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1. Topband: Interesting article on LF antennas and propagation (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Thu, 28 Sep 2000 14:39:05 -0400; TopBanders, If you have access to the IEEE journals (perhaps at a technical library), check out the August 2000 issue of the IEEE Antennas and Propagation Magazine where you'll find a fairly technica; /archives//html/Topband/2000-09/msg00167.html (8,195 bytes)
2. Topband: 3W5FM (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Wed, 09 Feb 2000 09:05:25 -0500; Coly had a decent signal here in MA for a short time this morning. I first heard a couple VK's calling him and then I began hearing him on the NW path around 1145Z. Reception on the SW path was too n; /archives//html/Topband/2000-02/msg00078.html (6,821 bytes)
3. Topband: LP JA tonight (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Sat, 01 Jan 2000 18:44:19 -0500; HNY TopBanders! The new millenium got off to a great start with some excellent conditions today. Tonight around 2200Z, JA6BZI was heard on the long path from the SE on 1910 kHz (QSX 1831). Unfortunat; /archives//html/Topband/2000-01/msg00002.html (7,336 bytes)
4. Topband: More LP JA (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Sun, 02 Jan 2000 18:08:37 -0500; For the second consecutive day the long path to JA was open. I heard (but did not work) JA4LXY on 1911.9 around 2200Z tonight via the SE long path. Signals were in for about 5 or 10 minutes at 449. T; /archives//html/Topband/2000-01/msg00006.html (7,084 bytes)
5. Topband: Vertical on tophill loc. ? (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Thu, 06 Jan 2000 17:31:25 -0500; In general, terrain which slopes downhill enhances radiation at very low angles. This is true for both horizontal and vertical antennas. The details depend on the antenna and the features of the terr; /archives//html/Topband/2000-01/msg00031.html (7,798 bytes)
6. Topband: More 3W5FM, Reflector, etc. (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Sat, 08 Jan 2000 12:03:11 -0500; My guess is that signals propagate normally I also have a "gut feeling" this explanation is correct much of the time. I have observed only relatively few 160 m LP openings, so it's hard to generalize; /archives//html/Topband/2000-01/msg00059.html (9,362 bytes)
7. Topband: More 3W5FM, Reflector, etc. (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Sat, 08 Jan 2000 14:53:19 -0500; It's about 330 degrees--almost the same as JA--so a 180 degree reciprocal path really should be SE. However, because VK6 is not too far from antipodal, these LP/SP distinctions are perhaps not so mea; /archives//html/Topband/2000-01/msg00064.html (9,443 bytes)
8. Topband: Band noise level (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Thu, 27 Jan 2000 11:45:19 -0500; The past few weeks I've noticed that the ambient noise level on the band at my QTH in MA seems to be quite high from the W/SW directions in the mornings before sunrise. It's 10 to 20 dB higher than i; /archives//html/Topband/2000-01/msg00225.html (7,253 bytes)
9. Topband: MFJ-1025 troubleshooting help (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Sat, 11 Dec 1999 18:54:13 -0500; I recently acquired a MFJ-1025 noise canceller (not the MFJ-1026) and its operation differs in one area from what is stated in the manual. According to the manual on page 4: "The main antenna input h; /archives//html/Topband/1999-12/msg00096.html (7,338 bytes)
10. Topband: VE1ZZ (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Mon, 13 Dec 1999 10:26:09 -0500; In addition to a great QTH and antennas, Jack has a big LP advantage over the rest of North America in that VE1 sunset is quite a bit earlier than for the rest of us. This gives him much more darknes; /archives//html/Topband/1999-12/msg00105.html (7,844 bytes)
11. Topband: Confusion with Terms (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Mon, 13 Dec 1999 22:28:35 -0500; The term "long path" tends to be used kind of loosely but people are usually referring to something very roughly in the direction of "reverse azimuth". On 160 it's pretty hard for most of us to deter; /archives//html/Topband/1999-12/msg00115.html (7,845 bytes)
12. Topband: Folded Unipole vs Series Fed Vertical (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Wed, 15 Dec 1999 09:54:50 -0500; As I recall, the Lewis, Brown, & Epstein paper did show a small additional gain (something like 1 dB, maybe a bit less) by going to 120 radials but only when those radials were on the order of 0.4 wa; /archives//html/Topband/1999-12/msg00132.html (8,131 bytes)
13. Topband: What was that JA contest this morning? (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Wed, 22 Dec 1999 09:29:56 -0500; It's on 3925 and yes, I've observed it for many years, finding there is indeed a strong correlation to propagation to JA on 160 (and 80). Another great beacon is the BBC relay in Singapore on 3915 kH; /archives//html/Topband/1999-12/msg00259.html (7,808 bytes)
14. Topband: Adding Radials (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Wed, 22 Dec 1999 15:03:50 -0500; Radial layout in the near field has little or no influence on directionality. To see any improvement in a particular direction you would have to add at lot of very long (many wavelength) radials in t; /archives//html/Topband/1999-12/msg00268.html (7,358 bytes)
15. Topband: UA2FF (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Tue, 09 Nov 1999 13:29:09 -0500; Yes, they are indeed using a Spitfire. I received some correspondence earlier this year from Igor UA2FZ about the antenna and he reports that they have had great success with it at RW2F. 73, John W1F; /archives//html/Topband/1999-11/msg00064.html (6,956 bytes)
16. Topband: Elnec model of Inv L (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Tue, 30 Nov 1999 15:04:20 -0500; ELNEC (or any other MININEC derived modeling program) is not capable of accurately calculating gain of antennas with horizontal wires close to ground, including verticals with elevated radials (or co; /archives//html/Topband/1999-11/msg00216.html (7,400 bytes)
17. Topband: losses on beverages (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Sat, 16 Oct 1999 14:02:09 -0400; I have found exactly the same thing with terminated Beverage antennas. I believe this can at least partly be explained by the fact that a mismatch at the receiving end of the Beverage causes a partia; /archives//html/Topband/1999-10/msg00099.html (7,615 bytes)
18. Topband: K1FZ Beverage Transformers (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Wed, 27 Oct 1999 14:08:14 -0400; I've been involved in re-doing the low band antennas at KC1XX the last few months in preparation for the upcoming contest season. I helped install four 2-wire Beverages which use the K1FZ KB-2 feed b; /archives//html/Topband/1999-10/msg00169.html (8,372 bytes)
19. Topband: K1FZ Beverage Transformers (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Thu, 28 Oct 1999 08:04:08 -0400; I would suggest trying a reflection transformer at the end of the Beverage. Connecting one the Beverage wires directly to ground generally results in an impedance mismatch between the "antenna" mode; /archives//html/Topband/1999-10/msg00177.html (8,616 bytes)
20. TopBand: Re: 160 LP (fwd) (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Fri, 05 Feb 1999 13:23:14 -0500; I've personally got thousands of LP QSO's on 40 I also have many LP QSO's on 80 and 40 (not as many on 160 unfortunately!), and in cases where the DX stations have had directional antennas, they have; /archives//html/Topband/1999-02/msg00034.html (8,546 bytes)

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