmail.com>: > > > > If everyone is checking rbn and dx spots and not calling cq, there is no > > activity. > > 73 Carl SM6CPY > > _ > > Topband Reflector Archives - http://www.contesting.com/_topband > > _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: (no subject)
Agree Hasse! I have not seen many real dx-ers spotted on FT-8 though. I think they´re just watching their computers. This morning, the only station I heard was VE6WZ who called cq. He was heard for 2 hours peaking 599 so there is nothing wrong with the condx! Gott Nytt År! Calle -SM6CPY _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: (no subject)
If everyone is checking rbn and dx spots and not calling cq, there is no activity. 73 Carl SM6CPY _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: (no subject)
I remember working Robin, VK6LK, almost every evening on 3.7 SSB together with SM6DOI, SM7CRW, SM4AAH and many others. He always came up around 9 pm local time, his sunrise. After that I qsy´d to top band and worked VK6HD on cw. That was back in 1985. The good old time! SM6CPY _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: duo-band 80/160 inverted-L
Thanks to a big oak tree, I have used a homebrew 80m trap (large diameter B Miniductor and high voltage doorknob caps) at the top of my 80m quarterwave wire vertical, and a wire at the top of the trap sloped down to a tree by the house to achieve 160m resonance. I have two 60-foot elevated radials and two-120 foot elevated radials. It has worked very well over the years. I also have a small Miniductor coil at the bottom of the vertical wire so I can change from 80m to 75m using an alligator clip to short out turns for 75m operation. Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: greyline forecast for 80m
Hello Kris N5KM, Thanks for the clarification. 80m is a different story. Yes, we can predict greyline propagation on 80m (I assume when you say greyline propagation, you mean propagation along the terminator). And our predictions say there is still significant loss along and near the terminator on the low bands. Simply put, absorption is proportional to the product of electron density times electron-neutral collision frequency - so as we progress from day to night, absorption moves up from the D region to the lower E region. There is still a prohibitive amount of absorption along the terminator on the low bands. What I and others believe is that what really happens is the RF takes a short cut across the dark ionosphere, where absorption is minimal. The RF gets far enough away from the terminator to minimize absorption, but not far enough away to look like it's not greyline. Thus the importance of the greyline is to put both ends of the path in or near darkness. For a great article on 80m greyline, read Ed N4II's article in the Nov/Dec QEX titled "Gray Line Propagation, or Florida to Cocos (Keeling) on 80m". I have written about the problems with "greyline propagation" numerous times, but N4II's article is more elegant! So can we predict this alternate explanation of greyline? Unfortunately, no - as it involves two great circle paths joined by a skew point. Having said that, many years ago Rod VE7VV developed a DOS program to address these skewed paths. I am not familiar enough with it at the moment to offer any comments. I believe Bill W4ZV has used it more extensively. One comment - the output of this program appears to be in terms of a monthly median, since the model of the ionosphere in our prediction programs is a monthly median model. In other words, VE7VV's predictions say something like a signal will be so many dB above 0.5 uV on a percentage of days. Unfortunately, we do not know which will be the good days. Bottom line - keep you butt in the chair at the appropriate times. Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: greyline prop forecast
Kris N5KM asked about greyline propagation predictions. Since his question was posted to the topband reflector, I assume he's only asking in relation to 160-Meters. We do not have any reliable propagation predictions for greyline on 160m. In fact, we really don't have any reliable propagation predictions for any time on 160m. In other words, we do not know in advance what night is going to be good and what night is not going to be good. The best thing to do is know the common darkness times between you and your target, and know sunrise and sunset times at both ends of the path. Make sure you're on when it's dark and make sure you're on around the appropriate sunrise/sunset times. I agree that it would be nice to know when 160m is good, but we're simply not there yet. My guess is we will not even see this in our lifetimes as there is no continual data being taken in the lower ionosphere to gives us clues as to what's going on. So get on and enjoy the magic of topband when it happens. Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: Echo on 160m
Bruce K1FZ said: "I have noticed that there appears to be a link between the start of an aurora and long path 160 meter openings." Others have noted this interesting effect. The only physical tie between the two that I'm aware of is that a spike in the K index can initially improve the electron density valley that is above the E region peak in the nighttime ionosphere, resulting in a better chance of ducting. This comes from a paper by Zhang and Kamide in JGR in 2004 (they just reported their results, but didn't tie it to amateur radio propagation - heck, they might not even be aware of amateur radio!). I'm not saying this is exactly what happens, just that it *may* explain the link between the start of an aurora and long path 160 meter openings. As for the echoes that started this thread and aurora, one respondent wondered about the velocity of propagation of the RF slowing down due to a back scatter mechanism. Ionosondes report virtual height (not true height) because they assume the speed of light for the vertical incident RF. But as the RF goes up in the ionosphere, the group velocity decreases as the index of refraction approaches zero. If these echoes are of Earthly origin, then the appropriate plasma frequency could decrease the group velocity and contribute to the echo mechanism. Just speculation. Having said all this, right now I think Andy G4PIQ's comments are most appropriate for the echoes - unless there is some data and physical mechanism that says otherwise. Of course this is the problem with many of these unusual occurrences - we don't have enough relevant data with respect to the ionosphere or whatever - just observations of an interesting happening. Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: west coast in the mornings
Hi guys and gals, After walking Snoopy and going out for breakfast this morning, I got back on 160m around 1320z (8:20 AM local here in Ft Wayne - about a half hour past our sunrise). Between 1324z and 1340z I worked AZ, CO and OR with decent signals on my SAL-20 Shared Apex Loop. I also heard quite a few other West Coast stations, but they kept CQing in my face. It could be they have a noise problem or it could be a propagation issue (since we don't fully understand all the interesting things that happen on 160m). But it also could be those stations were listening to the west with their directional receive antennas, not towards the east since it was daylight here. If this was the case, be sure to take a listen back towards the east every once in a while. With the Sun in the southern hemisphere, ionospheric absorption is minimal on the mid to high latitude northern hemisphere paths. I hope to work some of you tomorrow morning! Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: good 160m propagation when the A index is elevated
hello to everyone, With respect to Wolf DF2PY's comment about very good propagation on polar routes when the A index and the solar wind speed are elevated, our understanding of what makes 160m tick is lacking. In other words, "stuff happens". Having said that, there have been similar reports of good propagation on 160m at high latitudes when the K index spikes up. A process that could explain this is tied to changes in the E region and lower F region at elevated K indices. When geomagnetic field activity increases, the atmosphere's electric field (measured in terms of mV/meter) increases. When this happens, the electron density valley above the E region peak can become better developed (deeper and more vertical extent - which would eliminate transits through the absorbing region and eliminate ground reflections). This process comes from a 1984 paper in the Journal of Geophysical Research. It is only a model - I'm not aware of any measurements to confirm that this happens. So "buyer beware". All I can say is - it makes sense. Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: what's in store for 160m
About a week ago Wolf DF2PY posted a message here commenting on the recent adverse levels of geomagnetic field activity and how it will now change for the good - giving us good 160m propagation. We'll certainly see less geomagnetic field activity as we move into winter, but there's another issue we should be aware of. The Sun's magnetic field is weakening - probably to the lowest levels in our lifetime. With a weak solar magnetic field, more galactic cosmic rays will be able to get into the Earth's atmosphere. We are now seeing unprecedented high neutron counts (neutrons are one of the by-products of cosmic rays) Since galactic cosmic rays are mostly *very energetic* protons, they can get down to low atmospheric altitudes, causing collisional ionization in the D region (and lower E region). A cursory estimate using cosmic ray ionization rates confirms more ionization in the lower atmosphere. 160m is not very tolerant of more absorption, so we may see an adverse effect of the weakened solar magnetic field. Many of us think that "solar min is solar min is solar min". But maybe a solar minimum can be too deep for 160m. A good question to ask in the early 2020s will be "how was 160m?" So stay active on 160m and let's see what happens. Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: inv. L
Art I use two 65' verticals on 40/80/160. HALF WAVE tall (electrically) and spacing on 40m with LC network at the base to tune...QUARTER WAVE tall on 80 with same spacing and EIGHTH WAVE tall and spacing on 160m. Both verticals are fed in phase on 160 now but I have plans to add an LC phaser that should allow for some directivity. Current pattern seems to be omni with the verticals being so close to one another. I did try inserting a delay line into the scheme with some (2-3 db) directivity seen and may continue to experiment with that angle until I build the LC Phaser. AG6X -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Art Snapper Sent: Monday, October 17, 2016 8:17 AM To: 160 Subject: Topband: inv. L I was considering adding a second vertical element to my 160 inverted L. This one would be roughly a quarter wave tall for use on 80. I tried modelling in Eznec, but wasn't comfortable with the results. I may have screwed it up. Has anyone tried it for real? Is it a big compromise on either band? Would a switch at the feedpoint have any benefit? My inverted L has about 50 radials. 73 Art NK8X _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: midnight peaks
Yes, you have to distinguish between sunrise enhancements and this so-called midnight peak. The 17 November 1996 topband posting that I referenced from DJ8WL told of XZ1N on 1825.5 KHz at 2130 UTC. XZ1N's sunrise would be around 2345 UTC on Nov 17. That's 2 hrs 15 min before XZ sunrise. So this report does not look like a typical sunrise enhancement. Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: midnight peaks
Over the years I have seen a few comments with respect to signal peaking around local midnight. If you search on "midnight signal peaking" in the topband archives, you should come up with four results. The one from DJ8WL back in Nov 96 appears to be the only relevant one that I found. I don't know if this is somewhat consistent or just coincidental with the variability of the ionosphere. Regardless, any physical explanation likely involves D region chemistry. Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: 160m arrival angles
BIll (AA7XT), There's some (but not much) measured data at HF of arriving elevation angles (for example, Wilkins et al, Epstein et al, Utlaut et al, Wilkins again et al, and Hallborg et al). But I've never seen any measurements at MF. The only paper that comes close (at least that I'm aware of) is by LaBelle. He measured arriving polarization from 50 KHz to 5 MHz. The only thing I can add are results of doing ray traces of the ordinary wave (the extraordinary wave is heavily attenuated on 1.8 MHz) with electron-neutral collisions and the magnetic field included. There appears to be three ranges of angles for propagation on 160-Meters at night. Low angles (roughly 0 to 15 degrees) give E hops. Medium angles (roughly 15 to 20 degrees) can give ducting. Higher angles (roughly above 20 degrees) give F hops. Whether ducting on 160-Meters occurs likely depends on the factors tied to the magnetic field. For a picture of these ray trace results, go to http://k9la.us. Click on the "160m" link on the left, and look at the "ray tracing on 160m" file at the top. As for E hops, it's tough for most of us to put lots of energy at very low elevation angles - but guys like VE1ZZ with take-offs over salt water may be able to take advantage of these very low angles. Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: antennas close to ground
