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Total 950 documents matching your query.

1. [TowerTalk] [Fwd: Re: [RFI] Haolgens AND . . .] (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Mon, 20 Nov 2006 14:00:06 -0700
Hi, Jim. I sometimes feel the same way but it really doesn't work that way. People shop at Walmart and Home Depot because they have the lowest prices for products that meet the needs of the majority
/archives//html/Towertalk/2006-11/msg00432.html (8,134 bytes)

2. Re: [TowerTalk] Where does the element go? (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Thu, 23 Nov 2006 21:17:47 -0700
Ted, that is only correct if and while the element is perfectly horizontal above the boom and perfectly centered on it. As soon as the element tips away from horizontal, the center of gravity of the
/archives//html/Towertalk/2006-11/msg00639.html (10,939 bytes)

3. Re: [TowerTalk] interaction problem... (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Sun, 26 Nov 2006 11:35:45 -0700
Maybe I'm missing something, but I don't see anything all that strange with your results. The WARC dipole, for receiving purposes, might as well be a normal 10m dipole. Your stack of C31's at 121, 81
/archives//html/Towertalk/2006-11/msg00690.html (11,676 bytes)

4. Re: [TowerTalk] interaction problem... (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Sun, 26 Nov 2006 12:29:09 -0700
Hi, Gary. OK ... I think I understand better now. If the F/B of the stack is that low, then something must indeed be amiss, and having the SWR vary that much as you turn it would probably concern me
/archives//html/Towertalk/2006-11/msg00700.html (8,956 bytes)

5. Re: [TowerTalk] are small loops in beverages bad? (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Tue, 28 Nov 2006 09:20:24 -0700
Hi, Tonno. I'm not an expert but I doubt it would have any measurable effect. It's easier, though, to simply run the wire under each support and use separate pieces of wire to tie the beverage wire t
/archives//html/Towertalk/2006-11/msg00788.html (9,083 bytes)

6. Re: [TowerTalk] Plumbing a Tower (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Tue, 28 Nov 2006 09:54:32 -0700
Hi, Dale. I don't have a tower up yet (planning one for this coming spring), but I would definitely vote for the laser. My wife and I have been building our own 4500 sq ft home for the last four year
/archives//html/Towertalk/2006-11/msg00793.html (10,042 bytes)

7. Re: [TowerTalk] stacking monobanders (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Tue, 28 Nov 2006 13:45:29 -0700
EZNEC doesn't tell the whole story. VOACAP says the optimum takeoff angle on 40m for crossing roughly half the U.S. (I used from my Arizona QTH to Chicago), such as for Sweepstakes, is about 20 degre
/archives//html/Towertalk/2006-11/msg00805.html (10,837 bytes)

8. Re: [TowerTalk] stacking monobanders (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Tue, 28 Nov 2006 14:02:32 -0700
I disagree with your disagreement ... hi. Per my earlier message, there is 2db difference for a 2 element 40m yagi at 60 feet versus 45 feet. That's about the same as the difference between a 2 eleme
/archives//html/Towertalk/2006-11/msg00807.html (10,014 bytes)

9. Re: [TowerTalk] stacking monobanders (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Tue, 28 Nov 2006 15:33:46 -0700
Doug, Anecdotal results from anywhere are irrelevant ... that was my point. I don't trust software analyses implicitly, but I trust them more than opinions that aren't backed by direct comparison of
/archives//html/Towertalk/2006-11/msg00811.html (10,077 bytes)

10. Re: [TowerTalk] stacking monobanders (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Tue, 28 Nov 2006 23:00:51 -0700
Hi, Rick. Those are interesting comments, so I modeled it up with EZNEC with approximately resonant antennas to see what it looked like. Your message says "inverted vee's" (plural), so I'm making the
/archives//html/Towertalk/2006-11/msg00825.html (12,496 bytes)

11. Re: [TowerTalk] stacking monobanders (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Wed, 29 Nov 2006 09:30:06 -0700
Your are absolutely correct. I didn't try to include that in my quick model because I was only trying to show that parasitic coupling can affect what Rick observed for the three antennas fed separate
/archives//html/Towertalk/2006-11/msg00853.html (16,390 bytes)

12. Re: [TowerTalk] stacking monobanders (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Wed, 29 Nov 2006 17:29:23 -0700
I said "imply"because" I didn't really know if Rick's Inverted-V's were resonant or not, and I was referring to his situation. I can guarantee that EZNEC will show currents being induced in the other
/archives//html/Towertalk/2006-11/msg00872.html (16,244 bytes)

13. Re: [TowerTalk] stacking monobanders (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Wed, 29 Nov 2006 17:59:37 -0700
Hi, Rick. I think K4SAV was referring to me and the model I ran when he talked about overlooking the possible feedline impact ... I don't think he was being critical of you. But for sure, if you had
/archives//html/Towertalk/2006-11/msg00876.html (13,678 bytes)

14. Re: [TowerTalk] 160m inverted l (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Sat, 09 Dec 2006 17:54:10 -0700
Where are you measuring the SWR? If you are measuring it at the end of an arbitrary length of coax you will get all sorts of bad results, including the possibility of seeing an inductive reactance fo
/archives//html/Towertalk/2006-12/msg00242.html (9,633 bytes)

15. Re: [TowerTalk] QRN during the rain (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Mon, 11 Dec 2006 14:08:03 -0700
That's a pretty common experience and it is usually caused by dirty insulators on the lines. Hydrocarbon pollution comes from the air ... static electricity from the wind causes dust to stick ... and
/archives//html/Towertalk/2006-12/msg00341.html (8,211 bytes)

16. [TowerTalk] CoaxSeal vs ? (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Wed, 13 Dec 2006 12:21:46 -0700
I've seen references to both butyl tape and silicone tape for sealing coax connectors. Both appear to be more or less permanently self-fusing. Is one material better than the other? I stumbled across
/archives//html/Towertalk/2006-12/msg00439.html (6,923 bytes)

17. [TowerTalk] Concentric Masts (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Wed, 20 Dec 2006 21:15:24 -0700
I'm going to be limited to one freestanding tower at this QTH, but I'd like to be able to operate two stations simultaneously (with appropriate filters) for when friends visit. I expect to put a 40m
/archives//html/Towertalk/2006-12/msg00777.html (7,736 bytes)

18. Re: [TowerTalk] Bird intelligence (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Wed, 03 Jan 2007 10:20:06 -0700
My guess is that if you asked K8RI to walk and one of your barn swallows to fly to a neutral spot previously unknown to either of them, K8RI would get there first ... Dave AB7E -- Subvert the dominan
/archives//html/Towertalk/2007-01/msg00036.html (9,188 bytes)

19. Re: [TowerTalk] Coax Connectors (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Thu, 04 Jan 2007 11:57:30 -0700
My apologies if someone else has recently posted this link, but VE7BZ has put together a quite excellent tutorial on using crimp connectors, complete with lots of pictures. http://www.bcdxc.org/pl259
/archives//html/Towertalk/2007-01/msg00111.html (8,741 bytes)

20. Re: [TowerTalk] Equality (score: 1)
Author: David Gilbert <xdavid@cis-broadband.com>
Date: Fri, 05 Jan 2007 09:01:56 -0700
No, it doesn't. Equality and sufficiency are two entirely different things. Dave AB7E Wouldn't the basic symmetry law of algebra (equality) apply here? If a=b then b=a. Note again that I did NOT say
/archives//html/Towertalk/2007-01/msg00161.html (7,709 bytes)


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