Re: Topband: 2 wl loop, worth the effort?
Try putting a closed reflector wire under a 1 WL horizontal loop. Lay it on the ground or bury. Use insulated wire and size per typical loops…~+5% at design frequency. Experiment by listening to weak signals while opening and closing the ends of the reflector. At our latitude (64N) loops (and Inv-L’s) work well if a full size vert is unavailable. Some have suggested it’s due to our tilted Ionosphere. That’s been my experience on 40-160. 73, Gary NL7Y _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Fwd: ARRL Board meets next week - I'm looking for input
I told myself when I started Amateur Radio I was going to be a Goose…where every day’s a new day. No awards, just work who you can, when you can, any way you can. So now when I hear DX or there’s a contest I try to make a contact if it’s of interest. As I say, that way every day and contact’s a new one. 73, Gary NL7Y _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: SP test - Awful condx
Poor also from Fairbanks, Ak. Listened both nights off and on. But in the end it was the burning end of my Inv-L that called timeout. Apparently my coated stranded wire had a covering defect at the far end where it was suspended in a tree…the voltage node melted the pull-up rope and down it came/SWR shot up/amp went into safe mode (Alpha 8410). And this was at -12F with everything covered with hoar frost. I’ve never had this happen before (I thought ice was a good insulator) but now I know what to look for at rebuild. 73, Gary NL7Y _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: tool for install radials
Hi John. Find a piece of wood, maybe a 2x4 and saw a slot in one end width-wise deep enough to firmly hold a partially inserted staple without it bending. Push or drive with a hammer against the 2x4 and force the staple into the ground over the wire flush with the end of the wood. Remove the wood (might need to tip sideways to release the staple if it’s tight in the slot), turn the wood 90 deg, and push down again to finish implanting the staple. Might work, never done it. 73, Gary NL7Y is there a simple , not overly expense tool to set land scape staples while standing?? at 73, I do not want to go through being on my hands and knees driving the staples in with a hammer. thanks john w8wej _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: New 3 el 160m yagi at 7J4AAL
I guess we’ll hear this 160 season from 7J4AAL. Living mid-path USA-JA affords KL7’s the opportunity to receive both as W’s and others turn their attention to JA. Why not give it a try if one has the motivation, real estate, and resources? And about which antenna is better? His 160 beam on a hill will outperform what most of us will ever have available. I wonder what his noise floor will be, and if he employs receiving arrays? Source: http://www.cd-corp.com/english/ http://www3.ocn.ne.jp/~kan1/cy163tower.html 73, Gary NL7Y _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Rig Question
Fast forward a few years: http://lists.contesting.com/_3830/2001-11/msg00025.html I had the pleasure and unique experience to share a chair with Rich KL7RA, Chip K7JA, and others. Watching, listening, soaking in all I could of their radio techniques and pileup control was a once in a lifetime opportunity. Chip brought his rig of choice at that time for the contest…a Yaesu MK-V Field. Today it’s not at the top of most lists, but I still own, operate, and enjoy one. 73, Gary NL7Y On 6/19/2014 1:30 PM, Carl wrote: ** Perceptions, pressure, freebies all play into the picture. I wont disagree the K3 has a good receiver, especially for CW but GOOD DXpedition/contest ops have contended with worse for decades and set new records I remember when Chip, K7JA, paid me a visit in the early 80's carrying along a new Yaesu FT-101EE and broke all records in the ARRL SS by winning for the first time won both the Phone and the CW in the same year as first place high scorer. Much of this can be chalked up to a very good operator, second to a good location and rare multiplier, and lastly to the radio. The purists at the time teased Chip's use of an inexpensive rice box as the FT-101 was called back then. Few would even list today such a radio as something they used. Herb Schoenbohm., KV4FZ _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Rig Question
Paying for? Weight, eye candy, and interface? Oh, and a better behaved ALC. However, as I noted I didn’t fuss with much over 20M and SSB, so maybe that’s where the 990 excels. They are very nice to observe and operate. The primary receiver on my early 990 may have been maladjusted, as it was not superior to the secondary on weak CW in my QRN. Kenwood said today to send my TS-590 in (my $) for all upgrades to current specs (especially the ALC) on their parts and labor $0.10, plus they’ll return ship. How’s that for out of warranty product support? The market must be getting competitive. When I out my K3/P3 I may get another 590. 73, Gary NL7Y The 2nd receiver in the 990 is essentially a 590 receiver so that makes sense. I would be pretty upset if the main 990 receiver was no better than the 590. What are you paying for. …The main receiver in the 990 is supposed to be better than the 2nd rcv. Things that make you go h. Mike W0MU _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Rig Question