Mike W0BTU commented: "But I thought that it was a well-established fact that NO antenna modeling software does well with antennas close to the ground". Yes, I believe that's true with the NEC-2 computational engine. The NEC-2 engine is readily available to the public. The NEC-4 computational engine addresses antennas very close to ground, buried antennas and antennas connected to non-perfect ground. The NEC-4 engine requires a license from Lawrence Livermore National Labs - it is $300 for US Non-commercial entities. This does *not* include the antenna analysis software. N6LF used NEC-4.2 (with EZNEC Pro4 v6) in his article that I recently cited, and his results were very good for what he simulated and measured (one buried antenna, one antenna very close to ground and a vertical wire with a ground rod). Of course just having the NEC-4 engine doesn't guarantee success, as N6LF pointed out. You must have an accurate model of your ground conditions, you must obey the wire rules, you must have accurate dimensions for the antenna, and if it's wire you should include the insulation, too. That's my two cents worth. Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: 2 element vertical for 80m with 1/8wavelength spacing
John and fellow Topbanders I'm running a similar setup...and have my two 65' verticals spaced at 71'. I have custom matching circuits that allow me to use the verticals on 160m (inductively base-loaded) at 1/8 wl spacing...80m (1/4 wl tall) at 1/4 wl spacing...and 40m (1/2wl tall) at 1/2 wl spacing. The antenna is basically OMNI directional on 160 but offers up to 20db F/B on 80 @ 3-4db gain and even larger F/B and gain in 40. Each vertical is aluminum tubing tapering from 4" at the base to 1" at the top and sits above 100 radials. Don, AE7H, was kind enough to send over schematics and magazine articles featuring the "Elsie Phaser"...that implements a variable capacitor, a variable inductor and a DPDT relay. He claims big F/B and gain when tuned vs the traditional delay line approach that's featured in John's (ON4UN) book. I'm eager to get moving on that project and have it ready for the coming DX season. Contact me if you'd like details on this gadget. I love the "tri-band" antenna and maintaining it involves much less drama than the two element 75m yagi I had at 95'. 73 Carl AG6X -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of John Kaufmann Sent: Tuesday, April 19, 2016 5:26 PM To: 'topband' Subject: Re: Topband: 2 element vertical for 80m with 1/8wavelength spacing I also use a vertical phased array with 1/8-wave spacing on 80m. I did this because of limited space. Like PE5T describes in his post below, I used the method in ON4UN's book and originally described in a series of articles by K2BT in Ham Radio magazine (no longer in publication) in the 1980's. I designed my own custom L-C circuits for phasing and matching. I don't think there is a simple plug-and-play solution that would provide good performance at close spacing like this. As Kees says, the impedances at close spacing are low and you have to work at keeping losses small. Otherwise you don't realize the theoretical gain. This means a large radial system. I use over 100 radials per element. The theoretical gain of my system is about 4 dB. This is about what I see in practice comparing my 2-element array to a single reference vertical. My array is optimized for the low end of the 80m CW band and I get up to 25 dB F/B. I still see some F/B as high as 3700 kHz but by 3800 kHz it is omnidirectional. The SWR is close to 1:1 at 3500 kHz but goes up to 2:1 around 3550 kHz. I use a separate network optimized for 3800 kHz for SSB, but 98% of my operation is CW. The system does work very well provided you have a good ground system. I have worked 333 countries on 80m with this system from an average suburban location. I also retune this system for 160m operation, but that is another story. 73, John W1FV -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Kees Nijdam Sent: Tuesday, April 19, 2016 12:07 PM To: Filipe Lopes; topband Subject: Re: Topband: 2 element vertical for 80m with 1/8wavelength spacing Hello Filipe, Yes, I have such a system. Cost me several days to optimize it. My comments. The 2x157 and 39 degrees phasing lines are based on very good earth systems (2-3 Ohm). When your radial network is 5 Ohms, it is a different story. That is because the driving impedances are very low (in my case 19,27+j21,14 Ohms and 13,86-j15,73 Ohms) and the influence of the earth system on these impedances is big (a 1/4 lambda system is not that critical) If you do not know the impedances of your verticals, the only way to go forward is to measure the self impedances and the coupled impedances. After that you can follow the calc ulations in ON4UN's book and software. My system is optimized for 3510 kHz and with a signal source at 400 meters I found a front to back ratio of 24 dB for this frequency. On 3500/3520 kHz is was 20 dB, on 3540 kHz only 10 dB and higher in frequency the antenna becomes more and more omni directional. However, the swr was OK over the whole band, also on 3800 kHz. So it can be used on 3800 kHz but without directivity. You need a very good radial system and to decide for CW or SSB . My advice: better and less critical is to increase the distance between the verticals with a few meters. Is it worth the effort? Yes I think so. I have one vertical permanent and during the winter I install the other. The few dB extra gain is good but I was also very happy with the system as RX antenna. I have it oriented north-south and it is nice to hear KH6AT over the south pole and not over the north pole.. Kees, PE5T _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Activity today
T32CO and Eugene RA0FF were both booming in this morning here in San Diego. Nice to see the activity from these guys. Carl AG6X -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of David Raymond Sent: Monday, March 14, 2016 10:10 AM To: TopBand Subject: Topband: Activity today Topbanders. . . while the band has seemed to be in the doldrums there was some nice activity on the band today. 5J0P and T32CO were QRV. They seemed to be hearing well as I was able to work them both with 100 watts. However, the big surprise of the morning to finding Eugene, RA0FF, CQing with a 559 signal with no takers. He answered my call running a KW immediately. He peaked an honest S6 near my SR. Robert, DU7ET, was also QRV as was Ross, 9M2AX. Both were too weak to call but partially copyable for moments. Cocos-Keeling and Heard will both be big challenges from here in Iowa. 73. . .Dave, W0FLS _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: Stew
Let me see if I understand this. Someone is complaining that other ops are not upholding the concept of 160-Meters being the "gentleman's band", and that same person who is complaining uses cut letters for profanity and runs 2 kW? Joel, maybe both of us need to stay more up to date. See you in Houston next weekend? Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: RDF in the real-world
Rick N6RK said: > In this webinar, it was asserted (without explanation) that > for every 1 dB increase in RDF, you get 1.5 to 2.0 dB > improvement in S/N ratio. I've never heard that before > and don't even see how it makes sense. Actually, I don't > even know how you can make generalizations like that > unless you are describing a theoretical QTH with uniform > isotropic noise. I'd like to believe this is true. > Can someone educate me as to why I should believe this? I believe the issue is that RDF is a theoretical calculation comparing the main lobe gain to the overall average gain. The overall average gain essentially results in the assumption that noise is coming in uniformly from all azimuth angles and elevation angles. But in the real-world man-made noise doesn't abide by this assumption, and neither does atmospheric noise. As for atmospheric noise, there was an interesting article about the directional characteristics of atmospheric noise in Radio Science in 2002 (by Prof Chris Coleman, who is a VK5 but I don't remember his call at the moment). Chris even did a plot for me of atmospheric noise coming into W4ZV's QTH on a winter morning, and it was obvious that antennas with the same (or very similar) RDF could provide different SNR improvements depending on where the nulls in the pattern were. I can't vouch for JC's numbers (his numbers may be QTH specific), but the concept is believable since the theoretical assumption of isotropic noise falls apart in the real-world. My BOG *at times* gives much more of an SNR improvement than the SAL-20 (using measurements on a calibrated S-meter) in spite of the small difference in RDF between the BOG and SAL-20. Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: What have I done?
Thanks for the response and the calculations Don. Lots of offline responses to my query. The antennas use 90 radials 40' to 150' with the average at 66' Your option B is the way I configured the L network and your numbers are very close to mine. The second variable cap was set aside to use the smaller one. I'm going to try and roll my own inductor and apply a 70pF cap to gnd or variable cap to resonate Wish me luck Thanks Carl AG6X Sent from my iPhone On Feb 14, 2016, at 11:56 PM, "Don Kirk" <wd8...@gmail.com<mailto:wd8...@gmail.com>> wrote: Hi Carl, Does not appear anyone has answered you, so let me give it a quick shot while between flights in Japan. I'm somewhat confused with your final L network configuration because you mentioned one capacitor, and then a second capacitor without mentioning if you still had the first capacitor in your configuration, etc. You also did not mention what L network configuration you used (see below). Therefore I started from scratch to see what a 64 foot vertical wire would look like at 7.050 Mhz to see what kind of L network would be required to convert its impedance to a pure 50 ohms resistance. Using EZNEC demo, I approximate a 64 foot vertical wire on 7.050 Mhz has an input impedance of approximately 1274 +j1436 ohms when just using a ground rod with medium soil (because this antenna has such a high input impedance it really does not matter what I use for ground conductivity). Then using an online L network calculator I come up with the following two different L network configurations you could use to match to a 50 ohm resistive source. L network with inductor between bottom of 64 foot vertical and ground. L = 10.18 uh C = 59.9 pf L network with capacitor between bottom of 64 foot vertical and ground. L = 8.5 uh C = 67.6 pf Not sure what L network configuration you used, but does it sound like I closely replicated what you have based upon one of the above mentioned L network configurations? If not, then please better describe your configuration. Please advise so we can better answer your question, and hopefully I have not messed something up with my quick analysis/approximation. Don (wd8dsb) On Sat, Feb 13, 2016 at 4:53 PM, Carl Braun <carl.br...@lairdtech.com<mailto:carl.br...@lairdtech.com>> wrote: I have revised my question to correct the length of the antenna in question Topbanders In the past, I've posted some questions related to making my 80 meter verticals (64' tall ground mounted) work on different bands. The pair is spaced at ¼ wl on 80m and then I switch in base loading to resonate the same pair on 160m which are then effectively spaced at 1/8 wl. Now I want to make them work on 40m which would have them resonate as ½ or 5/8 wl and would have an effective spacing at ½ wl. So this is what I did...I installed an L network off of the vertical effectively tuning a 64' stick of aluminum to 7.050. It took me a couple of tries as the first 1500pF (monster) variable capacitor wouldn't get down low enough to get me flat. I had another 50-150pF Johnson variable cap available so I tried that and got the antenna to tune to 46 ohms at j+0.Inside the shack I see 1.0:1 Vswr from 7.000 to 7.290...wow! I measured the cap and it came to 70pf. My cheapie Chinese meter doesn't register anything on the L scale but I have 7 turns on a 3 ½" inductor. The full coil is 33 uH at 25 turns so I estimate 8-12 uH of inductance. But what have I done? Have I resonated a ½ wl antenna or have I resonated something else like a 5/8 wl antenna with the added inductance? I plan on treating them as ½ wl spaced phased verticals on 40 and feeding them with equal lengths of ¾ wl feedlines for broadside phasing and then adding an additional 2/4 wl to get my 180 degree shift for end fire. Please share your comments. thanks Carl de AG6X _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: What have I done?
Topbanders In the past, I've posted some questions related to making my 80 meter verticals (64' tall ground mounted) work on different bands. The pair is spaced at ¼ wl on 80m and then I switch in base loading to resonate the same pair on 160m which are then effectively spaced at 1/8 wl. Now I want to make them work on 40m which would have them resonate as ½ or 5/16 or 3/8 wl and would have an effective spacing at ½ wl. So this is what I did...I installed an L network off of the vertical effectively tuning a 64' stick of aluminum to 7.050. It took me a couple of tries as the first 1500pF (monster) variable capacitor wouldn't get down low enough to get me flat. I had another 50-150pF Johnson variable cap available so I tried that and got the antenna to tune to 46 ohms at j+0.Inside the shack I see 1.0:1 Vswr from 7.000 to 7.290...wow! I measured the cap and it came to 70pf. My cheapie Chinese meter doesn't register anything on the L scale but I have 7 turns on a 3 ½" inductor. The full coil is 33 uH at 25 turns so I estimate 8-12 uH of inductance. But what have I done? Have I resonated a ½ wl antenna or have I resonated something else like a 5/16 wl or even a 3/8 wl antenna with the added inductance? I plan on treating them as ½ wl spaced phased verticals on 40 and feeding them with equal lengths of ¾ wl feedlines for broadside phasing and then adding an additional 2/4 wl to get my 180 degree shift for end fire. Please share your comments. thanks Carl de AG6X _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: What have I done?
