Re: Topband: Inverted L improvement question - Part 2
I could give other advice but the best that I could offer is to check out Rudy's, N6LF, site: https://www.antennasbyn6lf.com/ Regrettably, this isn't all that he's published so further searching might be in order. QEX published a series in 2009-2010 of his stuff. In my "Antennas" document folder on my hard drive I have a "Severns" subfolder with practically everything he's written saved. This is a gold mine, only the gold is free. In particular for your needs see LF-MF antenna notes. Wes N7WS On 12/28/2018 4:35 PM, Todd Goins wrote: Thanks for reading and any advise you can give. 73, Todd - NR7RR _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Inverted L improvement question - Part 2
Hi Guy Disclaimer noted. That hoarding gene is much more common than most people think I had an SB101, SB-200. the SB101 is gone but the SB 200 and 2 Drake R4C's and T4Xc's are Still in residence. My mp 1000 was indeed used at high power multi ops. Mine was one of the 5 We used at every cq ww cw and SSB and Arrl CW and SSB contest up at W3PP from 1995 until Dallas perished in that plane crash when taking off from Charleston S C. I was supposed to be on that plane which crashed leaving Charleston SC for Florida and out to C6. After weeks of planning I had to cancel out the day before the flight. I bought my MP-1000 new after using the MP's at W3PP it has the clix mod in it courtesy of W3PP who spent a full day putting the mod In all of 4 of his. It has just come back after being gone over by Byron wa4geg, I didn't know to have him check the choke but he did install the new solid state freq readout and a new CAT board. It has every filter that will fit In it including the w2jvn roofing filter. I Have Known howie NY4A from when he was K4PQL and when his BIG antenna was a TA-33 in a tree and all he had was wires through the woods. It sure wasnt his qth in Lorton va that gave him a good signal as he was basically located in a gulch. We used to ride together to the PVRC meetings at the red Cross building in Arlington Va. he was one of our main ops when I ran the operation at K4CG along with Dallas K3WUW who later picked up W3PP. Dallas and I both worked for Vic Clark W4KFC. When I lived in Dale city, Howie was the one who climbed the trees in my back yard to put up My 80 m dipole and 160m inverted vee. I climbed my own tower as well as towers at W3PP but trees..not so much. As for K3-s I operated 2 dx contests at NR4M. I'm not a big 80M op and I planned to operate 10 or 15M because you almost need to go to a 1 week school To learn BIP, BOP and which antenna to use at what time of day with those 20 m stacks. As it turns out the 80M op didn't show up so they asked if I Would fill the chair until the 80m op came in. What a sweet setup. this was 4 or 5 years back but my first time with actual"hands on" a k3. Actually, there were 2 of them on 80M And the antennas were if I remember correctly a 5 or 6 element delta loop fixed on EU and a 4 square. Diversity was turned on and I had 3501 from the start Of the contest until my eyes slammed shut around 0600 local the next morning as the 80m op never showed up. I have never heard anything like it, it was more akin to 20 meters. Big runs and EU was loud. My only issue with the K3's was what I considered to be the small knobs. I prefer big knobs on women and radios. I attributed The high performance on 80 to be the antennas not the radios. Who knew?? I was so beat after 12 or 13 hours on 80 that I slept until about 3 In the afternoon. I thought I might get on 160M the second night at NR4M but W4DR and w4PRO were there. Compared to them I cant even spell "160", I just watched how the pro's do it. I never did get On 15 or 20. Visitor accommodations at NR4M with a pool table and a quiet place to sleep were like a 5 star hotel compared to the Spartan conditions in the bunkroom at W3PP.As dallas would say, I hope you didn't come all this way to sleep. the diversity in the K3's was amazing. I never gave any thought to the 1000 MP until you mentioned the issues noted below. I will probably never look at my MP-1000 the same again. As you may know "CHAMPIONS ADJUST". I realize that there are now other radios that are better than the MP-1000and I have been very interested in K3ZO's reports on the Yaesu 5000, even though Fred doesn't need filters, I do. I think there is at least One yaesu 5000 at W3LPL I would definitely want 250 and 500 cycle filters on any radio I purchase. I Have not done any multi op since NR4M except for SS CW when my brother NW9X comes up here for SS. I was thinking my 160m issues were antenna related but now that's in question. I will definitely try to bring my MP-1000 to a location with known good Antennas and a K3. It's still true that no matter how much power you have, if you can't hear em, you can't work em. I read all your posts and recently discussed your FCP with Lar K7SV who recently built one. Thanks Guy I appreciate you taking the time to bring me up to date. 73 Chet N4FX -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Guy Olinger K2AV Sent: Sunday, December 30, 2018 11:32 PM To: chet moore Cc: TopBand List Subject: Re: Topband: Inverted L improvement question - Part 2 Hi Chet, Before we start, a disclaimer: I still have my MP, maybe I'm a radio hoarder. I do have a 75A3 and a Johnson Ranger and Courier and an FT 101ZD. The only long used radios I don't still have are my SB300 and SB400, and I wish I hadn't sold those. So my MP bashing is technical and proven, and I still love my MP enough to keep it. I hope its feeli
Re: Topband: Inverted L improvement question - Part 2
Thanks again everyone. I've read all your suggestions and advise and although I won't be able to make some of the more difficult (or impossible at my site) changes there are a few things I'm willing to try. I read the w0btu.com webpage and I'm not really that far off from that setup. Minus that tuning network. I'll order some FT240-31 ferrites to make the feedline choke. Looks easy enough. I have my elevated radials (135' long) at about 10' above ground now, like the website describes. The feedpoint is a little bit higher than that. The website does not say (or I didn't see it) how high the feedpoint should be. Is 10'-12' okay? I can easily move that higher and then the radials would slope downward from the connection point. Also, my total wire length is not 155', it is more like 135'. I'll add 20' of length while waiting for the ferrites to arrive. If this makes a huge difference I'll be shocked and pleased. It works so poorly now compared to the 43' version that except for my desire not to have this thing beat me it really doesn't seem worth the effort. Last night I was easily coast to coast from Seattle. East coast stations on PSK reporter were hearing me well. I was heard in the Faulklands and in JA with the 43' antenna. With the 100' version I was barely making it to Colorado! I'm looking closely at a couple of BCB filters to help clean up my receive situation too. I'd like to be able to use my antenna analyzer to get some usable data. I'm just frustrated that this thing stinks so badly and the 43' model that I frankly threw together in about a day just for the ARRL 160 CW contest has worked 45 states and some DX in almost no time but the 100' has worked essentially nothing at all. It looks more impressive though. Ugh! I will keep providing updates and listen to any advise provided. Until I wad the thing up into a ball... 73, Todd - NR7RR _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Inverted L improvement question - Part 2
