On Thu, 26 Nov 2009 20:28:51 -0800 (PST), "
wrote:
http://www.cammenga.com/cammenga-pro...php?category=1
The phosphorus version is good enough. I "juice it" with a flashlight
since I'm not working SWAT or special ops. ;-) You can pay extra for
tritium, but it wears out. You shouldn't buy one used for that reason.
The phosphorus version is under $40 and it will last a lifetime, or
until it is lost or stolen.
Yech. I do some TV antenna alignments and the usual point to point
wireless. I don't bother with a compass because they're not accurate
enough. What works best is a road map, a plywood board, and some
nails. Mark your position on the map with a nail, push pin, or pin.
Mark the position of a distant mountain, building, or landmark on the
map. Eyeball the line between the two nails to the distant mountain,
building or landmark. All maps have true north marked on them. The
direction of the map arrow is true north. I can usually locate true
north to within +/- 2 degrees depending on the size of the map and the
distance to the marker. Using multiple distant points improves the
accuracy.
If you're into astronomy, sighting the north star also works well.
Also, using a computer sky chart/map to locate easy to find stars.
One I establish true north, I like to mark it on the road, sidewalk,
or deck with a line or arrow. I have a brass marker arrow nailed to
my deck.
I have a GPS with a compass in it, but you have to remember to
calibrate them. Really annoying.
Calibrate? You have to be moving in order for it to work. Then, it
will only tell you the direction that you're moving. If you only go a
short distance, it's not going to be very accurate.
Next up of course is that damn magnetic correction.
I don't do no stinkin magnetic correction cause I don't use no stinkin
magnetic or fluxgate compass.
Incidentally, I have a really handy item for watching expensive birds.
I made a panorama (stitched) photo of the view from my rooftop at
home, at the office, and at my favorite astronomy meeting places. I
then marked the azimuths every 10 degrees on the JPG. Although
difficult to see the remote hilltops at night, I now have the azimuth
of anything in the sky or between me and the surrounding hills.
--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060
http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558