I have revised my question to correct the length of the antenna in question Topbanders In the past, I've posted some questions related to making my 80 meter verticals (64' tall ground mounted) work on different bands. The pair is spaced at ¼ wl on 80m and then I switch in base loading to resonate the same pair on 160m which are then effectively spaced at 1/8 wl. Now I want to make them work on 40m which would have them resonate as ½ or 5/8 wl and would have an effective spacing at ½ wl. So this is what I did...I installed an L network off of the vertical effectively tuning a 64' stick of aluminum to 7.050. It took me a couple of tries as the first 1500pF (monster) variable capacitor wouldn't get down low enough to get me flat. I had another 50-150pF Johnson variable cap available so I tried that and got the antenna to tune to 46 ohms at j+0.Inside the shack I see 1.0:1 Vswr from 7.000 to 7.290...wow! I measured the cap and it came to 70pf. My cheapie Chinese meter doesn't register anything on the L scale but I have 7 turns on a 3 ½" inductor. The full coil is 33 uH at 25 turns so I estimate 8-12 uH of inductance. But what have I done? Have I resonated a ½ wl antenna or have I resonated something else like a 5/8 wl antenna with the added inductance? I plan on treating them as ½ wl spaced phased verticals on 40 and feeding them with equal lengths of ¾ wl feedlines for broadside phasing and then adding an additional 2/4 wl to get my 180 degree shift for end fire. Please share your comments. thanks Carl de AG6X _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: CQ160
Cq160 is not very interesting for a dx-er anymore. A handfull of european big guns are covering the band with CQ over and over again but they don't seem to hear very well. During the morning hours I can hear a layer of NA and SA stations behind the usual european contest stations who keep CQ-ing test continuously. And it seems to be the same problem in the US. Hope to meet you after the contest! 73 Carl SM6CPY _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Topband Strange Propagation
Don't the new auto tune amps have the ability to retune with a single dit? My old Henry takes a lot more than a dit when retuning from 80 to 160. Hi Carl AG6X Sent from my iPhone > On Jan 17, 2016, at 4:37 AM, "Kenneth Grimm" <gr...@sbc.edu> wrote: > > My take on it was that "the dit marks the spot" either for a buddy or just > as a "public service." While not as annoying as other forms of > transmissions on the DX freq, it still shows bad manners...however, not as > bad as when I forget to engage the split button. Maybe that is why I've > never been nominated for the A1 op award. At least it's why I wouldn't > nominate me. > > 73, > > Ken - K4XL > > On Sun, Jan 17, 2016 at 12:31 AM, Louis Parascondola via Topband < > topband@contesting.com> wrote: > >> I have experienced this single dit when working split on a DX station. I >> wondered if it was some kind of malicious interference of some sort but >> other than what Gary suggested I don't see how it is terribly annoying to >> the point that one would be making any statement by doing it. >> >> >> W1QJ >> >> >> >> -Original Message- >> From: Richard (Rick) Karlquist <rich...@karlquist.com> >> To: Gary <g...@ka1j.com>; topband <topband@contesting.com> >> Sent: Sat, Jan 16, 2016 11:07 pm >> Subject: Re: Topband: Topband Strange Propagation >> >> >> >>> On 1/16/2016 12:10 AM, Gary Smith wrote: >>> >>> There's an odd behavior that we've all heard & that's the "ditter", >>> the person who on the DX frequency sends the occasional dit, not a >>> string, just a dit & then some odd seconds later does it again. I >>> wonder if they do it to bust the chops of someone like me who tries >> >>> KA1J >> >> Some auto tune linears are set up to change bands or sub-bands >> by sending one dit. With peak reading meters, they will also >> display RF out and SWR from one dit. At least this is a lot >> less QRM than tuning up the old fashioned way. In both >> cases, the solution is to select SPLIT before transmitting >> or just tuning. >> >> Most rigs have IF gain this is optimized for phone, which >> means it is way too low for CW. This results in an AGC >> threshold that is way above the rig's internal noise level. >> >> Short of redesigning the rig (I actually did this to an FT-757 >> by adding an IF gain stage), you should use an audio attenuator >> in front of your headphones so the the rig's audio output stage >> clips before the level in 'phones gets too high. >> >> Rick N6RK >> _ >> Topband Reflector Archives - http://www.contesting.com/_topband >> >> _ >> Topband Reflector Archives - http://www.contesting.com/_topband > > > > -- > Ken - K4XL > BoatAnchor Manual Archive > BAMA - http://bama.edebris.com > > "Show me a politician who is poor, and I'll show you a poor > politician." - Carlos > Hank González > _ > Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Palmyra cursed paradise (K5P)
Thanks Doug. Awesome read. Has me wondering about our guys on the island. Maybe the "darkness" of the island has something to do with the S9+ signals we're seeing here in San Diego. Hi. Carl AG6X Sent from my iPhone > On Jan 16, 2016, at 1:26 PM, "Doug Turnbull" <turnb...@net1.ie> wrote: > > Dear OMs and Yls, > The following link was posted me by Don EI6IL and tells a very > interesting story of woe and murder on Palmyra Island going back to the very > discovery of the atoll.Slightly off topic but many of us have illusions > of working K5P so this may be of interest and also add a bit of spice. The > cursed paradise is a good read: > > http://mysteriousuniverse.org/2014/07/the-cursed-paradise-of-palmyra-atoll/ > > > Yes EU feels the W6 pain this time and the poor cousins of EI in DL > and I lands are even worse off than in EI for K5P. At least the EI path is > over ocean and tundra rather than thousands of fellow hams. > > Good hunting. > 73 Doug EI2CN > > > _ > Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: K5P signal strength
At 1040z here in so cal the K5P station went from NIL to 599 on Topband. Maybe someone found the ON button for the amp? Carl AG6X _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: K5P signal strength
K5P announced QRX at 1513...20 minutes after my local SR. Very stron when QRX and being reported by other west coast stations. Now at 1517 still no return with no stations calling. Maybe a Latte break. Carl AG6X -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of K4SAV Sent: Friday, January 15, 2016 7:13 AM To: topband@contesting.com Subject: Re: Topband: K5P signal strength K5P had a big signal around 0900Z this morning. We had thunderstorms and the bands were very noisy but he came in over the top of that. He faded a little later on but still good copy. I worked him at 0800Z up 1 with no pile to bust. The piles have been large close to sunrise but at 2AM local time it was first call, no waiting. He was listening UP during the very early morning hours but a little later switched to listening DOWN. The first day his signal was weak but very persistent. Copy was OK even though he was weak, and I could copy him up to 1 hour after sunrise. That's very unusual here. The piles were huge as you know. The first day he was on 1826.5 listening UP and working mostly NA but he also worked a bunch of JAs. I was wondering how he did that but now maybe I have a clue. Jerry, K4SAV On 1/15/2016 8:11 AM, Les Kalmus wrote: > Apparently, they had problems tuning the Battle Creek Special and were > using a SteppIR vertical the first day. > That's been fixed and was what they were using today. > > It's bad enough they were working JA's during this morning's opening > but I heard them call EU too and was shaking my head. > > Les W2LK > > > On 1/15/2016 7:23 AM, Tim Shoppa wrote: >> Heard very well here in MD from 1120Z-1220Z on my west-facing >> pennant, deep fade at my sunrise to ESP. Working mostly JA's but >> trying for NA. >> (Although >> at least once K5P called for EU!) >> >> Tim N3QE >> >> On Fri, Jan 15, 2016 at 5:48 AM, Carl Braun >> <carl.br...@lairdtech.com> >> wrote: >> >>> At 1040z here in so cal the K5P station went from NIL to 599 on >>> Topband. >>> Maybe someone found the ON button for the amp? >>> >>> Carl AG6X >>> _ >>> Topband Reflector Archives - http://www.contesting.com/_topband >>> >> _ >> Topband Reflector Archives - http://www.contesting.com/_topband > > _ > Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: RFI - 1825.5
Tony I have similar birdies on 160 but my worst one resides at the bottom of the 75m DX window at 3790 or so. It's 5kc wide and sounds like a digital warbler. Some say its a neighbors noisy router that peaks at S9 when I switch to the southwest. My nice neighbor lady with the megawatt solar system just informed me that they ran a horizontal "electric wire" around the top of their half acre dog pen to keep their inbred dogs from launching over the 4' fence. Ugh. Isn't that the same design Marconi used??? I plan on getting my Icom IC91 out with my three element 2m sniffer yagi and start walking the streets tomorrow morning. Wish me luck Carl AG6X Sent from my iPhone > On Jan 15, 2016, at 3:23 PM, "N2TK, Tony" <tony@verizon.net> wrote: > > I have a new RFI problem. It starts somewhat before sunset and lasts until > right after sunrise, 7 days a week. > > It has three frequency peaks - 1817.8, 1825.5, 1828.9 MHZ in the lower part > of 160M. The bandwidth of the worst one is from 1.824.5 - 1826.1. It has a > raspy sound to it. > > I have the general direction so will be taking a walk with a portable radio > tuned to 1825.5. > > It does not seem to be an external night light as none come on this early in > the area that I could find so far. > > Very little signal on the second harmonic 3.651. Similar sounds in the same > direction but not as strong on 1753, 1760, 1764, 1782, 1871, 1883, 1890, > 1902, 1948. Don't know if these are related the ones on the low end of 160M. > > > > > Any ideas what may generate RF at these frequencies that can help me to > shorten my search? > > > > 73, > > N2TK, Tony > > _ > Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Strange propagation
JC hit the nail on the head...lets identify those who are using RHR openly. My preference would be a specific suffix designator that would identify the transmitting station and then let's see if anyone wants to work a RHR on the air. I witnessed a local san diego station working RHR last Christmas via a KH6 RHR station with the implication he was actually in Hawaii. Operators asked about the WX and operating power with the stateside station playing along as if he was truly in Hawaii. QSOs went on and on without any clarification from the stateside operator that signed KH6/x. My suggestion is to determine a suitable (international) suffix designator for RHR stations so we all know who and where the signal is coming from...or NOT. Those opposed to that rationale could be those that enjoy the thrill of deception rather than an honest QSO. What other reason could there be for a station that wouldn't want to use a suffix designator that clearly identifies the fact that their RF origin could literally be from anywhere in the world? BTW, there hasn't been so many posts related to a single topic sincewell, since the first time RHR was discussed on the reflector. This topic has so many posts it constipated my netzero account. Carl AG6X -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of JC Sent: Thursday, January 14, 2016 5:39 PM To: 'TopBand' Subject: Re: Topband: Strange propagation <> The issue is what you do and not what you say If all this new technology is do good , the HRH users should be proud of is and PUBLISH, open publicly and announce proudly . "" I am a HRH user!!! "" However that is far from reality, the main business drive is privacy. HRH warranty nobody will possibly know you are using this fantastic technology. WHY?? Open the list of users, be proud of it! My 100 cents N4IS JC -Original Message- From: Herbert Schoenbohm <he...