d both of them with 100 watts. I called N6RK on both antennas. On the inverted L I got an imi, and on the shunt fed tower no response. Lots of qrm. n6rk was not loud but he was the ONLY w6 I heard. N2IC was loud from new mexico all night. When I try to call cq I can hear partial calls and I know there are stations calling me. I know I was called by an EU4, 9A2 and a TF2 last night but I couldn't pull any of them thru. The shunt fed tower seems to radiate pretty well on xmit but on rx its an alligator. I definitely get out better than I hear but its still pretty discouraging to call CQ and to look at dx summit and see.spots like these from the europeans N4FX ?. N4FX no receiver N4fx don't waste your time calling, rx broken N4FX No ears N4FX Unmanned beacon station?? N4FX Big signal does not hear N4fx code reader failure??? N4FX op asleep at key??? N4fx where is he listening?? is he even listening? N4FX working crossband??? I have tried a 200 foot BOG which actually runs across the street and cars drive over it. (I roll it out after dark but not a busy street). And roll it back up when I am finished) It works pretty well sometimes but last night was not one of those times. tried a W2UP rotatable Loop which lost all directivity when I ran some radials out in its direction. A VE3DO loop (no joy at all) I just had my mp1000 tweaked and have a 756 pro II and don't think either of them has an rx problem. Talked to Lee K7TJR about his antennas and because my tower sits almost smack dab in the center of my lot he didn't seem to think it would work well even if I were to detune the tower. I'm not sure that a K9AY or SAL would work for the same reasons. Like you I think I will just take down the inverted L. I learned quite a bit from some of the comments you got. I didn't fix anything but definitely know a lot of things that won't work. It was not particularly reassuring that when AA1K was here last year, I asked him if he thought a choke at the feed point would help anything? He said he didn't think one was needed on a vertical. Then I asked what else I could do he suggested that I might want to consider putting up a FOR SALE sign. Thanks again for sharing your results. 73 Chet N4FX KP4EAJ, VP2A, ZD8W, VQ9Xx, KL7AIZ, KG4ZO, N6Zo/HH9 N6ZO/6Y5 -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Rob Atkinson Sent: Sunday, December 30, 2018 9:52 AM To: topband@contesting.com Subject: Re: Topband: Inverted L improvement question - Part 2 Hmmmyou DID relocate or rebuild your ground system so it converges on a point below the bottom of the 100 foot tall wire right? I mean, you aren't using the 43 foot vert. ground system with the 100' wire? A series fed vertical isn't rocket science so let's not over think this. If it doesn't work well it is probably inefficient. I'd make sure your ground system is adequate. No, you can't use an existing ground system that converges on a point 30 or 40 feet away from the 100' wire. Yes, I've had people ask me if they can do that, so it is worth mentioning. You can go the elevated route, but it is _critical_ that it be constructed correctly to adequately replace a full ground system at or below grade. You need four radials parallel to earth extending out 90 degrees from each other and their lengths must be equal and 90 degrees long (1/4 w.) at frequency. The ends must be h.v. insulated. They should be elevated 20 feet on 160 m. to completely de-couple from earth. 73 Rob K5UJ _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus _ 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: Inverted L improvement question - Part 2
I'm not sure that a K9AY or SAL would work for > the same reasons. > > Like you I think I will just take down the inverted L. I learned quite a > bit from some of the comments you got. I didn't fix anything but > definitely > know a lot of things that won't work. It was not particularly reassuring > that when AA1K was here last year, I asked him if he thought a choke at the > feed point would help anything? He said he didn't think one was needed on > a > vertical. Then I asked what else I could do he suggested that I might want > to consider putting up a FOR SALE sign. > > Thanks again for sharing your results. > > 73 > > > Chet N4FX KP4EAJ, VP2A, ZD8W, VQ9Xx, KL7AIZ, KG4ZO, N6Zo/HH9 > N6ZO/6Y5 > > > > > > > -Original Message- > From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Rob > Atkinson > Sent: Sunday, December 30, 2018 9:52 AM > To: topband@contesting.com > Subject: Re: Topband: Inverted L improvement question - Part 2 > > Hmmmyou DID relocate or rebuild your ground system so it converges > on a point below the bottom of the 100 foot tall wire right? I mean, > you aren't using the 43 foot vert. ground system with the 100' wire? > A series fed vertical isn't rocket science so let's not over think > this. If it doesn't work well it is probably inefficient. I'd make > sure your ground system is adequate. No, you can't use an existing > ground system that converges on a point 30 or 40 feet away from the > 100' wire. Yes, I've had people ask me if they can do that, so it is > worth mentioning. > > You can go the elevated route, but it is _critical_ that it be > constructed correctly to adequately replace a full ground system at or > below grade. You need four radials parallel to earth extending out > 90 degrees from each other and their lengths must be equal and 90 > degrees long (1/4 w.) at frequency. The ends must be h.v. insulated. > They should be elevated 20 feet on 160 m. to completely de-couple from > earth. > > 73 > Rob > K5UJ > _ > Searchable Archives: http://www.contesting.com/_topband - Topband > Reflector > > > --- > This email has been checked for viruses by Avast antivirus software. > https://www.avast.com/antivirus > > _ > Searchable Archives: http://www.contesting.com/_topband - Topband > Reflector > _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Inverted L improvement question - Part 2
