Since so much of lightning is pulse related, and I don't have a verifiable analytical device to measure and take that into account, I can't really say that it does or doesn't work and why. However, i
Hi, Does anyone have a source of 75 ohm twinlead, in the USA or overseas. Seems to be much rarer these days. It's just the bill for a colinear matching problem. TIA & 73, Guy K2AV
Just called VGE. They have *72* ohm twinlead, and the conductors are #13. It's transmitting stuff. Thanks for the help. Guy K2AV To: <towertalk@contesting.com> To: <towertalk@contesting.com>
We're up to three different confirmed sources now... Have heard of the lamp cord trick. This will be used on 15 meters, so the dielectric is really important. I used 75 TL some years ago and I rememb
Would note here that Chuck was measuring current key down, which is a different measurement than what ON4UN was making. Even if Chuck's central piece of coax was isolated by 100 db from the coax eith
Personally, in my private cogitation space, where I don't have to prove anything to anybody, I've gotten a good bit disbelieving of the various mental simplifications of ground. Not at all convinced
Hi, Gene. Thanks for the URL. Got out the data for my Trylon and antennas and put stuff in, including the mast. Got basically the same overall figures as by other means. It was interesting to note th
In normal dirt, there's no point to using plywood aside from making the *TOP* neat to see. Underground, concrete on undisturbed earth is best. Some soils are so crumbly that the hole won't keep its s
You are into some interesting stuff. Can of worms... 1) 60 is more the point of diminishing returns for 1/4 wavelength radials. Depending on your ground, 13 radials can be anywhere from just so-so to
I would estimate that the principal loss is in the maximum f/b possible on a given band. However, in a fixed yagi the maximum f/b only occurs at a given frequency and drops off either side. Meaning t
Best kept secret around, but since modeling can be a pain on certain days, noone wants to do ALL the math before bolting in the stacks. Modeling all the stuff around, including booms and guy wires an
The shield has to be modeled as a wire in it's own right. It's in the other element's fields. If you break the shield connection at the relays then it's short, nonresonant and of small effect. Otherw
Faraday shield does not apply to insulated wires (including coax shields) run for extents outside the cage (tower) as well. Models of my entire tower (all the members) show current on the interior. S
Interesting general Query...thought I'd forward it along. Please post to other channels. Keep M3MPH on the reply list. out mystery British still abbreviation? pilots,
Seems to be an awful lot of air time trying to kill fleas on the elephant. An earlier post is correct that the tower flexibility necessary to engage guy wires is quite missing on self supporting towe
No, EHS guys are not stretching to give this effect. The guys are not tightened to make them straight, they are tightened to present a certain designed tension on the tower. If you sight down them, y
Taking one's breath away is a measure of psychological effect. Inches is the physical measure and can be seen with a transit on the ground. These are not self-contradictory statements. The movement o
Amen. Without getting your station in the middle of the connection. And if not, all the miscellaneous house wiring and coax will be participating in equalizing local ground charge during a close stri