@vitelcom.net> To: topband <topband@contesting.com> Sent: Thu, Jan 14, 2016 4:54 pm Subject: Re: Topband: Strange propagation Dave, What will happen then is that the RHR gurus will just jack up the rates to take the hams with deepest pockets. Additionally the laws of supply will kick in and more RHR station and others will invest in this scheme to put more stations on the air. As this progresses the value of the entire DXCC program will diminish. There must be some brakes put on this before is is to late. The other night I was thrilled to have an Italian station calling me on 160 only to learn later he was actually on the mainland via an RHR station. Is this the way amateur radio is supposed to trend? Herb Schoenbohm, KV4FZ On 1/14/2016 5:28 PM, Dave Blaschke, w5un wrote: > Look at the situation; There are just a few stateside RHR for rent > locations. As more and more "hams" begin to use these sites to work > DXpeditions, the queue length to access one of these sites will become > hopeless long. JUST A THOUGHT. > > Dave, W5UN > > On 1/14/2016 6:33 PM, Herbert Schoenbohm wrote: >> I have lost my amateur station in three major hurricanes over the >> years here, everything including radios (from water) and antennas. I >> have also rebuilt them a four different locations until I finally >> scrapped enough money together and bought a home next to a large salt >> pond. I have full remote station here but it only functions for >> contest operated by a cliff dweller in NYC who cares not for DXCC >> credit. The problem with the US RHR deals is that it completely >> skews the process as far as the propagation differences across the >> fruited plan. I would love to add to my DXCC totals as I close into >> the 300 mark. USA stations can do this but is it ethical. It sure >> makes money for a pay to play amateur radio scheme. But is it the way >> you want low band Dx-ing to become? I hope not as you only will need >> a computer and an internet connection and everything else that used >> to a worthwhile effort is trashed. >> >> I remember a former 160 meter DX pioneer, Charles O'Brien who >> originally from Illinois used a 1/4 wave bent Marconi and 25 watts to >> work a G station. This is what we are or what we used to be. RHR I >> am afraid is the end of an era were perseverance and not vast amounts >> of QRO muscle and money decided who was on top. That is a shame and >> perhaps to some a disgrace as it really chances everything including >> the respect we have for those who did so much with so little.` >> >> Herb Schoenbohm, KV4FZ >> >> On 1/14/2016 12:43 AM, Dave Blaschke, w5un wrote: >>> I will say this: >>> operating a remote station (for money) owned and managed by someone >>> el
Re: Topband: K5P first night
Herb and Topbanders I, too, heard K5P on TB well after my sunrise here in San Diego...about 25 minutes past SR. In fact, the K5P signal on TB was better than it was on 80M. I witnessed some real QSB fades on 80 and saw none of that on 160. The pile up on 80 was also much less organized than it was on 160...token jammers and such. FYI, on 80 I use two phased 65' verticals and 1/4 wl spacing with a comtek box which was phased SW at Palmyra...I use those same two verticals (in phase currently) with base loading for 160...basically an OMNI on 160. I'll change my phasing tonight that allows me to phase wither SW or NE and usually gets me a db or two toward the direction of interest. Maybe tomorrow I can offer an update on the signals out of K5P vs SR times for the group. Let's all support the guys who are making the K5P DXpedition a success...especially for us TBers. Regards Carl AG6X -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Herbert Schoenbohm Sent: Thursday, January 14, 2016 12:36 PM To: Mike Waters; TopBand List Subject: Re: Topband: K5P first night First night I heard K5P fine one a nice post S/R peak on TB 45 minutes after my SR. Unfortunately the wall from the mainland was non-penetrable. I noticed from the prop chart that the operation doesn't see the wonderful opening I an other Caribbean stations would have from 9:00 to 10:00. Even on 80 CW the ops did a great job an hour or so past my S/R. I know they are concentrating on N/A and I shouldn't try to nudge them on an hour earlier. But this is the constant dilemma with Pacific DX-peditions who watch the Sunrise-sunset charts as the boss. I will also try the EU only attempts at their Sunset but the Euros have an even more difficult problem of only a few minute window at best. If only they could stay on after the EU path is closed for a few minutes or in the alternative set the alarm clock and get one of the top band gurus to light up the path and forget those darn computer generate SR/SS charts for just a moment it would be great. I am going again to the donation page to help a bit with the awesome expenses and put some money where my mouth is. Herb Schoenbohm, KV4FZ On 1/14/2016 4:08 PM, Mike Waters wrote: > Never mind. I just found a web site that said "Palmyra *Atoll*". > https://en.wikipedia.org/wiki/Palmyra_Atoll > All I have to do now is find your 160m operating schedule, which so far > escapes my searches and browsing. > > 73, Mike > www.w0btu.com > > On Thu, Jan 14, 2016 at 1:46 PM, Mike Waters <mikew...@gmail.com> wrote: > >> Milt, are you on a DXpedition operating from Palmyra in Syria?! Of all the >> places! >> >> I should switch my antenna back to 160m and see if we can work you. >> >> > _ > Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Strange propagation
Ed N1UR said "It seems non-trivial to me as to how to maintain these remote stations." My guess is it was someone using the Portland, OR station in the Remote Ham Radio network (http://www.remotehamradio.com/the-stations/). The stations are available for a price. I don't know whose actual station that is - but I'm sure it is someone's home station (just like all the others in the network). Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: placement oc coil
Hello John I, too, have experimented with base and top loading with verticals on Topband. No question about it, the toploading is much better. Just take a look at your feedpoint impedance with the base coil vs any sort of top loading. One point to note, a specific coil that will resonate the base will not provide the same loading if placed at the top...more "coil" will be needed if mounted near the top of the antenna. When I had a single 65' vertical with 90 radials resonated with T wire loading I had a base impedance near 25 ohms...the same 65' vertical with a large EF Johnson broadcast coil at the base gives me close to 10 ohms...ugh! I use the base loading as it provides a cleaner installation vs. overhead loading wires but if I had my druthers they would be top loaded with an 80M trap and "L" wire to resonate on 160. Top load if you can and let us know your results 73 de AG6X -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of w5...@towerfarm.net Sent: Friday, January 08, 2016 3:10 PM To: topband@contesting.com Subject: Topband: placement oc coil Hello to all.I am planning a 60 foot vertical.I am wanting to either place a coil on the vertical for topband.The vertical is a hy-tower.I have base loaded(not very effective) I have toploaded with a single wire(not enough room).I now have plenty of room.So my question. Base load with many radials,60+ top load at the highest with wires? top load with coil? and if this is best where should the coil be placed. thanks to all es 73 john w5jmw _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: W1BB stats before/after 1958 solar max
But that was the best ever solar year on record and very few DX had accesss to the band or were limited to flea power. I was working the "world" on 6M those years which was also a very limited number of countries. Not even G, DL, et but EI and some others were 20-30 over 9 with 5-10W. HB 100W on AM, 6AK5 6J6 converter into a HQ-129X on 40M and HB 4 el at about 15' out on LI NY well away from the ocean. I met Stu many times after 64 when I was at National as he was a regular visitor and got me interested in 160 but I didnt have a decent antenna or power until the late 70's and no Beverages till the mid 80's. After that it was fun. Carl - Original Message - From: "Tim Shoppa" <tsho...@gmail.com> To: "topBand List" <topband@contesting.com> Sent: Monday, January 04, 2016 12:55 PM Subject: Topband: W1BB stats before/after 1958 solar max From http://www.w8ji.com/160%20History/bul0263.pdf : Number of different DX stations worked by W1BB on topband each winter: 1954/1955: 19 1955/1956: 26 1956/1957: 20 1958/1959: 4 1959/1960: 5 1960/1961: 11 1960/1962: 27 Tim N3QE _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2015.0.6176 / Virus Database: 4489/11324 - Release Date: 01/04/16 _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: Detuning a nearby Tower
Hello Topbanders I have a two element array 1/8wl away from my 90' Skyneedle tower with Telrex yagi atop. I want to electrically isolate this tower from the array by dropping a shunt wire from near the top of the tower down to the panel where I have an MFJ model 931 artificial ground (input) that then connects to my earth ground. Tuning the 931 to eliminate the RF field strength induced from the array results in an invisible tower to the array...in theory. In the past, I have used a similar method to shunt feed the tower on 160 ala vacuum variable tuning and radials. When I tapped the tower I found a sweet spot at the ~70' level on the skyneedle that provided a fairly good 42 ohm match and, once tuned, it worked pretty well on TX. Here is the concern...I would prefer to use this same tap point for my detuning experiment as it seems to make sense that the same point would induce the max coupling from the array...or at least be a good starting point. ON4UN and others have implied that, when detuning a tower, you should tap it at the TOP of the tower structure and not ¼ of the way down from the top like I's considering. Should I just run the 3' gamma arm off of the very TOP of the tower at the 90' level then down or am I better off tapping the gamma arm at the 67' level as I did when I shunt fed the tower for TX on 160? Comments? Carl _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: 1/2 wl verticals and spaving
Rick Thanks for the reply. I'm glad to hear that it's that simple. I used the same principle when the verticals were dedicated to 40M and were 1/4wl tall where I fed them with 3/4wl and 5/4wl coaxial runs. The gain and side nulls were impressive. I will invest in some coax and let you know how things develop. Thanks again Carl AG6X -Original Message- From: Richard (Rick) Karlquist [mailto:rich...@karlquist.com] Sent: Sunday, November 29, 2015 11:02 AM To: Carl Braun; topband@contesting.com Subject: Re: Topband: 1/2 wl verticals and spaving On 11/28/2015 6:23 AM, Carl Braun wrote: > Any suggestions or websites available on ½ wl spacing and ½ wl radiators? > > Carl AG6X > I did some modeling of this a long time ago. Basically, the issue is that if you feed the 1/2 wave verticals at the base, you need to have a *voltage* forcing feed, rather than the usual current forcing feed used for 1/4 wave verticals. This is tough to do if you need a 90 degree phase shift as in a 4 square. However, you are in luck because you only need a 0 degree or 180 degree phase shift. As long as your array is physically symmetrical, any symmetrical feed network will give the right phasing. I suggest a simple T junction (in coax) with 1/2 wave lines to the verticals. Make one of them 3/2 wave for 180 degree phasing. The impedance at this point may be too high for an off the shelf transmatch, so you might have to roll your own. Rick N6RK _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Diversity-capable transceivers
Barry and fellow Topbanders I used an Icom 7800 for diversity reception and found it to be a wonderful performer. I would listen to my vertical array on 80 while monitoring the same signals with my second receiver connected to either a Pixel loop or a rotatable 80 dipole. Now I am back to my trusty FT1000D with dual RX but it doesn't compare to the 7800 due to the disadvantaged 2nd RX in the 1000D. The main RX has all filters (incl roofing) but the 2nd RX can only do so much as it introduces noise into the mix degrading any weak signals combined from the main RX. I hear a lot of DXers speaking highly of the Yaesu FTDX5000 series of radios. The Sherwood reports seem to think they are among the best "knobbed" XCVRs out there if you look past the Flex and K3 rig specs. The 5000 , the Icom 78XX series and the 990 all seem to be great for dual diversity however there are some real price differentials in the pack. Carl -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Chortek, Robert L Sent: Monday, November 30, 2015 5:36 AM To: Barry N1EU Cc: topBand List Subject: Re: Topband: Diversity-capable transceivers Hello Barry, I have been using the 990 for over a year and use it daily on the Low Bands. I find it an exceptional performer. The ergonomics are not quite as good as the ICOM 7800, but the receiver performance is much better. The capability of the radio is at its best on the low bands, if you look at the ARRL and Sherwood engineering receiver performance figures. You can set both receivers to track one another, but the second receiver in the 990 is from the Kenwood 590, and is a slightly lower performer, but still very good. I do not use it on diversity. I have absolutely no regrets. 73,Bob AA6VB Sent from my iPhone > On Nov 30, 2015, at 5:24 AM, Barry N1EU <barry.n...@gmail.com> wrote: > > A little research reveals that the TS-990S uses a down-converting > subreceiver on the low bands. Can anybody comment on the stereo > diversity capability and performance of the TS-990S and generally how > it performs on low-band cw? > > Thanks & 73, > Barry N1EU > >> On Mon, Nov 30, 2015 at 6:05 AM, Barry N1EU <barry.n...@gmail.com> wrote: >> >> I'm not familiar with the Yaesu/Icom/Kenwood offerings. Other than >> the K3/K3S and Orion/RX366, do any of the other knobbed (non-SDR) hf >> transceivers offer a down-converting second receiver that can be used >> in stereo diversity mode? >> >> Thanks & 73, >> Barry N1EU >> _ >> Topband Reflector Archives - http://www.contesting.com/_topband > _ > Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: 1/2 wl verticals and spaving