x don't waste your time calling, rx broken N4FX No ears N4FX Unmanned beacon station?? N4FX Big signal does not hear N4fx code reader failure??? N4FX op asleep at key??? N4fx where is he listening?? is he even listening? N4FX working crossband??? I have tried a 200 foot BOG which actually runs across the street and cars drive over it. (I roll it out after dark but not a busy street). And roll it back up when I am finished) It works pretty well sometimes but last night was not one of those times. tried a W2UP rotatable Loop which lost all directivity when I ran some radials out in its direction. A VE3DO loop (no joy at all) I just had my mp1000 tweaked and have a 756 pro II and don't think either of them has an rx problem. Talked to Lee K7TJR about his antennas and because my tower sits almost smack dab in the center of my lot he didn't seem to think it would work well even if I were to detune the tower. I'm not sure that a K9AY or SAL would work for the same reasons. Like you I think I will just take down the inverted L. I learned quite a bit from some of the comments you got. I didn't fix anything but definitely know a lot of things that won't work. It was not particularly reassuring that when AA1K was here last year, I asked him if he thought a choke at the feed point would help anything? He said he didn't think one was needed on a vertical. Then I asked what else I could do he suggested that I might want to consider putting up a FOR SALE sign. Thanks again for sharing your results. 73 Chet N4FX KP4EAJ, VP2A, ZD8W, VQ9Xx, KL7AIZ, KG4ZO, N6Zo/HH9 N6ZO/6Y5 -Original Message- From: Topband [mailto:topband-boun...@contesting.com] On Behalf Of Rob Atkinson Sent: Sunday, December 30, 2018 9:52 AM To: topband@contesting.com Subject: Re: Topband: Inverted L improvement question - Part 2 Hmmmyou DID relocate or rebuild your ground system so it converges on a point below the bottom of the 100 foot tall wire right? I mean, you aren't using the 43 foot vert. ground system with the 100' wire? A series fed vertical isn't rocket science so let's not over think this. If it doesn't work well it is probably inefficient. I'd make sure your ground system is adequate. No, you can't use an existing ground system that converges on a point 30 or 40 feet away from the 100' wire. Yes, I've had people ask me if they can do that, so it is worth mentioning. You can go the elevated route, but it is _critical_ that it be constructed correctly to adequately replace a full ground system at or below grade. You need four radials parallel to earth extending out 90 degrees from each other and their lengths must be equal and 90 degrees long (1/4 w.) at frequency. The ends must be h.v. insulated. They should be elevated 20 feet on 160 m. to completely de-couple from earth. 73 Rob K5UJ _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Inverted L improvement question - Part 2
Todd If you are interested in experimenting, you could try a K2AV folded counterpoise under that inverted L. If installed as recommended, it will provide a decent counterpoise system. One advantage to the FCP is that it is possible to also end fed the system, should that be a requirement. I was using an inverted L against a tower with random grounding--antenna R was up in the 80 ohm range. Over the K2AV, and away from the tower the antenna R dropped to 26 ohms. It works good enough for now. I have very poor ground conductivity, and running a large radial field would be hard over rocky sandy soil. I also fed the L over the FCP for 80 meters, an L Network is switched in to match the antenna, and the FCP counterpoise is changed over to 80 meters using surplus Russian vacuum relays. _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Inverted L improvement question - Part 2
Hi Rob, You ask some good questions and make some interesting observations. Nope, it is the same radial system. I don't have a reasonable way (time/money/effort) to create a whole new 50-60 wire buried radial system for this experiment. I just disconnected the 43' vertical from the radial mounting plate and connected the 100' vertical wire to the output of the remote tuner. Simply replaced one radiator with the other. The 100' tall wire's tree branch anchor is, at the apex, offset from the center of the radial field by maybe 15'. So, being that it is wire, I just angled it over and connected it. My figuring (probably bad) was that a 15' horizontal run over a 100' drop isn't a very steep angle and I'd work with what I had. I suspected that could be an issue when it just didn't play at all. That is when I rigged up the elevated radials. Several links folks have pointed me to describe the elevated radials and I thought I'd give that a try instead to salvage the operation. Not a big deal since this is really just a learning experience and even failure is learning. At this point I can A/B antenna switch between the 43' using buried radials and the 100' using the elevated radials. The elevated radials don't meet your design criteria either. Only three of them at roughtly equal spacing around the compass. I cut them at 135' long. They aren't perfectly parallel to the earth's surface due to support points being at uneven heights. They certainly aren't at 20' from the ground. The wire is insulated but they are just tied off to supports at the ends. All in all a complete mess of efficiency. Throwing up something temporary in the winter rain/cold has some limitations that aren't conducive to good 160m operation, it appears. :-) I did operate in the Stew Perry last night using both antennas to transmit and the BOG to receive. The BOG worked better than I expected, notice I didn't say "great". The 100' performed poorly compared to the 43' using CONUS distances as a benchmark. No EU or JAs heard at my QTH... I think I'll pull the 100' wire and supporting stuff down. It doesn't seem worth the trouble since it isn't providing any additional benefit. Nothing is easy at 160m. :-) But it has been fun. Thanks for the insight. 73, Todd - NR7RR >Hmmmyou DID relocate or rebuild your ground system so it converges >on a point below the bottom of the 100 foot tall wire right? I mean, >you aren't using the 43 foot vert. ground system with the 100' wire? >A series fed vertical isn't rocket science so let's not over think >this. If it doesn't work well it is probably inefficient. I'd make >sure your ground system is adequate. No, you can't use an existing >ground system that converges on a point 30 or 40 feet away from the >100' wire. Yes, I've had people ask me if they can do that, so it is >worth mentioning. >You can go the elevated route, but it is _critical_ that it be >constructed correctly to adequately replace a full ground system at or >below grade. You need four radials parallel to earth extending out >90 degrees from each other and their lengths must be equal and 90 >degrees long (1/4 w.) at frequency. The ends must be h.v. insulated. >They should be elevated 20 feet on 160 m. to completely de-couple from >earth. >73 >Rob >K5UJ _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Inverted L improvement question - Part 2
