Author: Michael Tope" <W4EF@dellroy.com (Michael Tope)
Date: Mon, 12 Feb 2001 03:11:58 -0800
Hi Yuri, Modeling has evolved to the point where it is an extremely useful tool for antenna design. It was developed because physical iterations and measurements on real antennas are very time consum
Author: Michael Tope" <W4EF@dellroy.com (Michael Tope)
Date: Mon, 8 Jan 2001 23:04:32 -0800
Tom/Chris, Do either of your Telerex 40 meter beams have solid rod stainless steel element tips? Dean Scarborough, KS8S used to have two 40M329 stacked at 90' and 180'. As I recall, he had a problem
Author: Michael Tope" <W4EF@dellroy.com (Michael Tope)
Date: Tue, 9 Jan 2001 08:57:18 -0800
Hey Bill, I don't know why they chose to use solid tips on that antenna. I still remember being surprised to learn that when we got the antenna off the tower, as I had never seen that sort of design
Author: Michael Tope" <W4EF@dellroy.com (Michael Tope)
Date: Tue, 9 Jan 2001 09:08:57 -0800
Hi Chris, Don't lose heart over my comments. Even if the 40M329 has some weakpoints, I suspect that between some computer optimization work with the dimensions and some mechanical modifications to th
Author: Michael Tope" <W4EF@dellroy.com (Michael Tope)
Date: Wed, 10 Jan 2001 03:22:28 -0800
I want to love my 80 meter dipole at 27 feet, but it doesn't seem to get the message, especially on 80 meter longpath. As they say, you can't fool mother nature. Perhaps I should have qualified my co
Author: Michael Tope" <W4EF@dellroy.com (Michael Tope)
Date: Wed, 10 Jan 2001 14:19:23 -0800
My friend applied for a conditional use permit for his crank-up tower about a year ago. As part of the permiting process his neighbors were notified and a publice hearing was held. One of the letters
Author: Michael Tope" <W4EF@dellroy.com (Michael Tope)
Date: Thu, 11 Jan 2001 19:58:18 -0800
Heres one for all you radial efficiandos. I am involved with a site (workplace club station) where the antennas sit near the edge of a 400 foot mesa. The mesa drops off in the direction of our longpa
Author: Michael Tope" <W4EF@dellroy.com (Michael Tope)
Date: Fri, 12 Jan 2001 03:31:41 -0800
Hey Tom, Yes, I should have mentioned the station is just Northeast of the LA basin in the foothills of the mountains. There is another set of hills about 1 or 2 miles south of the Mesa (approximatel
Author: Michael Tope" <W4EF@dellroy.com (Michael Tope)
Date: Sun, 14 Jan 2001 18:54:01 -0800
See my comments below: Mike, W4EF............... As long as a fairly tight sleeve or thrust bearing are used, the forces on the rotator even when its mounted close to the top should be almost purely
Author: Michael Tope" <W4EF@dellroy.com (Michael Tope)
Date: Tue, 16 Jan 2001 05:05:14 -0800
There was an article in QST a while back (its been several years) on house bracketing a tower which was coauthored by N1CQ, a structural engineer. As I recall the authors went to a great deal of trou
Author: Michael Tope" <W4EF@dellroy.com (Michael Tope)
Date: Fri, 19 Jan 2001 00:11:17 -0800
This seems to be a common problem with R25. Like the T2X, the M^2 Orion OR-2800 is just a tad too big to fit inside the cross braces. Has anyone investigated making spacers tubes to go between sectio
Author: Michael Tope" <W4EF@dellroy.com (Michael Tope)
Date: Fri, 19 Jan 2001 06:13:58 -0800
Hi Dick, I have been scolded for this before, yet people don't seem to hesitate for a minute to stack big arrays on 2" chrome moly masts which will yield before R25 does. Anyway, in my case the R25 i
Author: Michael Tope" <W4EF@dellroy.com (Michael Tope)
Date: Fri, 19 Jan 2001 06:38:45 -0800
Ford, Unless your system noise is limited by your receivers internal thermal noise floor (usually not the case on 160 meters), the mismatch loss caused by the 220 ohm termination will probably be inc
Author: Michael Tope" <W4EF@dellroy.com (Michael Tope)
Date: Mon, 22 Jan 2001 00:22:21 -0800
FWIW, a friend of mine in Thousand Oaks, Ca bought a Tri-Ex crank-up from First Call. Despite long delays, lots of phone calls to Tri-Ex and First Call (my friend jokes that First Calls motto should
Author: Michael Tope" <W4EF@dellroy.com (Michael Tope)
Date: Tue, 23 Jan 2001 05:02:36 -0800
Hi Dan, Yes, of course, but I would hate to see the Tri-Ex product get a bad rap because of poor business practices of their dealer, Mr. Kornreich. Also, I thought it important to note that at least
Author: Michael Tope" <W4EF@dellroy.com (Michael Tope)
Date: Tue, 23 Jan 2001 18:10:18 -0800
Ed, What kind of noise dominates your noise floor on 40 meters. Are you limited by power line noise or other man made noise (light dimmers, TV horizontal sweep noise, computer hash), or a you mainly
How much gain do you need, Darfug? If you don't need too much gain (<15dBi), a yagi might be a better choice for 2 meters. 73 de Mike, W4EF............................ if Weather Stations", and lot's
Is KN4T still around, Bill? I seem to remember that he had once been a guest on Wall Street Week with Lewis Ruekeyser (sp?). Doesn't seem like he is active in contesting anymore, however. Mike, W4EF.
Seems like an EIRP scheme would take away incentive to make ones antenna better. Why put up a 4-square to get 5dB of extra TX gain, when you would have to derate your transmitter power by that same a
Yeah and drive by the exchange with your KW mobile during a big selloff :):) Mike, W4EF.................................... -- Original Message -- From: "Courtney B. Duncan" <courtney.b.duncan@jpl.na