Topbanders Im currently using a two element vertical array that I'm able to use on both 80 and 160M by switching in two different feedlines and matching schemes. The system works well using a Comtek switch box on 80 with the verticals spaced at ¼ wl and the classic Christman method of feeding the verticals on 160 via 157 deg feedlines and 37 deg delay line. Using the same vertical elements results in 1/8 wl spacing on 160. On last challenge I want to tackle is using the same verticals on 40M. The elements would then be effectively spaced ½ wl apart and would be ½ wl tall. I cannot find any patterns or phasing suggestions for this arrangement...only ¼ wl radiators. Can anyone offer any suggestions for feeding an array like this on 40M? In the past I use the same verticals for 40m but they were only 33' tall and I fed it in and out of phase using the Christman coaxial delay line technique and it worked well...however, my elements are now 65' tall and all the math surely changes. Any suggestions or websites available on ½ wl spacing and ½ wl radiators? Thanks Carl AG6X _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Zone 2 on 160m
Steve, For what it's worth, VB2T will be a multi-single from Zone 2 for CQ WW SSB this year. You can see this at http://www.ng3k.com/Misc/cqs2015.html. Haven't seen any Zone 2 plans yet for CQ WW CW. Keep your fingers crossed. Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: HVDC
A 500KV DC line that is part of the major Northeast corridor has been about 3/4 mile from me for 15 years or so and absolutely quiet as are the much older 100 and 250 KV AC lines in the same Northeast corridor which originates in Hydro Quebec and the Seabrook nuke. My noise sources are always the residential 14KV ones or from homes and farm barns. Carl KM1H - Original Message - From: Ws9v w...@royell.net To: topband@contesting.com Sent: Tuesday, February 10, 2015 12:52 PM Subject: Topband: HVDC Hi All Through the center part of Illinois they have begun work at the government level to install a 690,000 VDC power line As with all this there is huge amount of opposition an even groups trying to ban it Does anyone have any experience with a line of such high VDC as a noise source ? It will pass within 3/4 of a mile south of my QTH I am really concerned my only hope if this goes thru is to pull up stakes an move rather than attempt to fight its noise Any thoughts de WS9V Skip _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2015.0.5645 / Virus Database: 4284/9090 - Release Date: 02/10/15 _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: details about the WFAN skywave plot
The E region critical frequency at night is around 0.45 MHz. That says any elevation angle less than about 45 degrees at 660 KHz does not get through the E region. The skywave plot showing the 0.25 mV/m RMS field strength contour line is for a one-hop E mode at a distance of around 1150 km at an elevation angle of about 6 degrees. Shorter distances from WFAN are still an E mode, until ground wave takes over. The question comes down to how far out from the antenna does ground impact an elevation angle of 6 degrees? Al K3LC did a study of this on 160m, 80m and 40m using vertical monopoles, and presented his results in the September/October 2006 issue of NCJ. From his work, we can extrapolate his data (with some caution) - and it looks like ground is important out to about 2.2 wavelengths at 6 degrees elevation, which is just over a half mile on 660 KHz. That puts 'ground' to the east through south out in the Long Island Sound and out in the Atlantic Ocean. So I would expect the skywave plot to be elongated to the east through south at the 0.25 mV/m contour line. It appears that the data was generated using a signal strength prediction program as 50% of the time was used in the qualifying remarks (50% implies a median value - which likely comes from our monthly median model of the ionosphere). But the prediction program didn't look at ground around the antenna. Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Elimination of Treadmill RFI on 160 meters
Nice to hear all the comments, recommendations, and indeed some success stories here. I too have a treadmill problem. Although I'm blessed with a radio-friendly spouse who always asks before she starts it up, I'd like to add a line filter. Ferrites on the cord don't by themselves squelch it. Murphy dictates that the new one will show up when she's in the middle of her workout. How about some outlet box recommendations? The electrics are not the hard part for me, it's the mechanics. I've been looking for a suitable box to mount it all in and coming up kind of dry. Maybe I'm not looking for the right keywords. Seems simple, a box with a cutout for two 120VAC outlets and enough room inside for a line filter and some toroids. A strain relief clamp would be a big plus but something else can always be worked out for that. In the past I've bolted a surface mount outlet box to another project box but it's kinda big and ugly, and more expensive than it ought to be. 73 and thanks in advance, Carl WS7L _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Radial Wire
Good link Frank, thanks. Some here might be interested in some of these. That #12 copperclad could be interesting if the copper is thick enough for 160 transmitting and you can overlook the color! http://www.ebay.com/itm/1000-FT-COPPER-CLAD-STEEL-TRACER-LOCATING-WIRE-12-AWG-30-V-YELLOW-Made-in-USA-/251658885983?pt=LH_DefaultDomain_0hash=item3a9809db5f http://www.ebay.com/itm/500FT-UNDERGROUND-PET-FENCE-WIRE-18AWG-SOLID-GREEN-30-MIL-JACKET-MADE-IN-USA-/251663392372?pt=LH_DefaultDomain_0hash=item3a984e9e74 http://www.ebay.com/itm/500-FT-TFN-TEWN-WIRE-18-AWG-SOLID-600-V-MADE-IN-USA-3-COLORS-AVAILABLE-/251558308312?pt=LH_DefaultDomain_0hash=item3a920b29d8 http://www.ebay.com/itm/500FT-UNDERGROUND-PET-FENCE-WIRE-16AWG-SOLID-ORANGE-30-MIL-JACKET-MADE-IN-USA-/251673136635?pt=LH_DefaultDomain_0hash=item3a98e34dfb Carl KM1H From: donov...@starpower.net To: topband@contesting.com Sent: Wednesday, October 22, 2014 2:17 PM Subject: Re: Topband: Radial Wire iwc2carl on ebay is my favorite supplier of bulk wire. He's very reliable, consistently less expensive (including shipping) than the retail stores and electrical wholesalers, ships in a few days and you can't beat the convenience of delivery direct to your door. He almost always accepts an offer of 90% of his asking price. http://www.ebay.com/sch/iwc2carl/m.html?_nkw=_armrs=1_ipg=_from= For radials I typically use 1000 foot reels of 16 AWG stranded for $50.00 per reel plus ten dollars for shipping. 73 Frank W3LPL - Original Message - From: Jim Brown j...@audiosystemsgroup.com To: topband@contesting.com Sent: Wednesday, October 22, 2014 6:42:03 PM Subject: Topband: Radial Wire On 6/26/2014 2:24 PM, Bill Wichers wrote: You can get solid thhn. Some codes even require it, but it is much less common. I've seen Home Depot stock it before. Solid #12 and #14 THHN on 500 ft spools is stocked by every Home Depot and Lowes store I have visited. They even offer a discount (10% on 5 or 6 spools, I think). I prefer #14 solid because it seems to remain in place a bit better than stranded. I would use #18 if it were widely available at good prices. 73, Jim K9YC _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2015.0.5315 / Virus Database: 4181/8433 - Release Date: 10/22/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: TX relays
So WHAT IS the manufacturers part number of an adequate relay? Carl KM1H - Original Message - From: Tom W8JI w...@w8ji.com To: Tim Shoppa tsho...@gmail.com; Mike Waters mikew...@gmail.com Cc: topband topband@contesting.com Sent: Thursday, October 09, 2014 9:46 AM Subject: Re: Topband: TX relays Because there are many things that go into relay selection that do not show on a data sheet, I always dissect and test relays. I have found 30 amp power relays that overheat at 5 amps at 28 MHz, and relays that have high contact voltage ratings that make the pole inside the coil hot with full RF. They wind up with 20-30 pF capacitance from armature to coil. Another issue is resistance and reliability at near zero contact voltage when receiving. This is probably the single biggest relay issue in our applications. A small bifurcated contact relay is better for receive reliability, and a high current hot switch design is by far the worse for receive reliability. One particularly troublesome high power area for current are the relay internal leads, and the contact support bar materials. The things that make the wires and contact bars last a long time in repeated cycles create very high radio frequency resistances. This is why some large 30 amp power relays will discolor contacts or melt insulation at several amps on higher frequencies. The same thing applies to contacts. Contact materials and platings that optimize hot switching create RF resistance and low level signal connection issues. A gold flash on a soft contact, for example, is excellent for receive but will instantly deteriorate if hot switched at more than a few hundred milliamperes or with an inductive load. It might handle 20 amps of closed contact RF current, but only be rated for a few amps of hot switching current. In contrast, a silver cadmium oxide contact can take tons of hot switch voltage and current, but is lousy for relay receive pass through. Contact support bars, and the wires used in some relays, can also be very problematic. This is because the materials and any weave in wires is designed for flexibility. Alloys and construction that improves mechanical cycle life greatly reduces RF performance. Mike, I would be concerned about using these small relays for non-resonant antenna switching where the impedance at the switch point may be wildly away from 50 ohms. This is the relay I use to switch tuning networks at non-50-ohm points: http://www.deltrol-controls.com/products/relays/power-relays/900 Deltrol is the brand you get if you order from McMaster-Carr but all the big relay manufacturers sell these open frame relays. I also bend the relay contacts for wider spacing as recommended by N6RK in QST (page 66, May 2009 QST Hints and Kinks, Increasing Relay Voltage Handling). Open contact gap of 0.5 inches is readily achievable. Tim N3QE On Thu, Oct 9, 2014 at 6:19 AM, Mike Waters mikew...@gmail.com wrote: This relay looks exactly what I was looking for to remote-switch my 160m inverted-L to other bands, because it will withstand a lot of voltage. From the PDF: High insulation Insulation distance (between coil and contacts): 10mm min. Dielectric strength: 5KV Surge strength: 10KV 73, Mike www.w0btu.com On Thu, Oct 9, 2014 at 2:23 AM, Thomas PA1M t.b.ti...@gmail.com wrote: Fujitsu FTR-K1CK012W _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4765 / Virus Database: 4037/8351 - Release Date: 10/08/14 _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4765 / Virus Database: 4040/8354 - Release Date: 10/09/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: TX relays
