65
Appendix F
Magnetic Declination of the observing area
by referring to the Magnetic Declination Map
(Fig O). Locate this value on the compass
face for future reference.
NOTE:
East Magnetic Declination means Magnetic North
is to the right (East) of the True North position and West
Magnetic Declination means Magnetic North is left (West)
of the True North position. For example,
Fig. N
shows the
correct setting for 13.5° East Declination which covers
Irvine, CA. The compass scale markings range from 0 to 360
degrees azimuth so for East Magnetic Declinations add the
East Magnetic Declination value from 0 to obtain the correct
reference mark on the compass face.
b. While holding the compass, rotate it so the
red compass arrow points in the direction of
Magnetic North. The arrow should be directly
over the "N" marking on the compass face.
c. Now place the compass onto the fl at base
of the X-Wedge as shown in Fig M. Verify the
compass is still pointing toward Magnetic
North and the bubble level is properly
centered. If the bubble is not centered, adjust
the tripod legs until centered.
2. Finding True North:
The magnetic compass is now ready for use.
Follow these simple steps for a quick and
easy azimuth alignment.
a. Slightly loosen the three 5/16" hex screws
in the wedge fl oor to allow for rotation of the
X-Wedge.
b. Using the Azimuth Control Knob (Fig C,
6), manually adjust the X-wedge around the
threaded rod (without moving the compass)
until the red compass arrow points toward
the observing sites Magnetic Declination
found in step 1.
c. Tighten the t-handle tension knob, locking
the X-Wedge into place.
d. Retighten the 5/16" hex screws on the
wedge fl oor. Do not over tighten.
The tripod and X-Wedge are now pointed directly toward
celestial north, without ever having seen the North Star.
Figure N.
Compass bearing adjusted for Irvine, CA's
magnetic declination.
Figure M.
Compass level placed on the X-Wedge.