Hmmmyou DID relocate or rebuild your ground system so it converges on a point below the bottom of the 100 foot tall wire right? I mean, you aren't using the 43 foot vert. ground system with the 100' wire? A series fed vertical isn't rocket science so let's not over think this. If it doesn't work well it is probably inefficient. I'd make sure your ground system is adequate. No, you can't use an existing ground system that converges on a point 30 or 40 feet away from the 100' wire. Yes, I've had people ask me if they can do that, so it is worth mentioning. You can go the elevated route, but it is _critical_ that it be constructed correctly to adequately replace a full ground system at or below grade. You need four radials parallel to earth extending out 90 degrees from each other and their lengths must be equal and 90 degrees long (1/4 w.) at frequency. The ends must be h.v. insulated. They should be elevated 20 feet on 160 m. to completely de-couple from earth. 73 Rob K5UJ _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Inverted L improvement question - Part 2
Hi Grant and Todd I suggest there is also potential for a 4th problem - mutual coupling between the vertical wire and supporting tree. Any such coupling would be smaller for the 43 ft vertical if it was located further away from the tree. It would be interesting to see if there is any noticeable change in the SWR curve and performance by increasing the distance between the vertical wire and tree trunk. But I also appreciate that space and other factors may preclude Todd from doing this. 73, Brian VK3MI Message: 11 Date: Sat, 29 Dec 2018 09:00:03 -0800 From: Grant Saviers To: Todd Goins , TopBand List Subject: Re: Topband: Inverted L improvement question - Part 2 Message-ID: Content-Type: text/plain; charset=utf-8; format=flowed Problem #1. The swr indicates about a 140Khz plus < 2:1 bandwidth (2 * 1880-1810) which implies a high radial resistance. Are the elevated radials fully insulated from trees, not contacting foliage, etc? Add three more. Problem #2. Your coiled coax choke may be making things worse. Check out the just released designs from K9YC and build one. 17 turns RG400 on one FT240-31. Problem #3. The increased gain of the T may be causing BCB desense of the 7300. You need a BCB filter. Also the poor choke may be letting a lot of common mode noise into the antenna. Grant KZ1W _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Inverted L improvement question - Part 2
Exactly! You have a lot of loss in your ground (or something), Todd. Perhaps it's the lack of a proper feedline choke. 73, Mike www.w0btu.com On Sat, Dec 29, 2018, 11:00 AM Grant Saviers wrote: > Problem #1. The swr indicates about a 140Khz plus < 2:1 bandwidth (2 * > 1880-1810) which implies a high radial resistance. Are the elevated > radials fully insulated from trees, not contacting foliage, etc? Add > three more. > Problem #2. Your coiled coax choke may be making things worse. Check > out the just released designs from K9YC and build one. 17 turns RG400 > on one FT240-31. > Problem #3. The increased gain of the T may be causing BCB desense of > the 7300. You need a BCB filter. Also the poor choke may be letting a > lot of common mode noise into the antenna. > > Grant KZ1W > > > > On 12/28/2018 19:39 PM, Todd Goins wrote: > > A person emailed me to ask if I could take SWR readings at the rig > without > > a tuner. Since my antenna analyzer is non-op due to the AM station > nearby. > > The feedline is about 140' of LMR-240. > > > > Here is the indicated SWR at the 7300: > > 1.810 1.2:1 > > 1.830 1.3:1 > > 1.850 1.5:1 > > 1.870 1.8:1 > > 1.900 2.3:1 > > 1.940 3.0:1 > > > > Todd - NR7RR > > > > On Fri, Dec 28, 2018 at 7:30 PM Todd Goins wrote: > > > >> Charlie, > >> > >> Yeah, I know the 100w is not ideal. This is night #2 with the elevated > >> radials on the 100' vertical. I spent every day last week trying to use > the > >> 100' vertical against my buried radial field. It was horrible on > transmit > >> and mostly deaf (high noise) on receive. The attenuator didn't help, it > >> just isn't hearing stations. My 43' vertical top loaded with 90' of > >> horizontal wire is way, way more effective. > >> > >> I'm using a 230' BOG as my primary receive antenna right now but I can > >> switch in the transmit antenna to listen just by throwing a switch. > >> > >> I'll stick with this 100' antenna for a while and try to use it this > >> weekend on the Stew Perry but I have a feeling I'll be back with the 43' > >> before it is over. > >> > >> Thanks, > >> 73 > >> Todd - NR7RR > >> > >> On Fri, Dec 28, 2018 at 7:19 PM charlie carroll wrote: > >> > >>> Todd: > >>> So, I might shorten the antenna up a bit to get the lowest SWR point a > >>> bit higher in the band. But, as it sits right now, your SWR is not > >>> indicating a problem. You're talking only a 100 watts which gives you > at > >>> least 1 strike. I would play with it as is for a few days and get some > >>> idea as to how well you are hearing and how well you are transmitting. > >>> > >>> Without detailing you, 160 is a place where you need patience and/or a > >>> low-noise receiving antenna. Plus, you also need to know whether you > are > >>> being affected by local noise sources. Another reason why I encourage > you > >>> to spend more time evaluating the antenna. > >>> > >>> 73 charlie, k1xx > >>> > >>> On 12/28/2018 10:07 PM, Todd Goins wrote: > >>> > >>> Hi Charlie, > >>> > >>> I can measure SWR at the rig. Feedline is about 140' of LMR240 coax. > >>> > >>> SWR at: > >>> 1.810 1.2:1 > >>> 1.830 1.3:1 > >>> 1.850 1.5:1 > >>> 1.870 1.8:1 > >>> 1.900 2.3:1 > >>> 1.940 3.0:1 > >>> > >>> I wasn't too worried about the choke situation but I connected in-line > >>> what I had on hand, figured it wouldn't hurt. Mike had just asked what > I > >>> was using so I let him know. I'm not having any symptoms of RF in the > shack > >>> but I'm only running 100 watts. > >>> > >>> 73, > >>> Todd - NR7RR > >>> > >>> > >>> On Fri, Dec 28, 2018 at 6:56 PM charlie carroll wrote: > >>> > Todd: > So, what do you expect the air-wound choke to do for you? Many, many, > many antennas operate fine without a choke. Don't get yourself > wrapped > around the axle that the antenna won't work without a "correct" choke. > > What's SWR are you measuring at the transmitter? How long is the > feedline? Sure, it would be better to know what the Resistance and > reactance are. But, SWR will give you some idea as to where you are > at. I > think right now, you don't really know what your ground truth is. > Tell me > the SWR at 1.8, 1.85, 1.9, etc. > > 73 charlie, k1xx > > > > On 12/28/2018 9:30 PM, Todd Goins wrote: > > Hi Mike, > > Oh, I would totally believe that the air-wound choke is ineffective at > 160m. It just happens to be what I had available to use when I rigged > up > the elevated radials in the cold rain yesterday. I figured I'd put it > in > line just in case. > > Thanks for the choke links, I will read the info on those sites. > > The air-wound choke is what I'm using when I'm feeding the antenna > using > the elevated radials. When I was testing using my buried radial field > it is > a different setup. There I have a DX Engineering radial plate that > neatly > ties everything (remote tuner, and DX