So what is the actual manufacturers catalog numberor is that just another DXE secret? Since not everyone has DXE products an easy to source item would be beneficial to the ham community. Carl KM1H - Original Message - From: Tim Duffy k...@k3lr.com To: 'Jorge Diez - CX6VM' cx6vm.jo...@gmail.com; topband@contesting.com Sent: Thursday, October 09, 2014 8:47 AM Subject: Re: Topband: TX relays Hello Jorge, No. Here is the relay in the DXE TFS4. This relay another good choice for TX array building. http://www.dxengineering.com/parts/dxe-rly-hp 73, Tim K3LR -Original Message- From: Jorge Diez - CX6VM [mailto:cx6vm.jo...@gmail.com] Sent: Thursday, October 09, 2014 7:37 AM To: k...@k3lr.com; topband@contesting.com Subject: RE: Topband: TX relays Hi Tim This are the same relay used in the DXE TFS4 4SQ systems? 73, Jorge CX6VM/CW5W -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Milt -- N5IA Sent: Wednesday, October 08, 2014 9:39 PM To: topband@contesting.com Subject: Topband: TX relays What make and model of DPDT relays are you using in your TX arrays? What are your sources? I am looking for some 12 VDC units that are capable of handling full legal limit power to install in a controller for a multi-element directive array. Thanks in advance for any and all suggestions. 73 de Milt, N5IA - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4765 / Virus Database: 4040/8351 - Release Date: 10/08/14 _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband --- Este mensaje no contiene virus ni malware porque la protección de avast! Antivirus está activa. http://www.avast.com _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4765 / Virus Database: 4040/8354 - Release Date: 10/09/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: TX relays
On Thu,10/9/2014 11:18 AM, Tom W8JI wrote: I know you want one-part-number-fits-all answers, but I do not think that is possible. That's your assumption, but certainly not mine. What I think most of us would appreciate are known good products for specific (or define ranges of) applications. Your observations about quality decline with outsourcing is certainly appreciated. Indeed, that is part of the experience we ought to be sharing. 73, Jim K9YC _ Nor mine either. When Tom doesnt want to divulge anything interesting that threatens his secrecy he resorts to insults and a lot of dancing around the subject. Is the RCS-8V any better than the RCS 4, 10 and 12 which all use the rugged DPDT relay used in the Senior Ameritron amps? Board layout has improved for increased isolation and the relays are easily replace if needed. The RCS-8V uses a so called custom relay which costs $33.80 each for replacement while the RCS-4 relay is $6.64 from Ameritron. OTOH there is only a $10 difference between both end products. For HF to 6M the RCS-4 has 3 relays and rated at 2500W continuous average power. The RCS-8V has 5 relays and is supposedly good for 5KW to 30 mHz but only 1 KW at 150 mHz. A full set of replacement relays cost as much as the complete product! Does anybody smell a scam here? Im not grumpy Tom, just frustrated with getting a straight answer out of you instead of hiding behind what ever nonsense verbiage you like to throw out such as: For example, the RCS8V uses a custom tooled relay that has a double make double break contact, or form X contact. It isn't under a part number at Mouser Translation: it is configured as a transfer relay ( the form X contact (it should read configuration)) with each leg in parallel due to a shorting bar between them explained as a long winded elaboration double make double break contact or form X contact . It isn't under a part number at Mouser Maybe not but a regular DPDT relay could be modified at home to be a credible performer thru 6M. There is nothing earth shattering about a transfer relay Tom, they have been around possibly since relays were invented. I use an ancient 4 port Dow Key on my 1500W 2M amp. A Transco transfer relay is used on the 222 mHz 1500W amp and another on the 400W for 432. Most HF amps use a different form of transfer relay which is simply a standard DPDT wired for the required transfer function. No magic there either. Bifurcated contact simply means twin contact, aka parallel. Here is an excellent tutorial on relay terminology http://www.relaymaster.com/Glossary.aspx BTW, some states have passed laws against companies that refuse to release service information to independent shops. Its time you and DXE as well as a few others are included if it doesnt become voluntary. Carl KM1H _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: TX relays
- Original Message - From: Jim Brown j...@audiosystemsgroup.com To: topband@contesting.com Sent: Thursday, October 09, 2014 3:37 PM Subject: Re: Topband: TX relays On Thu,10/9/2014 11:18 AM, Tom W8JI wrote: I know you want one-part-number-fits-all answers, but I do not think that is possible. That's your assumption, but certainly not mine. What I think most of us would appreciate are known good products for specific (or define ranges of) applications. Your observations about quality decline with outsourcing is certainly appreciated. Indeed, that is part of the experience we ought to be sharing. 73, Jim K9YC On Thu,10/9/2014 11:18 AM, Tom W8JI wrote: I know you want one-part-number-fits-all answers, but I do not think that is possible. That's your assumption, but certainly not mine. What I think most of us would appreciate are known good products for specific (or define ranges of) applications. Your observations about quality decline with outsourcing is certainly appreciated. Indeed, that is part of the experience we ought to be sharing. 73, Jim K9YC _ Nor mine either. When Tom doesnt want to divulge anything interesting he resorts to insults and a lot of dancing around the subject. Is the RCS-8V any better than the RCS 4, 10 and 12 which all use the rugged DPDT relay used in the Senior Ameritron amps. Board layout has improved for increased isolation and the relays are easily replace if needed. The RCS-8V uses a so called custom relay which costs $33.80 each for replacement while the RCS-4 relay is $6.64. OTOH there is only a $10 difference between both end products. For HF to 6M the RCS-4 has 3 relays and rated at 2500W continuous average power. The RCS-8V has 5 relays and is supposedly good for 5KW to 30 mHz but only 1 KW at 150 mHz. A full set of replacement relays cost as much as the complete product! Does anybody smell a scam here? Im not grumpy Tom, just frustrated with getting a straight answer out of you instead of hiding behind what ever nonsense verbiage you like to throw out such as: For example, the RCS8V uses a custom tooled relay that has a double make double break contact, or form X contact. It isn't under a part number at Mouser Translation: it is configured as a transfer relay ( the form X contact (it should read configuration)) with each leg in parallel due to a shorting bar between them explained as a long winded elaboration double make double break contact or form X contact . It isn't under a part number at Mouser. There is nothing earth shattering about a transfer relay Tom, they have been around possibly since relays were invented. I use an ancient 4 port Dow Key on my 1500W 2M amp. A Transco transfer relay is used on the 222 mHz 1500W amp and another on the 400W for 432. I use a transfer switch on my house generator. Most HF amps use a different form of transfer relay which is simply a standard DPDT wired for the transfer function. No magic there either. The RCS-8V relay can be duplicated at home from a standard DPDT with decent performance to 6M Bifurcated contact simply means twin contact, aka parallel. Here is an excellent tutorial on relay terminology http://www.relaymaster.com/Glossary.aspx BTW, some states have passed laws against companies that refuse to release service information to independent shops. Its time you and DXE as well as a few others are included if it doesnt become voluntary. Carl KM1H _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Help put Haiti on topband
Thanks to all for the comments. I will pass them along to Dale, who is not on the reflector at this time. (I need HH on 160 too!) 73, Carl WS7L _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: 160 ground plane choke
I would think the W2DU style would be the lightest but also pretty ineffective on 160 as well as power limited. Use a heavier duty rope (or #12 solid Copperweld , non resonant lengths of course for all bands), and a couple of Fair-Rite 2631803802 31 mix 2.4 toroids. Use RG-400, to wrap the toroids and then LMR-400 or similar if running 1500W. RG-8X will handle 1500W on 160 but its a bit marginal especially when the VSWR climbs or when you decide to try digital or RTTY. Carl KM1H - Original Message - From: Cqtestk4xs--- via Topband topband@contesting.com To: topband@contesting.com Sent: Saturday, September 27, 2014 9:50 AM Subject: Topband: 160 ground plane choke I've been using a 160 GP with 4 radials. It's a Tee-top supported with a rope between two towers, with the top around 165 feet and the base at 70 feet. I'm feeding it with RG8X to keep the weight down on the rope which supports it. Although it works well I would like to negate any loading which might be taking place on the feed line which drops from straight down from the base. Any ideas for a cheap, easily made, effective choke on the feedline? Bill K4XS/KH7XS _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4765 / Virus Database: 4025/8283 - Release Date: 09/27/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Beverage Question
The way I understand is that you will be using the WD-1A as individual lines with each having its wires connected in parallel. Id start by calculating the resultant wire gauge such as say two #24 in parallel = a #21; I dont know what the fudge factor would be due to wire and jacket insulations in determinining the 6 spaced line impedance. From what Ive read that is too much spacing for best performance due to imbalancing plus not being a bit twisted to cancel the imbalance as with ladderline and conventional WD-1A useage. If the reason for change is poor strength and reliability then why not go with parallel galvanized or aluminum fence wire and create some twisting arrangement every 100' so. In the more conventional installation I calculated about 93 Ohms for the WD-1A and use a 1:1 ratio for 75 Ohm coax; cant notice any deterioation between that and using 50 Ohm coax with its own transformer. Both work fine to 30M. Carl KM1H I want to replace the 450 ohm ladder line for my two DXE 720 ft long bi-directional beverages with two lengths of WD-1/TT field telephone wire. The wires will be secured only at the ends, but will be suported along their length by ceramic insulators mounted on 4x4 posts spaced every 60 ft. The spacing between the parallel wires will be about six inches. Here are my quesetions: First, does anybody know what the likely impedance is of this configuration, or if not, how to measure it? Second, if I keep the DxE matching trnsformers used with the 450 ohm ladder line, will beverage performance be degraded noticeably with the new wures if, say, the impedance of the new line turns out to be 600 ohms or so? In other words, as a practical matter how important to performance (e.g., F/B ratio and low-noise) is it to make sure impedances are matched. Finally, a mechanical question. I want to have a pulley at one end of the parallel wires to equalize the tension in the wires. I've not been able to find a good pulley with a five or six inch diameter, except for nylon pulleys used for clotheslines. Do you think one of these could be used. There will be no motion of the pulley, since it is only used to equalize tension. The field telephone wire is rated at 200 lbs maximum tension, and I'm guessing the actual tension will be about half that. Thanks! Jim W8ZR _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4765 / Virus Database: 4025/8246 - Release Date: 09/20/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: [Bulk] Re: Outdoor rope suggestions
As I stated when I started this thread about 2 weeks ago Ive had STI line in use since 1983 for all sorts of outdoor projects including boom supports. I was looking for alternatives and went with Davis Dacron because they carried 1000' spools; being in the same state cut down on shipping and gave next day service. The two brands look identical. The longest runs these days is to support seperate 160, 80, and 75M inverted v's with a common coax feed at 180' with the ends out to 300' or so from the tower base. Several pieces are knotted together and takes all that Mother Nature can toss at if from ice storms to hurricanes, microbursts, N'oreasters, etc. Carl KM1H - Original Message - From: Grant Saviers gran...@pacbell.net To: topband topband@contesting.com Sent: Wednesday, September 17, 2014 5:54 PM Subject: Re: Topband: [Bulk] Re: Outdoor rope suggestions I've had real Synthetic Textiles lines up 10 years and more. Some in CA sun, without significant degradation. OTOH, some dacron bought on ebay is likely a dacron-polypro blend and lasted only a few years. Grant KZ1W On 9/17/2014 2:37 PM, Tom W8JI wrote: In about 7 years that Dacron stuff starts to dry out and comes apart slowly, Rots it in water like rain gutters. Perhaps you are confusing it with something else, or you bought some fake Chinese forgery? Dacron rope (a trade name for a polyester rope derivative with less stretch than nylon) is rated everywhere as being excellent for UV resistance with good or excellent chemical resistance, mildew resistant, and good abrasion resistance. It is commonly used as a marine rope. I have some that has been up for 15 years in Georgia sunshine, and it was used when I installed it! There are some inferior ropes out there. I bought some Wal-Mart Nylon rope that had no UV resistance at all. It lasted less than a year, while other Nylons last many years. The Wal-Mart made in China Nylon rope was more like polypropylene. _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4765 / Virus Database: 4015/8230 - Release Date: 09/17/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: WTB: Guy wire stuff