In my earlier comments I avoided direct comparisons between the TS-590S and K3. In my experience anyone maligning or questioning a K3/P3 is eventually in for a few bee stings, as that topic brings out a swarm of loyalists defending the hive. I was through this earlier this year on their group reflector. Many offered positive comments, some less so regarding my personal rig preferences and experience. It’s all good, however, and we’re still radio friends. I’ve owned two K3’s, and early and current model. It’s main advantage for me was at very narrow BW (80-100Hz) inside a 250Hz roofing filter, the K3’s recovered weak CW on a noisy band was audibly ‘cleaner’ than my 590, MK-V Field, and IC-765. The sigs could be heard on all during my recent tests this last winter, but the K3 was better at that extraction. At that width, the NB and NR aren’t of value in improving the reception. At wider BW or other modes, the K3 advantage diminishes for me. The rest of the time, BW, and modes I prefer the TS-590S on reception. Now with a potential ALC upgrade, it may be even better in my shack. My Alpha tolerates any spikes, but shouldn’t have to deal with them. I’ll leave it at this. Use what you like, love, or makes you most successful given the quality of your station and location. 73, Gary NL7Y _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Rig Question
Where is the TS-590 ALC fix described Mike? I have one and will have it done if it’s available. I also had a TS-990…the receiver performance (both primary and secondary) were no better over a month’s trial on 160-15M than my 590. Looks real good however. Eye candy usually does. I have a 6-month old K3 with most options. It still sits in its box after mid-winter service by Elecraft next to the new boxed P3/SVGA. The 590 is just too easy to use in comparison. 73, Gary NL7Y I'm scheduled to send my TS-590 to Kenwood for the ALC fix but I will not have to pay for the labor; just the shipping there. Mike N2MS _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Rig Question
TU Mike for the info. I’ll call them tomorrow. BTW, the 2nd receiver in my TS-990 was consistently better at extracting very weak CW on 40-160 (mainly steady eastern RU beacons on 40, EU CW on 80-160) than the main, and as you note, an equal to the 590. Kenwood service: KENWOOD AUTHORIZED SERVICE CENTER - PACIFIC 19501 East Walnut Drive South CITY OF INDUSTRY, CA 91748 Phone: 626-333-2443 http://fthgroupinc.com 73, Gary NL7Y Gary, Contact the Kenwood Service Center and give them your email address. They will then send you an email when they are ready to upgrade your rig. The secondary receiver in the TS-990 is essentially that of the TS-590. I did not bother to get the K3 Panadapter. I used a QS1R as a secondary receiver with the K3. I can view the whole HF spectrum with the QS1R. Mike N2MS _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Rig Question
On my 990 the 2nd receiver was consistently night after night better able to detect a weak CW sig on 40-160. Same settings on both receivers: different settings, AGC, no AGC, ATT, RF gain varied, it didn’t matter the race was won by the second. I didn’t fuss with SSB very much so that mode may yield different results. My TS-590 paralleled the 2nd in all the A/B tests, and would beat the 1st on the same weak signals as well. The weak were at or in a S3-9 noise floor before DSP NB was applied to clean things up. On 20M up the race winner may be different due to the conversion scheme in each rig, not sure as that wasn’t my winter goal at night in KL7. The 990’s APF seemed to be only a narrow filter that didn’t necessarily create an “AH HA!” moment like some applications of that technology in other radios like the K3. Both TS-590 and 990 suffer from Kenwood’s implementation of the DSP NB…when the signals rise, the DSP NB goes to sleep and the noise floor is elevated. If I get my TS-590’s ALC fixed, my K3 setup is history. 73, Gary NL7Y The main receiver in the 990 is supposed to be better than the 2nd rcv. Things that make you go h. Mike W0MU _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Not so good in the contest last night
And here’s why…http://www.alaskadispatch.com/video/video-northern-lights-dance-above-fairbanks-alaska Was SP from 0700-1000. Lots of S’ing, no P’ing while listening to my TS-590 in scan mode. Maybe tonight. I have a fresh Voodoo chicken to swing in the shack. 73, Gary NL7Y _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Contest in progress - few signals
