If my memory has not deteriorated too much, my understanding of a Ufer ground is that it approximates a capacitance in parallel with a resistance. The theory was that the capacitance would absorb the
I think reflections from the tank would wreak havoc with the pattern using omni antennas. 73, Roger -- Remember the USS Liberty (AGTR-5) http://ussliberty.org/ _______________________________________
I agree that this seems to be the simplest solution. If lightning takes out this array, then I'd think about the Yagis mounted around the tower at a lower level. 73, Roger -- Remember the USS Liberty
I did find a site which said that 20 ft of rebar in concrete is capable of absorbing an 8 kiloamp surge. Since the average lightning strike is around 15 Kamps, it's obvious that these mini-Ufers don'
I really need to find Ufers paper on the subject. As I said originally, my understanding is that the capacitance to grounds important to absorb the charge which then leaks off through the concrete. Y
As I stated originally, I read the description of the Ufer ground many years ago and my memory might be a tad faulty! However, I think we are converging on an explanation. I think Jim is correct in t
If your conductors get this hot they're way too small! 73, Roger -- Remember the USS Liberty (AGTR-5) http://ussliberty.org/ _______________________________________________ __________________________
Can someone explain the difference between a CADWELDED joint and one that is properly brazed? The only difference I can see is the means of generating the heat. 73, Roger -- Remember the USS Liberty
Apparently, CAD welding is a true welding process which joins the conductors together using superheated copper. However, I doubt that the increased resistance of a brazed joint would make any differe
I found this while sniffing around: http://www.erico.com/products/HAMMERLOCK.asp I couldn't find any pricing info though. 73, Roger -- Remember the USS Liberty (AGTR-5) http://ussliberty.org/ _______
The B&W antenna is known as a T2FD (tilted, terminated folded dipole). There is a good write-up on W4RNL's site: http://www.cebik.com/wire/t2fd.html 73, Roger Remember the USS Liberty (AGTR-5) http:/
I had an Aluminum mast through a Rohn 25AG top section supporting a Mosely Pro-67 for a few years. When I took the tower down to move to a new QTH, there was noticeable scoring of the mast where it r
Several years ago when I had access to a network analyzer, I was tuning up a set of cavities for the local 2m repeater. I couldn't get one of the cans to tune properly and finally wound up replacing
Those that use cheap, painted earth anchors from the local hardware store or farm supply should ensure that they erect the tower far enough from their house so that when the anchor fails it will not
I don't think this is true. My old memory says the length is 180 deg. 73, Roger -- Remember the USS Liberty (AGTR-5) http://ussliberty.org/ _______________________________________________ ___________
I don't think this is true. My old memory says the length is 180 deg. 73, Roger -- Remember the USS Liberty (AGTR-5) http://ussliberty.org/ There is a diagram in Low Band DXing that shows the phase s
Hi Mike et al.... What you say is absolutely correct. However when one talks about the phase shift through a circuit or transmission line, it is assumed that the same property is used at both ends; i
Hi Dave... I think most of the ground testers use frequencies in the low audio range. Are the results applicable at radio frequencies thousands of times higher or are we fooling ourselves when we mea
I was speaking in generalities which always gets me in trouble! Mr Ufer developed his ground system during WW2 to protect ammunition storage bunkers in the desert southwest. The theory being that, du