Thanks for that nice report Wayne. Those are the same Grips Im using here. I dont know about these days but when I was installing the 4 towers here I was informed that Rohn EHS was made in Korea as was just about all the utility and CATV strand. Rohn just added a premium cost to it. When this town was cabled I got literally miles of left over 1/4 EHS and hardline from 1/2 to 7/8 for a couple of cases of beer. I used my 2 axle race car trailer to move it. The installers had already been paid and dont transport but very little extra and besides their next job was in OHreal gypsies and higher than a kite most of the time. Carl KM1H - Original Message - From: Wayne Kline To: Carl ; JI Charles ; low bad reflector Sent: Friday, September 05, 2014 1:16 PM Subject: RE: Topband: WTB: Guy wire stuff Just my .02 Some call them Tomatoes some call them Tomottos but even those fruits come in different size and texture . When I built my station @ this QTH 4 guyed towers with broken up guys 502 insulators and a PRE Formed guy Fasteners . A fellow FRC member had a source for 5000' rolls of 1/4 Strand and 502 insulators and these GUY grips that are used in the Cable industry... from pole to pole to support the cable. These grips had the 4 twisted wire with yellow tag I had access to the Quality Control Lab @ the Mack Trucks test lab, We first tested Rohn 1/4 EHS. to facilitate the pull I installed 3 Press furls on each end all test were repeated 2X The EHS began to stretch twist and fracture @ 9K and fail @ 10.2K lb pull Rohn PLP BIG GRIP (5) strand , with a length of 1/4 EHS and the same furl at the end never failed with the EHS stretching and failing at 11 + K lb pull now the Shorter 4 strand twist yellow tagged with the same length EHS ( 16 exposed if my memory serves me ) This to never Failed and the 1/4 EHS both times failing . We painted layout dye on the 1/4 ehs/grip ends looking for pull out NONE was found on either DEAD END the guy grip loop end was around a solid 1 .250 rod to mimic a 502 or Rohn tower leg or HD thimble. I tried Thimbles but the press destroyed them in the clamp down securing phase . Conclusion 4 towers 180 plus guy grips All 4 strand DEAD End type and 25 years and all A - OK... I even caught a lower level guy on my ROPS bolt on my BIG tractor pulling so hard till I got to stop it Ripped the joint open and bent it 70 degree on ROHN 25 AND DID NOT FAIL. It's length was 73' with two 502's attached directly to the tower leg and three way equalizer plate. MY .02 From: k...@jeremy.mv.com To: w...@w8ji.com; topband@contesting.com Date: Fri, 5 Sep 2014 10:46:37 -0400 Subject: Re: Topband: WTB: Guy wire stuff Preform comes from the name of a major grip manufacturer, not from tower apes. http://www.preformed.com/ ** Which has never been denied by anyone in this discussion. OTOH linemen and other strand installers use it as a general description thus my tower ape terminology. Dead end is the termination style of grip. http://www.preformed.com/index.php?option=com_phocadownloadview=categoryid=15Itemid=145 ** Also previously discussed The normal Guy Grip dead end is typically used on any shorter length guy line that does not have rotational or twisting forces, and they are normally are rated at 100% of stand breaking strength (but you should check the catalog specs because some are less). ** As are the Big Grips rated at strand strength. The Big Grip dead end is the Prefomed Line Products name for the longer grips, and are better for longer guy runs that might twist. PLP manufactures custom grips that are not cataloged. PLP would probably be a better place for application advice than Ham tower parts vendors (who sell some pretty sketchy stuff at times) or Ham reflectors. :) ** PLP marketing is aimed at commercial and industrial applications and not hobbiests. Their idea of a radio tower starts where most ham versions let off. Every tower failure I have seen has come from incorrectly installed guy strand, saddle clamps, or anchors. I've seen towers where people splice guy lines with dead ends looped through dead ends! ** Ive even seen some with RatShak guy wire which is maybe 1/8. Ive never used an inline splice either. It's common to see someone worry enough to buy extra long grips (which doesn't do much for strength), and then not worry about radius inside the loop (which just kills the strength). ** Good points Carl KM1H
Topband: Big tower
So who will be the first to build this for that 160M 3 el yagi and maybe a 5 el for 80 at some lower height? There has to be a few with that much money and huge ego. http://mortenson.wistia.com/medias/tejnwpitig Carl _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: WTB: Guy wire stuff - please be safe
Sounds like a lot of Nervous Nellie knee knocking to me Tim. Caution within reason is a good thing, understanding that all Rohn tower specs plus PLP and other hardware providers are extremely conservative has to be considered also. Going overboard with disaster predictions does nobody any good. First of all Im only going to 90' of 25G where 3/16 is the Rohn spec and Im going to 1/4. The tower will be lightly loaded, by my standards, and even grips that are 2 shorter will have far more holding power than the tower calls for. All my towers use Rohn guy brackets with torque arms, none of the Hammy Hambone method of wrapping the guy around a tower leg. The difference between properly tensioned 3/16 and 1/4 guys on 25 and 45G is immediately felt as the tower is much more stable feeling with the latter; especially when muscling around heavy stuff at the top and/or with 2 people. My 180' 45G has been up since 1990 and the Rohn spec is still for 3/16. Im using 1/4 with the guy anchors at the full Rohn spec distance. For added safety I used the proper size guy clamp near the end of each grip as recommended by a REAL tower professional who I used to assist on 300-600' work. The tower also sits on a pier pin so the guys do all the work. As you and many others know Im on top of the highest hill in 20+ miles and subject to intense hill effect updraft winds plus numerous nor'easters, micobursts, high speed T storms, Cat 1-2 hurricanes plus general unamed coastal storms with hurricane class gusts. The ocean is 20-30 miles from here over a wide azimuth and it is all downhill from here. Im also known for exceeding Rohn loading specs as far back as the 60's. For several years here the 180' had a 4/4 KLM 4el 40 plus 4/4/4/4 PV-4's (40' booms) on 20. The only damage was keeping the top KLM from breaking element to boom insulators. The pier pin and oversized 1/4 guys did exactly what I intended. The 100' 25G was also overloaded with 10 and 15M stacks plus 2M and 222MHz pairs of long booms. Those two towers also have 22' chrome moly masts. The above is Real World Testimonial. Carl KM1H Be very careful with real world testimonials - giving advice to use products for the wrong application is really dangerous. We are talking about serious tower projects that can turn fatal if you use the wrong equipment. I don't care how high the tower is. PLEASE USE THE RIGHT STUFF! If anyone uses the wrong tower hardware and does not have problems or does not get killed, I call that luck. Do you want to bet your life on luck? Use the EXACT product that is specifically designed for tower applications. Do not take short cuts! Pay attention to the tower, guy wire and antenna manufactures instructions. Tower guy wires are special. Talk to a professional mechanical engineer with tower engineering experience, he will tell you. There is a reason there are two different PLP products for two very different applications. Every year several Hams are killed in tower accidents because they took short cuts, bad chances or tried to save money - or worst of all, they got bad advice. What is your life or one of your friend's lives worth? Have you ever gone to a funeral of a tower climber? I have - and it changed my life forever. PLEASE BE SAFE 73, Tim K3LR -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Cecil Sent: Thursday, September 04, 2014 10:44 PM To: donov...@starpower.net Cc: Carl; topband@contesting.com Subject: Re: Topband: WTB: Guy wire stuff Have been for the last 7 years...no issues at all. The tower products are just an adaptation of products used in the power distribution business for years. I work for an electric utility, one of the largest in the US. I've seen both products and see no difference in their design. The preformed line products grips are used to guy transmission towers on a routine basis. We also use them to support fiber optic cables on distribution and transmission structures. I chose the PLP grips for my 65' tower...they were a good bit cheaper. I also used screw down anchors for my guy points...the ones used in the electrical distribution business. Bigger plates, galvanized instead of painted and heavier dutyfor less money. But it is a personal choice Cecil K5DL Sent from my iPad On Sep 4, 2014, at 3:13 PM, donov...@starpower.net wrote: Hi Carl, Preformed Line Products says: Guy-Grip Dead-ends are intended for use on single wood poles associated with distribution construction. If you examine the Rohn tower hardware catalog, they list only Big Grips, never a mention of using wood pole Guy Grips on any of their towers For a few dollars more you can use the BG-2144 Big Grip product recommended by the manufacturer for use on towers. Use Guy Grips for wood poles at your own risk... 73 Frank W3LPL - Original Message - From: Carl k...@jeremy.mv.com To: donov...@starpower.net, Bill Wichers bi
Re: Topband: WTB: Guy wire stuff
Preform comes from the name of a major grip manufacturer, not from tower apes. http://www.preformed.com/ ** Which has never been denied by anyone in this discussion. OTOH linemen and other strand installers use it as a general description thus my tower ape terminology. Dead end is the termination style of grip. http://www.preformed.com/index.php?option=com_phocadownloadview=categoryid=15Itemid=145 ** Also previously discussed The normal Guy Grip dead end is typically used on any shorter length guy line that does not have rotational or twisting forces, and they are normally are rated at 100% of stand breaking strength (but you should check the catalog specs because some are less). ** As are the Big Grips rated at strand strength. The Big Grip dead end is the Prefomed Line Products name for the longer grips, and are better for longer guy runs that might twist. PLP manufactures custom grips that are not cataloged. PLP would probably be a better place for application advice than Ham tower parts vendors (who sell some pretty sketchy stuff at times) or Ham reflectors. :) ** PLP marketing is aimed at commercial and industrial applications and not hobbiests. Their idea of a radio tower starts where most ham versions let off. Every tower failure I have seen has come from incorrectly installed guy strand, saddle clamps, or anchors. I've seen towers where people splice guy lines with dead ends looped through dead ends! ** Ive even seen some with RatShak guy wire which is maybe 1/8. Ive never used an inline splice either. It's common to see someone worry enough to buy extra long grips (which doesn't do much for strength), and then not worry about radius inside the loop (which just kills the strength). ** Good points Carl KM1H _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4765 / Virus Database: 4015/8155 - Release Date: 09/04/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Outdoor rope suggestions