Still poor in central KL7. Maybe later. Aurora’s heating up, so maybe never: http://www.swpc.noaa.gov/pmap/index.html GL es 73, Gary NL7Y _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: Fwd: Contest in progress - few signals
Hi ! Bad condition ... only W1UE, WE3C = QSO W3LPL, K3LR copy, calling, but no QSO Aurora ! http://www.tesis.lebedev.ru/magnetic_storms.html See on HF GL in ARRL DX Contest 73! de UR5IFB Суббота, 15 февраля 2014, 19:29 -09:00 от Gary and Kathleen Pearse pea...@gci.net: Still poor in central KL7. Maybe later. Aurora’s heating up, so maybe never: http://www.swpc.noaa.gov/pmap/index.html GL es 73, Gary NL7Y _ Topband Reflector Archives - http://www.contesting.com/_topband С уважением, ur5...@mail.ru _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Ice
I believe OH8X had one or more “hammers” mounted to their 160 Yagi to help remove the ice buildup. Sadly their extraordinary effort recently fell victim to winds and reportedly torque: http://dx-world.net/2013/oh8x-tower-collapse/ Not sure what the answer is. My Puny 3-el SteppIR with fiberglass elements and retracted innards survived a November ice storm, gusts 60-70 reported locally, and a direct hit to the director by a falling tree and the 160 Inv-L wire. One bracket is bent some, the boom is bent some, but it still works. Repairs when it’s warmer. Take care, there’s more on the way as far as Lower 48’s stormy WX: http://www.weatherstreet.com/states/gfsx-sfc-temperature-and-wind-forecast.htm http://www.weatherstreet.com/states/gfsx-slp-forecast.htm 73, Gary NL7Y _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: circular polarization on 160m -BTW
Here’s a recent link from Ed KL7UW regarding his experience with Adaptive Polarity Reception: http://www.kl7uw.com/LINRAD.htm We were discussing the K3 and dual receiver diversity mode, and I had asked him about his EME and polarity antennas. 160M did come into the conversation as well. Might not be an end all answer but it’s a start. 73, Gary NL7Y BTW - does anyone know if the EME boys employ circular polarization? 73, Charlie, K4OTV _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Yikes! Heavy snow, freezing fog and 23 degrees F in Raleigh, NC
I keep a Honda EU 2000i genset (http://powerequipment.honda.com/generators/models/eu2000i) in the house for emergencies. We (Fairbanks, Ak.) had a wind and ice storm in November…lost my 160 wires for a while, two trees hit the house, and another broke the power line for over a couple days. The little Honda was enough to keep the Toyo oil stoves going and lights available. On Eco mode they’ll run a gallon of gas for 8-10 hrs easy. And they only weigh ~50# so can be carried about. It’ll run a barefoot ham station in an emergency as well. 73 and hunker down folks, Gary NL7Y Hi, Bill! Well, it's bad out there! Lots of gridlock on the roads and now the weather people are calling for 1/2 inch to 3/4 inch of ICE! That WILL bring the power down. Don’t' thimk I'm able to get my generator going, altho ugh it has bropu ght me through a few ice storms and a hurricane in the past but I'm too crippled now to; foo; with it! I'll just have to hunker down and hope for the best. I do have my gas logs. flashlights etc. If my ship comes in, I'd like to get a whole house generator with a transfer switch and electric start tho;at run's from natural gas but that doesn' help me right now! Take care and stay warm, Bill 73, Charlie, K4OTV _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Anyone purchased the ARRL book on Short Antennas for160???
I've built them for 40 and 80 via his modeling years ago. Fed both up high, and both down low. High feed 'seemed better', but no real way to tell. Worked a RU station on 80 from KL7 so they do emit a signal. It was a good aerial, easy to build, with some vertical component to the pattern. On 160 it may take some bending. Fed low it's a vert with an elevated radial. Two would be better, but then so would four and so on. 73, Gary NL7Y Wouldn't feeding it up high in the corner like that at least eliminate the need for radials? 73, Mike www.w0btu.com _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Anyone purchased the ARRL book on Short Antennas for160???
Oh, I left out the RU was in Antarctica. 73, Gary NL7Y I've built them for 40 and 80 via his modeling years ago. Fed both up high, and both down low. High feed 'seemed better', but no real way to tell. Worked a RU station on 80 from KL7 so they do emit a signal. It was a good aerial, easy to build, with some vertical component to the pattern. On 160 it may take some bending. Fed low it's a vert with an elevated radial. Two would be better, but then so would four and so on. 73, Gary NL7Y Wouldn't feeding it up high in the corner like that at least eliminate the need for radials? 73, Mike www.w0btu.com _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Anyone purchased the ARRL book on Short Antennas for160???
