KB5NJD's 630 meter page http://njdtechnologies.net/category/630-meters/
630m Class D/E amplifiers, fully built by KB5NJD, for $173 each. Check it out at:
N6LF's 630m Antenna page http://www.antennasbyn6lf.com/
American Radio Relay League http://www.arrl.org/
Call sign lookup http://qrz.com/
Magnetic Declination Calulator http://www.ngdc.noaa.gov/geomagmodels/struts/calcDeclination
Azimuth/Distance Calculator http://transition.fcc.gov/mb/audio/bickel/distance.html
If you are mathematically inclined in Analytic Geometry,
please check out my theorem, a discovery I made while teaching hyperbolic sectors.
I am grateful to WEBS.COM for allowing me to have this free website. It is easy to learn to use.