Thanks to all for the suggestions. Ive been using the Synthetic Textiles since the 80's when it first came to my attention in a YCCC newsletter and have been very pleased with it. Price from DXE is $140 for two 500' reels and free shipping. OTOH I decided Id rather have a 1000' reel and eliminate extra knots and went with Davis RF and a 1000' spool of 3/16 Dacron at $130 and $15 shipping (they are in NH). Specs appear to be the same or close enough for my needs. Now to chase down some reliable pulleys as Im not about to climb 180', or trees at the other end more than once. As far as the antenna wire it will likely be #10 or 12 solid deep well motor wire as I have a lot of it salvaged for the asking back when copper was still cheap. It has a heavy jacket which will reduce the physical length. What it will do with UV and acid rain will be TBD but the lower end of the catenary ropes will have sufficient length to bring it right down to vertical for service. I might run two different lengths so as to give a flatter VSWR up to 2MHz since I do use AM on 160 at times. Also TBD. Carl KM1H _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: WTB: Guy wire stuff
Ive been spending a lot of time trimming and removing trees around my shorty 60' tower which was the first one up when I moved here in 89. It is amazing how fast they seemed to overtake my space in just 25 years!! Since it is also time to replace the decidedly rusty 3/16 cable Ive decided to extend to 90' as well as use 1/4 guys as on the other 3 towers. This will allow me to do a lot more with the aluminum pile out back such as 3/3 on 20 and 8/8 on 6M. What I need is: Up to 12 502 guy insulators Up to 18 1/4 deadends/guy grips Individually prices from dealers is ridiculous and I dont need case loads as I bought when building the other 3 towers in 90-91 and wound up giving away what I didnt use. Any help appreciated. Carl KM1H _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: WTB: Guy wire stuff
Not according to the folks that invented them Frank. The Big Grip is a Guy Grip for serious towers. http://www.preformed.com/index.php%3Foption%3Dcom_phocadownload%26view%3Dcategory%26download%3D44:plp-commcatsec20-2012%26id%3D15:strand-and-cable-products%26Itemid%3D145rct=jfrm=1q=esrc=ssa=Uei=nqoIVJWDDcmayAT5hoHQDAved=0CBQQFjAAsig2=1aPQDpfnvYFm8XWlxXxgjwusg=AFQjCNEns72sjImeKDRibuLmm62WL9bSqA The Preform name is often used as a noun by cable apes (-; Carl KM1H - Original Message - From: donov...@starpower.net To: Bill Wichers bi...@waveform.net Cc: Carl k...@jeremy.mv.com; topband@contesting.com Sent: Thursday, September 04, 2014 1:40 PM Subject: Re: Topband: WTB: Guy wire stuff Tower guys should use Big Grips, not the performs used by electric utilities. You can purchase Big Grips from Texas Towers and many other suppliers 73 Frank W3LPL - Original Message - From: Bill Wichers lt;bi...@waveform.netgt; To: Carl lt;k...@jeremy.mv.comgt;, topband@contesting.com Sent: Thu, 04 Sep 2014 13:31:07 -0400 (EDT) Subject: Re: Topband: WTB: Guy wire stuff If you only need a few like this, try calling some of the utility contractors in your area. They will always have the dead ends and the guys that also do the power work will also have the insulators. They will probably be able to sell you a few without too much trouble. BTW, the utility guys will usually call the dead ends preforms (different industry, different terminology :-), but they are the same thing. The telco/cable guys use 1/4 EHS strand for a support line for their cables so they will always have hardware for that. The preforms are cheap enough from the crew's perspective that they are occasionally used as temporary twist ties to hole up cable prior to lashing. You can order the stuff from Graybar too (probably the telecom division, but the power division can get stuff too), but I don't know about their prices. I've only ever ordered by the carton at work. -Bill gt; What I need is: gt; gt; Up to 12 502 guy insulators gt; Up to 18 1/4 deadends/guy grips gt; gt; Individually prices from dealers is ridiculous and I dont need case loads as I gt; bought when building the other 3 towers in 90-91 and wound up giving away gt; what I didnt use. gt; gt; Any help appreciated. gt; gt; Carl gt; KM1H gt; gt; _ gt; Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4765 / Virus Database: 4015/8153 - Release Date: 09/04/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: Outdoor rope suggestions
Im going to be needing 500-1000' spools of polyester double braid rope for supporting some more wire antennas in the harsh enviroment up here. The 5/16 is rated at 3400 tensile and the wire will be about 50#. ID likely tension it to about 200-250# to reduce sag Or would real Mil-C-5040H type III (550# ) or type IV (750#) paracord be OK? Its certainly not as strong plus it stretches. That spec was inactivated in 1997 and Ive been unable to find its replacement. I only want to do this once as I aint gettin' no younger! Carl KM1H _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Shunt feeding tower
Which is the same height as the one I had in the 80's at another home. With stacked 10-15-20 W2PV-4's it resonated somewhere around 1530 KHz if I remember and an Omega was the only thing that worked well. The gamma rod was 3/4 CATV hardline running thru PVC plumbing T's and pipe then tied of to the tower. Spacing was 24 and the sweet spot to connect was 60' up. Once I found out how poorly 60 mostly 120-130' on ground radials worked I added 4 spokes of 4' x 50' rabbit cage wire mesh from the base and it was an all new antenna that really kicked butt. The soil there was glacial sand better used for mixing concrete! That tower helped win a 160M contest on the second try, going from 600 to 1200W might have helped a bit (-; Pretty soon others started using mesh as I was talking it up often on 160 SSB after the DX faded out on CW. Carl KM1H - Original Message - From: Pete Smith N4ZR n...@contesting.com To: topband@contesting.com Sent: Wednesday, August 27, 2014 6:28 AM Subject: Re: Topband: Shunt feeding tower Reading about 3-wire cages and the like, I feel a serious case of shunt envy. Mine is a single wire about 18 inches from one corner of my Rohn 25, connected to the tower at about 50 feet. I used an omega match with a couple of 3 KV transmitting variables, because my tower is quite tall for 160 (97 feet with 3 yagis, 2 on top) and I could not find a 50-ohm point.It was absurdly easy to adjust and seems to work quite well at 100 watts. I'm sure there are better solutions (including Herb's), but this was really simple. 73, Pete N4ZR Check out the Reverse Beacon Network at http://reversebeacon.net, blog at reversebeacon.blogspot.com. For spots, please go to your favorite ARC V6 or VE7CC DX cluster node. On 8/26/2014 5:12 PM, Don wrote: I would like to get on 160 this question most likely has been asked a 1000 time but I need information as how or can I shunt feed my 55 ft rohn 45 . Don _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4716 / Virus Database: 4007/8110 - Release Date: 08/27/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Shunt feeding tower
All I had on my tower were the 3 coax cables and rotator wire which were all taped to the tower about every 5' which apparently decoupled them. The coax also had about 15 of large 43 mix ferrite beads over them right at the feedpoint a few years before I was on 160. That was for TVI prevention. Carl KM1H - Original Message - From: LB3RE LJ3RE Stein-Roar Brobakken p...@lb3re.com To: Pete Smith N4ZR n...@contesting.com Cc: topband@contesting.com Sent: Wednesday, August 27, 2014 8:35 AM Subject: Re: Topband: Shunt feeding tower How is inteference on rotor or relay boxes?I thinking 1kw generate magnetic radiation into cables ??? How u solve this guys ?? Tnx ---Sent by iphoneLB3RE LJ3RE K3RAG ex: LA6FJAwww.lb3re.com ~ Rag ~ Stein Roar Brobakken e-mail:post@lb3re.comhttp://la5o.wordpress.comwww.contesting.no Reading about 3-wire cages and the like, I feel a serious case of shunt envy. Mine is a single wire about 18 inches from one corner of my Rohn 25, connected to the tower at about 50 feet. I used an omega match with a couple of 3 KV transmitting variables, because my tower is quite tall for 160 (97 feet with 3 yagis, 2 on top) and I could not find a 50-ohm point.It was absurdly easy to adjust and seems to work quite well at 100 watts. I'm sure there are better solutions (including Herb's), but this was really simple. 73, Pete N4ZR Check out the Reverse Beacon Network at http://reversebeacon.net, blog at reversebeacon.blogspot.com. For spots, please go to your favorite ARC V6 or VE7CC DX cluster node. On 8/26/2014 5:12 PM, Don wrote: I would like to get on 160 this question most likely has been asked a 1000 time but I need information as how or can I shunt feed my 55 ft rohn 45 . Don _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4716 / Virus Database: 4007/8110 - Release Date: 08/27/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Shunt feeding tower
The first info needed is are the guy wires insulated from the tower and what is on top including mast? Carl KM1H - Original Message - From: Don w4...@truvista.net To: topband@contesting.com Sent: Tuesday, August 26, 2014 5:12 PM Subject: Topband: Shunt feeding tower I would like to get on 160 this question most likely has been asked a 1000 time but I need information as how or can I shunt feed my 55 ft rohn 45 . Don _ Topband Reflector Archives - http://www.contesting.com/_topband - No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4716 / Virus Database: 4007/8106 - Release Date: 08/26/14 _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: losses on 160m
Rik van Riel asked: One big question is, where does the path loss on top band come from? Per our current understanding of the lower ionosphere, the loss due to absorption on 160m in the lower ionosphere at night is around 10 dB per hop. Added to that is the loss due to multiple ground reflections. If we assume 1 kW and 0 dBi antennas, multi-hop appears to be able to go to about 10,000 km before it's below a quiet noise level. This is why ducting is invoked for extremely long-distance QSOs - less transits through the absorbing region and fewer ground reflections. There's a natural electron density valley in the nighttime ionosphere right above the nighttime E region peak that provides the ducting mechanism - this is the boundary between the top of the E region and the lower F region. Ducting on 160m can be seen when doing ray traces through the nighttime ionosphere. Carl K9LA _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Skimmer calibration
- Original Message - From: Tom W8JI w...@w8ji.com To: topband topband@contesting.com Sent: Tuesday, August 19, 2014 10:08 PM Subject: Re: Topband: Skimmer calibration BC antennas have the elaborate radial system in order to get that groundwave while the typical on ground ham vertical loses a lot of the 0-10 degree (or more) radiation. Go to the beach to get it back.or go with elevated radials. That just isn't factual at all. Radials under the vertical antenna have virtually no effect on wave angle unless they are sparse and grossly unbalanced, allowing them to radiate like a low horizontal antenna. Radials change the efficiency, not the pattern, unless the radials radiate like a dipole. 73 Tom Note that I didnt say anything about changing the pattern, just the energy included at low angles and where the efficiency starts at the base and at the often poorly understood Fresnel Zone if you really want more power in those low angles and not heating worms or sand granules. Carl KM1H _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Skimmer calibration
I said: That just isn't factual at all. Radials under the vertical antenna have virtually no effect on wave angle unless they are sparse and grossly unbalanced, allowing them to radiate like a low horizontal antenna. Radials change the efficiency, not the pattern, unless the radials radiate like a dipole. 73 Tom Note that I didnt say anything about changing the pattern, just the energy included at low angles and where the efficiency starts at the base and at the often poorly understood Fresnel Zone if you really want more power in those low angles and not heating worms or sand granules. That, by definition, is a pattern change. You said it improves groundwave. What you think happen just does not happen. It improves efficiency. It does not change elevation pattern, it does not change Fresnel zone losses significantly. It does not improve groundwave any significant amount more than it changes sky wave. This is because the often poorly understood Fresnel zone extends far beyond practical radial field area, and virtually all of the ground wave attenuation from soil losses is miles from the antenna over the entire long length of a path. It is not localized loss. 73 Tom All of which is well known and well published. You might ask Frank, W3LPL, or Richard Fry to explain it to you better than I seem to do since you appear to get hung up on the semantics. Looking at the coastal AM BCB patterns I mentioned a week (WGBB 1240) ago or others recently will show you the effects of salt water and land. Carl KM1H _ Topband Reflector Archives - http://www.contesting.com/_topband