Found paper logs from July 1997…it was VP8CTR on 3796 SSB at our SR, and a Ukranian base not RU. Still, Cebik's L worked. 73, Gary NL7Y That's a good one for 80m from KL7! FB! 73, Charlie, K4OTV Oh, I left out the RU was in Antarctica. _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Radial Question
I’d run a test wire under the house and connect it to the rig. Listen for noise. Then connect to house ground and see if noisy. Compare that with each existing elevated radial for QRN. Here in Fairbanks anything through the home or grounded to the house or tower on 160 is worse than my ungrounded elevated radials. One elevated radial (of 8) near the power line is the noisiest. I disconnect it when it gets bad. 73, Gary NL7Y _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Wideband interference
I may be overreaching here but…in learning some of the new features of my K3/P3 with SVGA card and remote terminal I came across the screen snap or hold feature. If that image can be exported to the Utility program (or ???), saved, and maybe printed would it be possible to go portable and hunt for a similar noise signature? The reason I ask is that the local utility company owns a Radar Engineers receiver. They came to my shack, hooked up to my antennas and took a noise signature on the oscilloscope, and went hunting. They soon found the offending signal and fixed. Might be worth a try if one has a K3/P3 and the feature I describe does work. I’ve not tried it yet. 73, Gary NL7Y I've had many helpful private emails from folks who've seen/listened to what I posted. An RFI occurrence may or may not have a characteristic fingerprint, but you're not going to know unless you ask around or search the Web for a similar recording. If someone posted a recording of interference similar to what I've personally identified in the past, I could certainly respond with my past findings and potentially help them. In any event, this is the first step I choose to take before heading out the door in the dark and bitter cold weather to snoop around the surrounding area. But thanks for your encouraging finger pointing to do just that. Barry N1EU _ Topband Reflector Archives - http://www.contesting.com/_topband
Topband: 160 Test Aurora
Finished rebuilding my windstorm destroyed Inv-L Sat eve around 6pm in the dark headlamp on. Twenty above and warm. Snow and four downed trees so had to crawl around to hang new cords and elevated wires. Tuned up nice and low at 1830 and heard some ‘6’s, ‘7’s, a displaced 9, and KH6LC above the S4-5 floor. Good sign. Took a nap. Big mistake. By 0600 on the Band had died in Fairbanks @ 64 North…the Aurora overhead was a “Level 7” and that means take 2 big ones and go back to bed. The P3 bandscope looked like a nice blue waterfall with no falling CW debris. K3 was signal silent. The JA’s were chirping on 40 so it wasn’t the station or antenna. Maybe the Big Stew will be better. 73, Gary NL7Y _ Topband Reflector Archives - http://www.contesting.com/_topband
Re: Topband: Effect of trees- tree appreciation
Thank you all for the replies regarding the T versus L rebuild for my 160 antenna. I'm on a 120x120' city lot in Fairbanks. For fun look me up in QRZ, under 'Detail' zoom in for a satellite view via Google, then switch to a street view to see the trees. The motorhome is gone, the motorcycle is replaced with another, and the tower and trees still stand. The T would be strung between two spruce trees to the W of the home. Not the best scenario as the available tree spacing is a close ~75', the T wires would be touching the top of each tree trunk, and any excess for trim would drop down next to each trunk as well. A breeze would flex the trees and cause the vertical portion to rise and fall possibly affecting tuning. The L (mimicking my former 160 antenna that came down with a blown tree) would climb a 75-80' tree adjacent to the SW corner of the home, be held away 5-7' from the trunk via branches except for the very top, and the remaining ~55' horizontal portion would head towards the street to the south but not reach the support, again at 75-80'. Eight tuned radials at ~15' are strewn where possible around the property. After some thought and your discussion, I think I'll repeat the L as it's easy to shoot the support ropes from the house roof. The T would be harder, and one end would be close to the power line that adjoins the north edge of the property. Adjusting resonance for the T would require lowering the whole deal a few times from both supports. Adjusting the L is simpler and only requires loosening the horizontal leg and shortening or lengthening the base of the vertical part. Plus I already have a big feed line choke and 3:1 matching unit built from the previous setup. We'll see what happens, 73, Gary NL7Y _ Topband Reflector
Re: Topband: Effect of trees- tree appreciation
Where are the high voltage points in a T antenna? I have the choice of putting up either a new T between two trees, or an L again on 160M. The ends of the T would by necessity be strung over and go down 20-30' alongside the two supporting trees. The L would parallel a tree and bend over at around 75-80'. The horizontal end of the L would end up 20-30' from its tree support. I'd reuse my 8 tuned elevated radials, plus maybe a couple more. Suggestions? Sometimes high angle works better in our tilted ionosphere at 64N. 73, Gary NL7Y _ Topband Reflector
