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## Re: [TowerTalk] Calibrating antenna direction and using chokes witha bea

 To: "Dan Hearn" , "Mike" Re: [TowerTalk] Calibrating antenna direction and using chokes witha beam "Pete Raymond" Thu, 25 Oct 2012 23:47:08 -0400 mailto:towertalk@contesting.com>
 The Operating Manual has a great chapter called Antenna Orientation, that tells you how to figure when the sun is directly due South at your qth. Then you can use your towers shadow as described below. The math and a chart that is provided in this article is called "True corrections for Various Dates of the Year". If you do not have this manual I would check with the ARRL web page and you might be able to access that section of the manual, I'm not sure if the "Operating Manual" is available there or not. It's all about using the sun. I have used this method many times. Good luck ```73 Pete N4KW ```----- Original Message ----- From: "Dan Hearn" ```To: "Mike" Cc: ; "Rick Kiessig" Sent: Thursday, October 25, 2012 9:46 PM ```Subject: Re: [TowerTalk] Calibrating antenna direction and using chokes witha beam ``` ``````Here is a system which works for me and others in our ham club. Look in the newspaper for the times of sun up and sun down. Calculate the hours and minutes between. Divide this by 2 and that is the time of exact ```noon. At that time, look at the shadow of your tower or a vertical post and the shadow points to true north. Hopefully your newspaper has sunup/sundown ```times as ours does. 73, Dan, N5AR On Thu, Oct 25, 2012 at 5:58 PM, Mike wrote: ```There is going to be a website that will give your declination relative to ```Magnetic North in ZL, I would go with that. In California here finding a strong station and adjusting the beam would be futile as the signal maybe following a crooked path. In California we are pretty much at 18 degrees off Magnetic north, so it would make a difference to make the adjustment for True North. ```You government is sure to have a website, but if not any serious navigation website in ZL will have True north relative to your position. Even my car ```manual shows true north so you can set the car compass. Mike -----Original Message----- From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of Rick Kiessig Sent: Thursday, October 25, 2012 5:04 PM To: towertalk@contesting.com ```Subject: [TowerTalk] Calibrating antenna direction and using chokes with a ```beam I finished building my antenna (UltraBeam UB-50) and installing it on the tower yesterday. Everything went reasonably smoothly. I tried to align the boom with true north before bolting it to the mast, but ```the result seems to be off by at least 10 degrees or so. I'm familiar with ```the techniques for determining true north (although Polaris isn't visible in ZL), but I'm wondering if it's possible to do a more accurate calibration by measuring signal strength from a strong broadcaster with a known location ```and a near-constant signal strength, over a range of azimuths. Then use the ```center azimuth between two equal near-nulls on either side of the peak as ```the calibration point. If this is viable, any suggestions for good station ```to use as a target? Does frequency matter? What's the Best Practice with regard to using common mode chokes on the feedline coming from a beam? I grounded the shield at the tower and again outside the shack, with a lightning arrestor as well at the latter. ```Can't say I'm too happy with the way my rotator loop came out. I wrapped it ```around the mast on top of the thrust bearing, but the TB has some bolts that stick out. Hopefully they won't grab or scrape the coax too much. I also have a UHF connector on one segment of LMR-600 that didn't seem to go ```onto a barrel connector as well as it should have. They are odd connectors ```that have a very snug rotating collar, rather than the kind I'm used to that have a little up-and-down give in the direction of the cable. The center pin went in roughly 4 or 5 mm, but the collar hung up after only about two ```turns. It's very snug (too snug), so I think the threads may have crossed. ```I'm reluctant to take it apart now, though, since if the threads are crossed, I may never get it together again, and it's a long segment of LMR-600, which I don't have the tools or skills to replace connectors myself. TDR on the line looks OK, and I did some TX tests at low, medium and high power, and didn't see any problems. I imagine I'm just asking for trouble if I don't fix it, though, right? 73, Rick ZL2HAM _______________________________________________ _______________________________________________ TowerTalk mailing list TowerTalk@contesting.com http://lists.contesting.com/mailman/listinfo/towertalk ----- No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.2221 / Virus Database: 2441/5353 - Release Date: 10/25/12 _______________________________________________ _______________________________________________ TowerTalk mailing list TowerTalk@contesting.com http://lists.contesting.com/mailman/listinfo/towertalk `````` -- Dan Hearn N5AR _______________________________________________ _______________________________________________ TowerTalk mailing list TowerTalk@contesting.com ```http://lists.contesting.com/mailman/listinfo/towertalk ``` _______________________________________________ _______________________________________________ TowerTalk mailing list TowerTalk@contesting.com http://lists.contesting.com/mailman/listinfo/towertalk ```
 Current Thread [TowerTalk] Calibrating antenna direction and using chokes with a beam, Rick Kiessig Re: [TowerTalk] Calibrating antenna direction and using chokes with a beam, Mike Re: [TowerTalk] Calibrating antenna direction and using chokes with a beam, Dan Hearn Re: [TowerTalk] Calibrating antenna direction and using chokes with a beam, K8RI Re: [TowerTalk] Calibrating antenna direction and using chokes witha beam, Pete Raymond <= Re: [TowerTalk] Calibrating antenna direction and using chokes with abeam, Gene Fuller Re: [TowerTalk] Calibrating antenna direction and using chokes with a beam, Ron W8RJL