Joseph, Check out this page: http://www.thecompassstore.com/decvar.html# There's a link on that page to plug in your Zip code and figure declination, or you can use the handy map on the main page. For Austin, the magic number is 4 degrees.
If I recall correctly (it's been a few years), I set the rotor control box to North, went up on the roof and rotated the *mast* until the ants pointed to magnetic north (using a compass). Note that the compass will read inaccurately if held near a metal mast. Then I rotated the mast a bit more so the ants were pointing about 4 degrees *West of magnetic North*. That's the way I remember doing it. Bill N5AB On Aug 12, 2009, at 10:28 AM, Joseph Armbruster wrote: > Hey everyone at the amtat-bb! > > I spent a good portion of the day sick in bed yesterday and only > naturally > got to thinking about quite a few things. I figured i'd pop on > here and > start asking questions. Here's some background information on my sat > experience; my rig consists of a TH-F6A (handheld, not full-duplex) > and an > arrow antenna. I have been successfull at manually trakcing the > ISS and > AO-51, but I have been unsuccessful at making a contact. I went > out to > field day (in Oviedo Florida) and was able to check out the rig the > LMARS > club uses. This got me wondering about sat tracking software, the > internals > and what definition of "North" that is used. > > I'm familiar with the IGRF (from my day job as a GIS guy) and was > wondering > if any of these apps use the IGRF for calculating magnetic > declination: > http://www.ngdc.noaa.gov/IAGA/vmod/igrf.html > > I've thought about creating my own rotator and started wondering > about the > configuration used. When you buy a rotator and put it out in the > yard, i'm > guessing you have to orient the base 'correctly'. How is the base > of a > rotator usually aligned? Do you get a compass out and use local > magnetic > north (without compensating for the declination from the IGRF). > > I'm still in learning mode and very new to the world of sat, so if > these are > really dumb questions, my apologies! > > I am open to any reading materials you can suggest on the matter. > > Joseph Armrbuster, KJ4JIO > _______________________________________________ > Sent via [email protected]. Opinions expressed are those of the > author. > Not an AMSAT-NA member? Join now to support the amateur satellite > program! > Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