Re: Topband: Inverted L improvement question - Part 2
On Sat, Dec 29, 2018 at 8:59 AM Grant Saviers wrote: > Problem #1. The swr indicates about a 140Khz plus < 2:1 bandwidth (2 * > 1880-1810) which implies a high radial resistance. Are the elevated > radials fully insulated from trees, not contacting foliage, etc? Add > three more. > Problem #2. Your coiled coax choke may be making things worse. Check > out the just released designs from K9YC and build one. 17 turns RG400 > on one FT240-31. > Problem #3. The increased gain of the T may be causing BCB desense of > the 7300. You need a BCB filter. Also the poor choke may be letting a > lot of common mode noise into the antenna. > > Grant KZ1W > Hello Grant, Thanks for the input. I've made a couple of modifications this morning. I can't make that choke today because I don't have the FT240-31 but I'll check out that design and look into ordering the parts. Sounds easy enough to build though. Yes, the BCB signal on the large wire is intense. When attempting to use it as a receiving antenna I have to run the attenuator and often dial out some RF Gain as well. Nasty stuff. I'll see about getting a BCB filter if for nothing else but to be able to use the antenna analyzer. I've looked at many designs I could build but they almost all have a cutoff freq above the 160m band. Not what I need... I raised the feedpoint to about 12' above ground surface and the radials are similarly elevated for their 130' length. The radial wire is insulated but it does use some (leafless) tree branches as supports. I have no way to add three more elevated 130' radials at this time. Good idea though. Raising the feedpoint did change the SWR readings at the rig. The 2:1 range is quite a bit narrower, which is an improvement, I guess. Here are the new readings. Indicated SWR at the 7300: 1.810 1.3:1 1.830 1.6:1 1.850 1.8:1 1.870 2.3:1 1.900 2.8:1 1.940 greater than 5:1 I'm looking forward to trying it out tonight in the Stew Perry. I still have the 43' L to fall back on if the performance has not improved. Thanks for the help. 73, Todd - NR7RR > _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Inverted L improvement question - Part 2
Problem #1. The swr indicates about a 140Khz plus < 2:1 bandwidth (2 * 1880-1810) which implies a high radial resistance. Are the elevated radials fully insulated from trees, not contacting foliage, etc? Add three more. Problem #2. Your coiled coax choke may be making things worse. Check out the just released designs from K9YC and build one. 17 turns RG400 on one FT240-31. Problem #3. The increased gain of the T may be causing BCB desense of the 7300. You need a BCB filter. Also the poor choke may be letting a lot of common mode noise into the antenna. Grant KZ1W On 12/28/2018 19:39 PM, Todd Goins wrote: A person emailed me to ask if I could take SWR readings at the rig without a tuner. Since my antenna analyzer is non-op due to the AM station nearby. The feedline is about 140' of LMR-240. Here is the indicated SWR at the 7300: 1.810 1.2:1 1.830 1.3:1 1.850 1.5:1 1.870 1.8:1 1.900 2.3:1 1.940 3.0:1 Todd - NR7RR On Fri, Dec 28, 2018 at 7:30 PM Todd Goins wrote: Charlie, Yeah, I know the 100w is not ideal. This is night #2 with the elevated radials on the 100' vertical. I spent every day last week trying to use the 100' vertical against my buried radial field. It was horrible on transmit and mostly deaf (high noise) on receive. The attenuator didn't help, it just isn't hearing stations. My 43' vertical top loaded with 90' of horizontal wire is way, way more effective. I'm using a 230' BOG as my primary receive antenna right now but I can switch in the transmit antenna to listen just by throwing a switch. I'll stick with this 100' antenna for a while and try to use it this weekend on the Stew Perry but I have a feeling I'll be back with the 43' before it is over. Thanks, 73 Todd - NR7RR On Fri, Dec 28, 2018 at 7:19 PM charlie carroll wrote: Todd: So, I might shorten the antenna up a bit to get the lowest SWR point a bit higher in the band. But, as it sits right now, your SWR is not indicating a problem. You're talking only a 100 watts which gives you at least 1 strike. I would play with it as is for a few days and get some idea as to how well you are hearing and how well you are transmitting. Without detailing you, 160 is a place where you need patience and/or a low-noise receiving antenna. Plus, you also need to know whether you are being affected by local noise sources. Another reason why I encourage you to spend more time evaluating the antenna. 73 charlie, k1xx On 12/28/2018 10:07 PM, Todd Goins wrote: Hi Charlie, I can measure SWR at the rig. Feedline is about 140' of LMR240 coax. SWR at: 1.810 1.2:1 1.830 1.3:1 1.850 1.5:1 1.870 1.8:1 1.900 2.3:1 1.940 3.0:1 I wasn't too worried about the choke situation but I connected in-line what I had on hand, figured it wouldn't hurt. Mike had just asked what I was using so I let him know. I'm not having any symptoms of RF in the shack but I'm only running 100 watts. 73, Todd - NR7RR On Fri, Dec 28, 2018 at 6:56 PM charlie carroll wrote: Todd: So, what do you expect the air-wound choke to do for you? Many, many, many antennas operate fine without a choke. Don't get yourself wrapped around the axle that the antenna won't work without a "correct" choke. What's SWR are you measuring at the transmitter? How long is the feedline? Sure, it would be better to know what the Resistance and reactance are. But, SWR will give you some idea as to where you are at. I think right now, you don't really know what your ground truth is. Tell me the SWR at 1.8, 1.85, 1.9, etc. 73 charlie, k1xx On 12/28/2018 9:30 PM, Todd Goins wrote: Hi Mike, Oh, I would totally believe that the air-wound choke is ineffective at 160m. It just happens to be what I had available to use when I rigged up the elevated radials in the cold rain yesterday. I figured I'd put it in line just in case. Thanks for the choke links, I will read the info on those sites. The air-wound choke is what I'm using when I'm feeding the antenna using the elevated radials. When I was testing using my buried radial field it is a different setup. There I have a DX Engineering radial plate that neatly ties everything (remote tuner, and DX Engineering Maxi-core Feedline Current Choke) together at the feed point. Thanks for the comments and info. 73, Todd - NR7RR On Fri, Dec 28, 2018 at 5:57 PM Mike Waters wrote: Hi Todd, I'll bet the farm (if I had one) that your air-core choke is ineffective. Take at look athttp://www.karinya.net/g3txq/chokes to see what I mean. A very, very good common mode choke is the one I have on mine, fromhttp://audiosystemsgroup.com/RFI-Ham.pdf. There is no better material written on this subject, either in print or on the Internet. 