I agree. #31 would be my first choice below 5 MHz. Jim K9YC _______________________________________________ _______________________________________________ TowerTalk mailing list TowerTalk@contesting
The resistivity simply doesn't matter. There's a lot of "beef" there to provide VERY low resistance. What matters a LOT more is corrosion. That's why DXE selected stainless for the plate and the hard
They are simply two good ways of doing the same thing, although your method could be improved (very slightly) by making multiple connections between the radial ring and the coax. Ya pays ur money and
On the contrary. It makes exactly the point that I would have made had I taken the time to respond, and in words I would have been pleased at having put together. The only significant characteristics
Yep! An example of that was the wrought iron fence that ran around the front yard at my urban Chicago QTH. Adding it to my improvised top-loaded vertical improved my signal a lot -- probably 10 dB. J
Hi Guys, I'm traveling to these cities in a few weeks, and would like to be able to use my Garmin GPS there. A CD for EU costs nearly $275, which is nearly as much as I paid for the GPS (and almost h
-- be hams On the contrary. You have put your interpretation onto the QST author's statement, and words in his mouth. He did not say "that any number of radials, even a few is okay." YOU said that. H
That's my only criticism as well. And it could have been handled quite well in a paragraph or two. Jim K9YC _______________________________________________ ___________________________________________
There was considerable research on the topic in the early days of broadcasting. An engineer named George Brown (no relation) was a leader in this work. Standards and FCC Rules for AM broadcasting wer
Near the beginning of this thread, I observed that the ARRL Antenna Book includes an EXCELLENT discussion of radial systems for antennas, and addresses the question of how much, how good, and why in
Yes. It is VERY well known (that is, long ago proven science) that radials affect the EFFICIENCY of a vertical, while the ground in the far field determines the vertical radiation pattern, especially
My limited experience at my new QTH on 160 (one season) with both a horizontal dipole at 90 ft and a 70 ft top-loaded vertical with 40 70-ft radials is that the vertical is at least 10 dB better with
There's a discussion of this in Appendix 5 of the RFI tutorial that is on my website. http://audiosystemsgroup.com/RFI-Ham.pdf 73, Jim K9YC _______________________________________________ ___________
I'll take that a step further. The safest approach is a whole house unit at the service entrance taking care of what comes in on the feed to the building, including provisions for telephone lines, CA
The potential problem is that if you add radials to only one tower, the DIFFERENCE between the two towers will screw up the pattern on 80 by unbalancing that array. If it were my antenna system, I wo
I disagree. Matching is trivial. My concern is the pattern. I would expect to see little change in the lobes, but significant degradation of the nulls. Maybe you don't care about the nulls, but I've
Nulls are created by cancellation of signals that very nearly equal and very nearly 180 degrees out of phase at the point of observation. For the null to be 20 dB deep, the field strength of the two
Try AV Cable, near Chicago. www.avcable.com They are primarily am audio/video cable vendor, but very nice people and they are a Belden distributor. I've never bought coax from them, so have no idea a
I think you may misunderstand the relative conductivities of concrete and soil. Both vary widely, depending on their chemistry. Some concrete mixes are good enough insulators to be used as insulators
There's a technical piece in one of the later ARRL Antenna Anthologies showing that ladder line can get quite lossy when the insulation gets wet, even at frequencies as low as 160 meters. So I would