Re: Topband: Effect of trees
It's that time of year when trees and temps become Topband topic. Propagation must be poor. Until the supporting tree blew down, my Inv-L for 160 required shortening of the L in the Fall when the supporting and surrounding trees froze along with the ground below. However, in mid-winter if the air temp rose above freezing for a spell (rare in Fairbanks, but…) I'd have to lengthen the same element, but rarely more than 6. The total length change between summer and winter was typically about 12-18 for 135' of insulated #12 stranded house wire at 1835 MHz. The 1/4 WL L paralleled a White Spruce tree for half its length, folded over the top, but the end was never near another tree for about 20-30'. Winds would alter the SWR slightly as the horizontal portion changed distance relative to the 8 tuned elevated radials and ground (dirt) beneath. Without trees, some of us wouldn't have aerials. 73, Gary NL7Y _ Topband Reflector
Re: Topband: Magnetic Loops
I've had a Wellbrooke loop for a few years at 20' on a TV rotator. It nulls a single nearby QRN source NW at 300 deg true. EU is about 15-30 deg from here. When 160 or 80 are open over the N Pole, it often helps me hear the weak. It's less effective on multi-source QRN, but still helps at times if I rotate the loop to null the loudest noise and max the received signals. No room for other receiving antennas, and the loop ignores legal limit transmissions on a 120'x120' lot. What more can I ask? 73, Gary NL7Y I originated some discussion recently on this list and the guys that had tried this type of antenna all said that they would not buy one of them again. You can search the archives for the comments. Dave Harmon K6XYZ[at]sbcglobal[dot]net Sperry, Ok. All good topband ops know how to put up a beverage at night. _ Topband Reflector
Re: Topband: Magnetic Loops
Expecting this and given the proximity of my transmission antennas to the Wellbrook Loop (50-100'), I put 10 Type 31 slip-on beads over each end of the RG8-X feed and rotator control cable, and insulated the loop from the rotator with CPVC plumbing pipe. Did it help? Maybe. I get no feed line issues at legal limit in the shack. It simply was a shotgun reaction to a perceived potential problem. 73, Gary NL7Y This means CM noise on the feeder can be abnormally problematic, because more than the antenna is the antenna! This throws another wild card in the deck. 73 Tom All good topband ops know how to put up a beverage at night. _ Topband Reflector
Re: Topband: Magnetic Loops
Thanks Tom for the explanation. As always, this is a learning Reflector. Part of my location involves potential BCB, power line, adjacent home electronics, and of course the legal limit transmissions close to the loop/feed/rotator controller. Common mode supression is an absolute requirement on all lines. As to it's +- effect on the loop, well, as I mentioned, it was a shotgun process during the installation. Without common mode filtering on all cabling I couldn't operate. Such is the dilemma of the city dweller who has an S4-7 noise floor depending upon season. It's substantially worse in winter as explained below. I'm told that the effective RF ground in these parts of Alaska is 15+ meters down, and it'll find a way into the shack unless crowbarred at the door. Ground rods surrounded by 4-5' of winter frost and non-conductive soils are useless. 73, Gary NL7Y This doesn't mean loops will never work, or loops with poor feed systems will never make people happy. It just means it is almost impossible to correct a bad feed design by stringing beads or winding conventional chokes, even if you get up to 5,000 ohms. It is always far better to make the antenna with a correct feed system, because a proper feed has far less common mode response without any common mode foolery. 73 Tom All good topband ops know how to put up a beverage at night. _ Topband Reflector
Re: Topband: Trees (not the N6TR kind)
The following obs were an annual occurrence until my 85'+ support tree blew down this year. The 160 antenna described below was supported by the tree, and was no more than 4' from the trunk in the middle...the top an bottom were closer, ~1'. A wire Inv-L (#12 stranded THHN) with tuned elevated radials for 160, pruned in summer, dropped in resonance with each winter's freezing of the support, surrounding trees of similar height, and the ground below. It took up to 3' of vertical shortening (~2%) at the feed point to return it to 1.825, versus the same resonant point in summer. Sure, the ground freezes deeper with each passing winter month, but once pruned a month after freeze-up in early November, it would stay that way and not change until a major warming briefly defrosted only the tree(s). Meanwhile, the ground below froze at ever increasing depth, to typically about 4' max. Real RF ground is 10's of feet lower in our Interior Alaskan soils. I believe the tree(s) affected the wire antenna at some level. As to how much the RF was absorbed, or antenna pattern influeanced, I have no idea. 73, Gary NL7Y ___ Stew Perry Topband Distance Challenge coming on December 29th.