73, Mikewww.w0btu.com On Fri, Dec 28, 2018 at 7:34 PM Todd Goins wrote: ... I do have a common mode choke at (near) the feed point. It may or may not be effective at 160m. It does work on 10-80m. It is about 25' of RG-8 coax wrapped around a 4" PVC pipe as a form. Perhaps not ideal... No RF
Re: Topband: Inverted L improvement question - Part 2
Those SWR readings seem to indicate a very large bandwidth, to the extent it might suggest that your ground resistance losses are swamping the antenna R radiation resistance. It would be nice to know the R value at resonance, where there is no J value. Too bad the analyzer is overloading. A simple BCB filter might help. Pete k1zjh _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Inverted L improvement question - Part 2
A person emailed me to ask if I could take SWR readings at the rig without a tuner. Since my antenna analyzer is non-op due to the AM station nearby. The feedline is about 140' of LMR-240. Here is the indicated SWR at the 7300: 1.810 1.2:1 1.830 1.3:1 1.850 1.5:1 1.870 1.8:1 1.900 2.3:1 1.940 3.0:1 Todd - NR7RR On Fri, Dec 28, 2018 at 7:30 PM Todd Goins wrote: > Charlie, > > Yeah, I know the 100w is not ideal. This is night #2 with the elevated > radials on the 100' vertical. I spent every day last week trying to use the > 100' vertical against my buried radial field. It was horrible on transmit > and mostly deaf (high noise) on receive. The attenuator didn't help, it > just isn't hearing stations. My 43' vertical top loaded with 90' of > horizontal wire is way, way more effective. > > I'm using a 230' BOG as my primary receive antenna right now but I can > switch in the transmit antenna to listen just by throwing a switch. > > I'll stick with this 100' antenna for a while and try to use it this > weekend on the Stew Perry but I have a feeling I'll be back with the 43' > before it is over. > > Thanks, > 73 > Todd - NR7RR > > On Fri, Dec 28, 2018 at 7:19 PM charlie carroll wrote: > >> Todd: >> So, I might shorten the antenna up a bit to get the lowest SWR point a >> bit higher in the band. But, as it sits right now, your SWR is not >> indicating a problem. You're talking only a 100 watts which gives you at >> least 1 strike. I would play with it as is for a few days and get some >> idea as to how well you are hearing and how well you are transmitting. >> >> Without detailing you, 160 is a place where you need patience and/or a >> low-noise receiving antenna. Plus, you also need to know whether you are >> being affected by local noise sources. Another reason why I encourage you >> to spend more time evaluating the antenna. >> >> 73 charlie, k1xx >> >> On 12/28/2018 10:07 PM, Todd Goins wrote: >> >> Hi Charlie, >> >> I can measure SWR at the rig. Feedline is about 140' of LMR240 coax. >> >> SWR at: >> 1.810 1.2:1 >> 1.830 1.3:1 >> 1.850 1.5:1 >> 1.870 1.8:1 >> 1.900 2.3:1 >> 1.940 3.0:1 >> >> I wasn't too worried about the choke situation but I connected in-line >> what I had on hand, figured it wouldn't hurt. Mike had just asked what I >> was using so I let him know. I'm not having any symptoms of RF in the shack >> but I'm only running 100 watts. >> >> 73, >> Todd - NR7RR >> >> >> On Fri, Dec 28, 2018 at 6:56 PM charlie carroll wrote: >> >>> Todd: >>> So, what do you expect the air-wound choke to do for you? Many, many, >>> many antennas operate fine without a choke. Don't get yourself wrapped >>> around the axle that the antenna won't work without a "correct" choke. >>> >>> What's SWR are you measuring at the transmitter? How long is the >>> feedline? Sure, it would be better to know what the Resistance and >>> reactance are. But, SWR will give you some idea as to where you are at. I >>> think right now, you don't really know what your ground truth is. Tell me >>> the SWR at 1.8, 1.85, 1.9, etc. >>> >>> 73 charlie, k1xx >>> >>> >>> >>> On 12/28/2018 9:30 PM, Todd Goins wrote: >>> >>> Hi Mike, >>> >>> Oh, I would totally believe that the air-wound choke is ineffective at >>> 160m. It just happens to be what I had available to use when I rigged up >>> the elevated radials in the cold rain yesterday. I figured I'd put it in >>> line just in case. >>> >>> Thanks for the choke links, I will read the info on those sites. >>> >>> The air-wound choke is what I'm using when I'm feeding the antenna using >>> the elevated radials. When I was testing using my buried radial field it is >>> a different setup. There I have a DX Engineering radial plate that neatly >>> ties everything (remote tuner, and DX Engineering Maxi-core Feedline >>> Current Choke) together at the feed point. >>> >>> Thanks for the comments and info. >>> 73, >>> Todd - NR7RR >>> >>> >>> On Fri, Dec 28, 2018 at 5:57 PM Mike Waters >>> wrote: >>> >>> >>> Hi Todd, >>> >>> I'll bet the farm (if I had one) that your air-core choke is ineffective. >>> Take at look athttp://www.karinya.net/g3txq/chokes to see what I mean. >>> >>> A very, very good common mode choke is the one I have on mine, >>> fromhttp://audiosystemsgroup.com/RFI-Ham.pdf. There is no better material >>> written on this subject, either in print or on the Internet. >>> >>> 73, Mikewww.w0btu.com >>> >>> On Fri, Dec 28, 2018 at 7:34 PM Todd Goins >>> wrote: >>> >>> >>> ... I do have a common mode choke at (near) the feed point. It may or may >>> not >>> be effective at 160m. It does work on 10-80m. It is about 25' of RG-8 coax >>> wrapped around a 4" PVC pipe as a form. Perhaps not ideal... No RF noted >>> in >>> the shack. >>> >>> 73, >>> Todd - NR7RR >>> >>> >>> _ >>> Searchable Archives: http://www.contesting.com/_topband - Topband Reflector >>> >>> >>> >>> >> _ Searchable Archives: http://www.contesting.com/_topband - Topband
Re: Topband: Inverted L improvement question - Part 2
