Dear all, In preparation of this coming WW big contest, I plan to install wire antenna on a roof top of a 33rd storey building (about 110metres above the ground) for operating on the 160M, 80M and 40
Many years ago, at the start of my sophomore year in college, a classmate and I decided to operate CW Sweepstakes from my room in a 5-story dormitory. The dormitory footprint was a long, skinny rect
Nuradi, how about halfwave sloping dipoles hung digonally from the top of the building? Some 30 years ago at YU1EXY we had contest shack at top of 60m tall building with student's dormitory. In spite
I agree with Mirko...sloping dipoles is the best choice for Nuradi location...THE LOW BAND DXING book is very clear. If SEA WATER is close it is better. 73....Douglas, CO8DM "No creo que haya alguna
Hmmm! Let's remind ourselves of Nuradi's situation. The roof is 110m high, 45m x 33 m. Corner to corner is less than a wavelength on 80M, more than a wavelength on 40M, but the distance to a corner f
Jim Im not sure youre missing anything from a theoretical standpoint. Some comments from a practical standpoint, however: 1. In my dormitory roof example, our objective was to work W/VE most of whom
Hmmm! Let's remind ourselves of Nuradi's situation. The roof is 110m high, 45m x 33 m. Corner to corner is less than a wavelength on 80M, more than a wavelength on 40M, but the distance to a corner f
I'm still laughing !! Ollie did try a safety idea when he tied a rope around his waist in case he fell. Who would have thought the brick chimney would come crashing down ? HIHIHI thanks Frank ! Bob K
It might be fun to drive around Culver City for a while and find some of those old buildings. The houses are a lot closer together now, but most of the originals are probably still there. 'JK I hope
Hi Bud, Thanks for comments. I used sea water in the model to correspond to your copper plate example. I also tried other less conductive mediums for the roof as a sanity check. What changes is the s
Tom, I agree with this post on all counts. What's actually there can be difficult to predict or even know, so anything that can be installed reasonably easily is worth a try. Yes, an end-fed wire loa
Hallo Frank,W3LPL It's very funny 'old' film...hi hi Thanks for remind me...just dreaming how to break the 160m-S9 noise as what has happened so far in my House and office using an 1/2 lambda inv.V w
There is a rather stern W7EL caution in the EZNEC doc about using two ground media. He particularly nixes using the inner media as sea water to mimic a high conductive surface. --(EZNEC doc)-- "Using
Actually, what he says is not use the high level media to model a RADIAL system. While playing with this model, I changed the characteristics of the higher level media to have far less conductivity.
Hi Jim, I must respectfully disagree. And warn any reader that using NEC ground media to simulate a conductive roof is a very troubled procedure with significant issues. Using the first media to simu
Ah, perfection. Sadly, EZNEC does not provide that set of options. If I could build that model, I would. But I can't. I will take this first approximation, understanding its limitations. Brown's 99th
No. You'd be missing the essential point which has to do with the "shape" of the tool and whether it was remotely suited to the problem. The best estimate of NEC applied to this problem, even with a
Guy and jim, No, I'm not missing anything -- did you miss my words "first approximation" in my description of the model? That model was a feasibility study, not intended or accepted (by me, at least)
Okay guys - when email starts getting this specific and personal - the rest of the list is really not interested in it. Please take this debate off the list. Thanks. Tree _________________ Topband Re