Re: Topband: Trees (not the N6TR kind)
Hi Dale and the Topband group. To trim the vertical portion, and return to original resonance every winter, I simply folded the wire closely back on itself in a flat bundle at the feed point and taped it tight. The overall length was shortened about 3' max. Just pulling in the wire to reduce the droop of the horizontal leg didn't appear to influence the resonance. Actual shortening by folding was required to reset the resonant freq. I didn't cut the wire because I wanted the longer length during pre-freezing conditions. Tree-supported Inv-L's and T's have their quirkiness versus true verticals in the clear I believe. 73, Gary NL7Y Hi Gary: Thats interesting. But did you trim it every winter? In 20 years only half the antenna would remain. I'm not trying to be a wise-guy, just wondering if you trimmed it annually. You bring up a good point and that is that conductivity in a tree trunk may change when it is frozen. 73 Dale - N3BN The following obs were an annual occurrence until my 85'+ support tree blew down this year. The 160 antenna described below was supported by the tree, and was no more than 4' from the trunk in the middle...the top an bottom were closer, ~1'. A wire Inv-L (#12 stranded THHN) with tuned elevated radials for 160, pruned in summer, dropped in resonance with each winter's freezing of the support, surrounding trees of similar height, and the ground below. It took up to 3' of vertical shortening (~2%) at the feed point to return it to 1.825, versus the same resonant point in summer. 73, Gary NL7Y ___ Stew Perry Topband Distance Challenge coming on December 29th.
Re: Topband: Trees (not the N6TR kind)
I used eight elevated tuned radials. They angled about 45 deg from about 4' at the feed to ~15' for their horizontal run. To initially tune, I used my MFJ-259 to feed a pair of radials (dipole), then cut the rest to match them. I set the system resonance via the length of the vertical/horizontal L. Your point is a good one. It may be that all I was doing was tuning the entire antenna system...radials and L portion...by adjusting the length of the L. I never fussed with the length of the radials after build, nor did I check them for tuned length. I have other 80-90' trees available, but now am considering a top loaded wire vert to see if it's more frequency stable as temps change. 73, Gary NL7Y Hi Gary, The frequency shift may have been partly due to the raised radials and relationship to the freezing earth. Frozen earth becomes an insulator so capacitive coupling between unfrozen earth and radials is getting less as temperatures drop. This can be overcome somewhat by also having on ground radials connected. This also helps the transmitted signal. Sorry you lost your tree. 73 Bruce-K1FZ The following obs were an annual occurrence until my 85'+ support tree blew down this year. The 160 antenna described below was supported by the tree, and was no more than 4' from the trunk in the middle...the top an bottom were closer, ~1'. A wire Inv-L (#12 stranded THHN) with tuned elevated radials for 160, pruned in summer, dropped in resonance with each winter's freezing of the support, surrounding trees of similar height, and the ground below. It took up to 3' of vertical shortening (~2%) at the feed point to return it to 1.825, versus the same resonant point in summer. 73, Gary NL7Y ___ Stew Perry Topband Distance Challenge coming on December 29th.
Re: Topband: Short Bogs
If we want to make an antenna electrically longer through cable velocity factor, it can't be done by the insulation slowing the wave inside the shield. 73 Tom In my experience, external insulation (through synthetic covering or frost) lowers the resonant frequency of wire antennas of a given length and height above ground. For example, I typically use 453/F as a starter length for insulated wire dipoles...it's higher for bare wire of the same AWG diameter. It may not be due to velocity factor (not sure of the reason), but it is observable and repeatable. 73, Gary NL7Y ___ Stew Perry Topband Distance Challenge coming on December 29th.