Hi Mike, Oh, I would totally believe that the air-wound choke is ineffective at 160m. It just happens to be what I had available to use when I rigged up the elevated radials in the cold rain yesterday. I figured I'd put it in line just in case. Thanks for the choke links, I will read the info on those sites. The air-wound choke is what I'm using when I'm feeding the antenna using the elevated radials. When I was testing using my buried radial field it is a different setup. There I have a DX Engineering radial plate that neatly ties everything (remote tuner, and DX Engineering Maxi-core Feedline Current Choke) together at the feed point. Thanks for the comments and info. 73, Todd - NR7RR On Fri, Dec 28, 2018 at 5:57 PM Mike Waters wrote: > Hi Todd, > > I'll bet the farm (if I had one) that your air-core choke is ineffective. > Take at look at > http://www.karinya.net/g3txq/chokes to see what I mean. > > A very, very good common mode choke is the one I have on mine, from > http://audiosystemsgroup.com/RFI-Ham.pdf. There is no better material > written on this subject, either in print or on the Internet. > > 73, Mike > www.w0btu.com > > On Fri, Dec 28, 2018 at 7:34 PM Todd Goins wrote: > >> ... I do have a common mode choke at (near) the feed point. It may or may >> not >> be effective at 160m. It does work on 10-80m. It is about 25' of RG-8 coax >> wrapped around a 4" PVC pipe as a form. Perhaps not ideal... No RF noted >> in >> the shack. >> >> 73, >> Todd - NR7RR >> > _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Inverted L improvement question - Part 2
Hi Todd, I'll bet the farm (if I had one) that your air-core choke is ineffective. Take at look at http://www.karinya.net/g3txq/chokes to see what I mean. A very, very good common mode choke is the one I have on mine, from http://audiosystemsgroup.com/RFI-Ham.pdf. There is no better material written on this subject, either in print or on the Internet. 73, Mike www.w0btu.com On Fri, Dec 28, 2018 at 7:34 PM Todd Goins wrote: > ... I do have a common mode choke at (near) the feed point. It may or may > not > be effective at 160m. It does work on 10-80m. It is about 25' of RG-8 coax > wrapped around a 4" PVC pipe as a form. Perhaps not ideal... No RF noted in > the shack. > > 73, > Todd - NR7RR > _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Inverted L improvement question - Part 2
Sorry, I wasn't completely clear in my post. The elevated radials are not connected to the buried radial field. They are two separate entities. Now the elevated radials do sit above or cross some the buried radials in some places so I'm sure they do interact but they aren't directly connected together. I only have a finite space to work with and the tree limb I'm using to support the wire "is where it is". Everything I'm doing at this scale is a huge kludge or compromise but I'm just trying to optimize my situation as best I can. The BOG however sits nowhere near the radials. So, the 100' vertical has only ever been hooked to just the buried radials or the elevated radials at any one moment during my testing. I do have a common mode choke at (near) the feed point. It may or may not be effective at 160m. It does work on 10-80m. It is about 25' of RG-8 coax wrapped around a 4" PVC pipe as a form. Perhaps not ideal... No RF noted in the shack. 73, Todd - NR7RR _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Inverted L improvement question - Part 2
Hello Grant, Your advice is spot-on! Elevated radials MUST NOT be connected to ground. Perhaps that's one of the reasons why Todd's inverted-L is working so poorly. Another important thing is to have a GOOD choke balun right at the feedpoint. *We need to keep the current off of the feedline shield.* This is how I made my own inverted-L work, per the advice of many Topbanders a whole lot smarter than me: http://www.w0btu.com/160_meters.html (scroll down). It describes the common-mode choke. There are photos there (click the links). 73, Mike www.w0btu.com On Fri, Dec 28, 2018 at 6:49 PM Grant Saviers wrote: > Modeling I've done shows it a bad idea to have in ground and elevated > radials connected together, but that is not clear from what you > described. Then with the elevated separate, moving the feedpoint up at > least 8', to 12' is better and elevated radials run out at that height. > I think it is a tossup if the "flying V" feed is used - ie gain some > vertical wire length by feeding near ground and then angle the wires to > the the elevated ones say at 45 degrees. It doesn't hurt to have the > buried radials below the elevated but doesn't help either according to > NEC4.2 models I've tried. The elevated ones shield the currents enough > from the ground in the near field. > > Check out what N6LF has to say about elevated radials (if you haven't > already) antennasbyn6lf.com > > Then develop an swr curve with 5 watts from your rig. Better than nothing. > > Borrow a different antenna analyzer to try or put a quality BCB filter > on the input. You need one anyway. A two port VNA can calibrate out > the filter. > > It is also hard to compare antennas unless the A/B testing is real time. > This week proves that on 160, one night nada to EU, Thur night was > pretty good and I missed the killer opening on Wed according to PNW > reports. > > Grant KZ1W > > On 12/28/2018 15:35 PM, Todd Goins wrote: > > I originally started this thread and I want to once again thank everyone > > who provided input and advise both privately and on the reflector. > > > > So the 100' tall vertical with the 30' horizontal loading wire works > > **horribly**. I have about a week with it now every evening and it is > much, > > much poorer transmitting (and receiving, as expected I guess) than the > 43' > > vertical with the 90' horizontal. > > > > Since everyone was united in the opinion that I needed a dedicated > > receiving antenna I put out a 200' BOG (pointing east) with the > transformer > > and terminating resistor from DXEngineering. The BOG is really quiet > > (S1-S2) compared to the verticals and it hears "okay" but I wouldn't say > it > > was great by any means. The Stew Perry tomorrow will give me better > chance > > to evaluate it. > > > > Back to the 100' vertical. Since it wasn't working being tied into the > > buried radial field I was using for the 43' (PSK Reported showed dreadful > > performance) I decided to take a different approach and made it have an > > elevated feed point at about 7' above ground and I ran three 130' > elevated > > (also around 6' to 7' high) counterpoise wires. This antenna works a > little > > better but still not nearly as good as the 43'. > > > > Several people asked me to make R/Z measurements of the antenna at the > feed > > point. I'd love to provide that info but my Comet CAA-500 MarkII antenna > > analyzer is being totally killed on 160m by a 27.5KW AM broadcast station > > that is about 2 miles from my QTH. It will not work. The analyzer has > been > > fine on 6-40m and sometimes works on 80m but 160 is no-go. So I can't get > > the reactance and resistance values you all wanted. > > > > So, here is my question. The one easy modification I can make to the > > antenna, now that I have elevated radials connected, is that I can > elevate > > the feed point. I can raise it to about any height necessary. Would this > > make any difference? I would lengthen the horizontal wire by whatever > > distance I raised the feed point, right? Any ideas or am I just chasing > my > > tail? > > > > Thanks for reading and any advise you can give. > > 73, > > Todd - NR7RR > > _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Inverted L improvement question - Part 2
