I'd also go for a compass if you want magnetic north, but then I have a good one, a "medium landing compass". Mine dates from WWII but they are still made http://www.sirs.co.uk/ground/landing_compasses/patt2/landing_resource These are used to align the standbay and remote reading compasses on aircraft. Good to half a degree. If you need better ther is the Watts Datum Compass. Robert G8RPI. From: Chris Albertson <[email protected]> To: Discussion of precise time and frequency measurement <[email protected]> Sent: Thursday, 21 November 2013, 23:28 Subject: Re: [time-nuts] Crude Survey Technique
On Thu, Nov 21, 2013 at 11:11 AM, Don Latham <[email protected]> wrote: > Lord no, John. No red wagon is needed. Use a pole and the equation of > time, and a good watch or clock. At local noon, a shadow will be a n-s > line. How accurate do you need to be? The above requires a very tall pole to case a 300 foot long shadow. Then you have to be quick to measure because the Earth turns at .25 degrees per minute. If you need a very tall pole that is 100% vertical then hang a weighted rope from a tall support. Then go to the other end and watch the seconds tick down. A GOOD magnetic compass can do this job too. Easier then finding s 1,000 food tall pole. The better compasses have some kind of optical aid for sighting a line. -- Chris Albertson Redondo Beach, California _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