Re: Topband: raised radials
One thing I've wondered: are elevated radials more likely to pickup local QRN than those on the ground, or buried? The on-ground 160M loop antennas I've used for reception seemed quieter here than those that were elevated 15-20'. Before my 160 tree blew down this Fall and took the Inv-L antenna with it, I could walk around with an AM radio next to the 8 elevated tuned radials (4' at the antenna base angling up to ~15' in the trees) and pick up local hash and some minor AM BCB. Some radials were 'louder' than others, mainly those closest to potential noise sources like the AC power line or the house meter loop. I never tried that with on-ground radials as I had none to compare them with. The antenna base was ungrounded and fed through a custom wound UN-UN followed by a DXE VFCC-H10-A choke. There was no BCB in the shack end of the coax where I had slipped on 10 Type 31 ferrite beads, but there was still city QRN of course. 73, Gary NL7Y ___ Topband reflector - topband@contesting.com
Re: Topband: Fw: GAP VERTICAL QUESTION
FWIW, at one point on a 5 acre remote parcel I had a GAP Voyager, GAP Titan, 80/160 parallel Inv-L over 120/125' radials, a 160M Inv-V, a F-12 C-4SXL beam at 54', and homemade vertical fan dipoles for 10-40M. Tall 70-85' trees that later burned in a forest fire held up the wires. The GAPS were just that...always at the bottom of the RF food chain. The vertical dipoles were down in strength from the F-12 beam some, yet I heard and worked everything the beam did when compared. They are a good alternative to a vert on the same band if supports are available. I had verts for 40 and 20 over a dense radial field (~60), but removed them when the vertical dipoles prevailed. The Inv-L worked all bands 10-160, with varying results depending on the other antennas and signal direction/time of day. I fed it with both coax plus RF chokes at both ends of the run, and twin-lead over the few years it was up. It was a full size vert on 80 due to a second wire parallel to the 160 L fed at the same point. The twin-lead fed Inv-V did the same for all bands, and had good gain on 10-40 off the ends. The Inv-L usually beat the Inv-V at the same height (~80') on 80-160. In my experience an Inv-L for 160 would be a good choice if one could only have one wire. Tuning is critical for multi-band ops. During this experiment I also had a 2-el horizontal loop for 80 at 55', which was excellent for NVIS and out to ~2500 miles from KL7, and a 1000' horizontal loop at 50-80', which was not worth the effort to build. Today, only the 80 loop and F-12 beam remain at that location. 73, Gary NL7Y ___ Topband reflector - topband@contesting.com
Topband: Fwd: Fw: GAP VERTICAL QUESTION
One thing to consider (a non-Gap subject as this thread is drifting, sorry) is to make your 80M loop into a 160 dipole when desired if a 160 aerial isn't available. It can be done mechanically by separating the loop half-way around (via a relay, or connecting drooping ends from the ground...done that once), or electrically by inserting a wound coil at that point (not sure of the coil specs, however. Just read about it being done. Might be another Amateur Urban Legend). A side note. The tall GAP Voyager did serve some useful purpose during the forest fire that burned my tree supports out in the woods. I disassembled it before the fire arrived and used the aluminum tubing to hold several common yard sprinklers off the ground and staked in a perimeter around the dwellings. The sprinklers and water pumped from a nearby lake saved the structures. The Titan I returned to town, but was discarded when I put up the tower and SteppIR beam. 73, Gary NL7Y Personally, I use an 80 M loop - I like it especially for stateside contest like Sweep or FD. Nice solid signal on 40M and 80M. It does much better than the Titan. But the Titan is much less maintenance and I don't have to put it up and rebuild it each year. With two hurricanes, no guying and no maintenance work at all, the antenna stays up, good SWR and I can make the occasional contact. Will I ever be the big dog - nope. I had a much better station in the mid-west, but we all make compromises,. ___ Topband reflector - topband@contesting.com
Re: Topband: Fwd: Re: Fw: Outing the Scofflaws - Getting Old
I don't use a PC in the shack out of choice. Spots don't exist. I tune around and work what I hear. W3LPL helps those that use that service. 73, Gary NL7Y ___ Topband reflector - topband@contesting.com
Re: Topband: HFTA, Radio Arcala, general comments
As I recall they never blew up the receiver here, unlike TF4M, GM3POI, and others in that direction from KL7 who were consistently available during times of low absorption over the N Pole. Then again, who knows what antenna array they were using or the ERP when heard. I'd still like to know their A/B results as there's something to be learned from all that hard work. 73, Gary NL7Y How strong of a signal can that enormous Yagi radiate into the USA on 160? I have never heard them. 73, Mike www.w0btu.com ___ Topband reflector - topband@contesting.com
Re: Topband: Monopole Elev Pattern w.r.t. Earth Conductivity
My 160 aerial next season may be a top loaded vert that can be laid over from the base. After fiddling with an L at 64N latitude, I'm curious about which portion of the L is best as propagation and angles (?) vary. Our ionospheric world is different. We can hear the Aurora and it's effects...from quiet to loud background QRN as conditions change during absorption events. It's audible on vertically firing horizontal loops especially with an on-ground reflector. I'd like to see if altering the vert's angle has any effect. It may not, but ??? 73, Gary NL7Y Guys, I am probably completely off the wall here. But given all the talk about a 300 foot vertical not working well on 160 and a very high dipole not working well on 160 leads me to a very unscientific conclusion or a possible real hypothesis.. That super low angle radiation is NOT a good thing for 160. SNIP Mike AB7ZU ___ Topband reflector - topband@contesting.com
Re: Topband: Soldering in the wild!