Modeling I've done shows it a bad idea to have in ground and elevated radials connected together, but that is not clear from what you described. Then with the elevated separate, moving the feedpoint up at least 8', to 12' is better and elevated radials run out at that height. I think it is a tossup if the "flying V" feed is used - ie gain some vertical wire length by feeding near ground and then angle the wires to the the elevated ones say at 45 degrees. It doesn't hurt to have the buried radials below the elevated but doesn't help either according to NEC4.2 models I've tried. The elevated ones shield the currents enough from the ground in the near field. Check out what N6LF has to say about elevated radials (if you haven't already) antennasbyn6lf.com Then develop an swr curve with 5 watts from your rig. Better than nothing. Borrow a different antenna analyzer to try or put a quality BCB filter on the input. You need one anyway. A two port VNA can calibrate out the filter. It is also hard to compare antennas unless the A/B testing is real time. This week proves that on 160, one night nada to EU, Thur night was pretty good and I missed the killer opening on Wed according to PNW reports. Grant KZ1W On 12/28/2018 15:35 PM, Todd Goins wrote: I originally started this thread and I want to once again thank everyone who provided input and advise both privately and on the reflector. So the 100' tall vertical with the 30' horizontal loading wire works **horribly**. I have about a week with it now every evening and it is much, much poorer transmitting (and receiving, as expected I guess) than the 43' vertical with the 90' horizontal. Since everyone was united in the opinion that I needed a dedicated receiving antenna I put out a 200' BOG (pointing east) with the transformer and terminating resistor from DXEngineering. The BOG is really quiet (S1-S2) compared to the verticals and it hears "okay" but I wouldn't say it was great by any means. The Stew Perry tomorrow will give me better chance to evaluate it. Back to the 100' vertical. Since it wasn't working being tied into the buried radial field I was using for the 43' (PSK Reported showed dreadful performance) I decided to take a different approach and made it have an elevated feed point at about 7' above ground and I ran three 130' elevated (also around 6' to 7' high) counterpoise wires. This antenna works a little better but still not nearly as good as the 43'. Several people asked me to make R/Z measurements of the antenna at the feed point. I'd love to provide that info but my Comet CAA-500 MarkII antenna analyzer is being totally killed on 160m by a 27.5KW AM broadcast station that is about 2 miles from my QTH. It will not work. The analyzer has been fine on 6-40m and sometimes works on 80m but 160 is no-go. So I can't get the reactance and resistance values you all wanted. So, here is my question. The one easy modification I can make to the antenna, now that I have elevated radials connected, is that I can elevate the feed point. I can raise it to about any height necessary. Would this make any difference? I would lengthen the horizontal wire by whatever distance I raised the feed point, right? Any ideas or am I just chasing my tail? Thanks for reading and any advise you can give. 73, Todd - NR7RR _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
Re: Topband: Inverted L improvement question - Part 2
Two 100 x 3 ft rolls of chicken wire were added this fall. I have about 45 radials, good conductivity, clear view, and the sump pump dumps out nearby. It is quiet in the country but the beverages are better. I am putting up a SAL30. It will be better for USA contests. The F/B is good enough that you can tell someone is calling. K9ZO From: Topband on behalf of Todd Goins Sent: Friday, December 28, 2018 5:35:53 PM To: TopBand List Subject: Topband: Inverted L improvement question - Part 2 I originally started this thread and I want to once again thank everyone who provided input and advise both privately and on the reflector. So the 100' tall vertical with the 30' horizontal loading wire works **horribly**. I have about a week with it now every evening and it is much, much poorer transmitting (and receiving, as expected I guess) than the 43' vertical with the 90' horizontal. Since everyone was united in the opinion that I needed a dedicated receiving antenna I put out a 200' BOG (pointing east) with the transformer and terminating resistor from DXEngineering. The BOG is really quiet (S1-S2) compared to the verticals and it hears "okay" but I wouldn't say it was great by any means. The Stew Perry tomorrow will give me better chance to evaluate it. Back to the 100' vertical. Since it wasn't working being tied into the buried radial field I was using for the 43' (PSK Reported showed dreadful performance) I decided to take a different approach and made it have an elevated feed point at about 7' above ground and I ran three 130' elevated (also around 6' to 7' high) counterpoise wires. This antenna works a little better but still not nearly as good as the 43'. Several people asked me to make R/Z measurements of the antenna at the feed point. I'd love to provide that info but my Comet CAA-500 MarkII antenna analyzer is being totally killed on 160m by a 27.5KW AM broadcast station that is about 2 miles from my QTH. It will not work. The analyzer has been fine on 6-40m and sometimes works on 80m but 160 is no-go. So I can't get the reactance and resistance values you all wanted. So, here is my question. The one easy modification I can make to the antenna, now that I have elevated radials connected, is that I can elevate the feed point. I can raise it to about any height necessary. Would this make any difference? I would lengthen the horizontal wire by whatever distance I raised the feed point, right? Any ideas or am I just chasing my tail? Thanks for reading and any advise you can give. 73, Todd - NR7RR _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector _ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