Soldering in wild Alaska/KL7. Two hands and a mouth. Wire supported in one hand, butane/propane torch in other, solder roll in the mouth (don't tongue the contents) with a long lead of solder feeding the joint. Face downwind to avoid burns. After suffering numerous heating related failures at the soldered joints during subsequent wind events, I now use these heat shrink crimp connectors: http://www.youtube.com/watch?v=jCRsx38WRw8 Leaves the hands free to swat mosquitoes, or mouth available to yell at approaching bears. 73, Gary NL7Y ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: THE ITINERANT 160 METER ANTENNA PROJECT
Why an L versus a T, with the T's arms over the radials depending upon wind direction? Just curious. Not questioning the design. KH8, some days we can almost see it from Alaska. GL and keep dreaming, we'll be looking for a contact. 73, Gary NL7Y ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Stew Perry Log Submittal
I actually did bang away at the key off and on for a couple last eve after midnight...nothing heard or worked. Receiving loop, and flat-top 80 M dipole at 70' with the twin-lead shorted and fed against elevated radials. Perpetual daylight in Interior Alaska may have had some effect. That, and no relatively close Rat ops or locals led to a slow eve. It's been 47 years since I've seen stars during a June summer's eve. That's KL7 for you at BP64. 73, Gary NL7Y Naw - nothing that sinister. I was going to get to this before the contest - but life events sort of overtook my free time and I didn't get to it. QRX a few days (which is why you didn't hear K7RAT on this time). We'll get it fixed. Tree ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Small loop Performance
Well, my Wellbrook might work as well yours, as I too have worked CE/K7CA with mine on 160 from the Black Hole of KL7. More than once as well. For me the magic isn't directional gain, it's the improved S/N and the ability to null local single point QRN. If I were able to extend a Beverage or three I'd do so. Unfortunately the city snow plows would allow none of that. Gary NL7Y However, in terms of pulling in DX, again, one loop is generally as good as another. Using the loop design I wrote up in the National Contest Journal, I've heard DX such as CE/K7CA on my loop, but other people have built the same loop design and not gotten such good results. Assuming they properly duplicated the design, it is just one of those Your Results May Vary situations. It would be very unlikely that the Wellbrook or some other loop would produce significantly different results. Rick N6RK ___ UR RST IS ... ... ..9 QSB QSB - hw? BK ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Topband: Fwd: Wellbrook receive loop performance
I've had a Wellbrook 1530 loop up for a few years on a rotator at about 20' It excels on a small city lot in nulling local noise sources off its sides. Far better than the MFJ and ANC noise nuller boxes and sense antennas I have used on 80 and 160. Legal limit 75' away on 160 hasn't killed it yet. I do have the rotator control cable and coax common-mode suppressed with ferrite cores at both ends. I get no RF feed back in the shack via the device. If the desired signal and noise sources coincide (for example there's a powerline 60' away between me and EU), it still provides a better S/N than my Inv-L in that direction. 73, Gary NL7Y ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Radials help (Mark van Wijk)
Public domain edition also available in downloadable Format: http://snulbug.mtview.ca.us/books/RadioAntennaEngineering/ 73 Gary NL7Y Herb, Radio Antenna Engineering, published in 1952. It was written by Edmund Laport. It is available from Lulu Enterprises 3101 Hillsborough Street Raleigh, NC 27607 73 Price W0RI ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Solar Activity Topband
Pretty quiet up here in KL7 last eve…only sigs were between the Auroral zones, not across. Mainly 40M. Will try 160 test again tonight. Poor propagation culprit: http://helios.swpc.noaa.gov/ovation/# 73, Gary NL7Y '591 ___ UR RST IS ... ... ..9 QSB QSB - hw? BK ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
Re: Topband: Small loop in Inv L to secure wire to tower
The insulator loop will work. Anything that amounts to a strain relief will work. What I do in a very similar situation is tie some nylon cord (in a series of about 10 tight half hitches) around my insulated vert wire, than tie the cord to the feed point balun box mounted on the supporting tree. The cord grips the wire's covering. I make the cord short enough so that all the stress is on the cord, and the wire simply makes a small half loop below the wrapped cord to the feed. I trim the resonant frequency by shortening or lengthening the vert wire via one or more fold-backs of excess in the wire taped tightly to the main vertical run. I'm using seven tuned elevated radials on a small lot, and the resonant freq shifts as the ground and trees freeze and thaw in Alaska. Gary NL7Y I am putting up my Inv-L , one thing I fear is that if the wire breaks at the feed point I will lose the wire as if goes thru the pulley at the top of the tower. Is it ok to have a small loop about 3-4 ft above the feed point around an insulator , so I can secure it to the to the tower so that in the event of a break at the feed point I don't lose the antenna. thanks Dan N8DCJ ___ UR RST IS ... ... ..9 QSB QSB - hw? BK
