Meade LX85 Operating Instructions

For most telescope observers casual polar alignment is all that is needed,
which will not require use of the polar finder. However, for those observers
who need to meet the more demanding requirements of astrophotography, the
polar scope allows the telescope mount to be more precisely aligned with the
celestial poles. The polar scope contains a reticle pattern which is used in
assisting the user in achieving a more accurate polar alignment.
Installing the Polar Scope:
1. Begin by removing the polar axis front and rear covers (see Figure 1).
2. Thread in the Meade LX85 polar scope until firmly seated. The polar
scope is now installed and should remain installed in the mount. When
finished using the polar scope, replace the front and rear covers.
Before the polar scope can be properly used with any precision, it must first be
aligned to the mount's polar axis.
Aligning the Polar Scope to the Polar Axis:
1. Set the telescope mount & tripod up outside in the daytime with the optical
tube, counterweight and counterweight shaft removed.
2. Unlock the DEC axis and rotate it to DEC 90. In this position, the optical
tube (if installed) would be pointing forward. With the DEC axis in this position
and polar scope covers removed, you can now view through the polar scope
at a distant terrestrial target.
3. Look through the polar viewfinder and notice the reticle pattern (see Figure
6). If the reticle is not in focus, rotate the focus ring (Figure 5, #11) until the
reticle pattern is sharp.
4. Adjust the mount and tripod so the polar axis is pointing at a distant terrestrial
object. The further the target, the more accurate the alignment.
5. Placing the reticle center crosshair over the target, unlock the RA and rotate
the RA axis 180 degrees, from one side of the mount to the other (see Figure
3A & 3B). Re-lock the RA axis.
If the polar scope is not aligned with the mount's polar axis, the target will move
off center (see Figure 4A & 4B) and the reticle adjustment screws (see Figure
5, #9) will need to be adjusted.
6. To adjust the polar scope so the target does not move off the reticle
crosshair, slightly loosen the reticle adjustment screw which is opposite
of the movement. Then tighten the adjustment screw on the side closest to
the target. As you loosen one screw, you must tighten an opposite screw to
make the adjustment. Notice that a small turn of each screw will result in a
large movement of the reticle. Only adjust the screws to correct for half the
movement off the crosshair at a time, moving the target approximately halfway
to the center of the reticle.
NOTE: The reticle adjustment screws work in a push-pull motion. When
loosening these screws, never loosen more than 1/8 of a turn at a time. Doing
so could cause the reticle to fall out. When one adjustment screw is loosened,
an adjustment screw on the opposite side should be tightened. Do not over
tighten or you may damage the reticle.
7. Next, unlock the RA axis and rotate this axis 180 degrees, back to the
starting point. Re-lock the RA axis. Repeat steps 4-7 until the target no longer
moves off the reticle crosshair.
8. The polar scope is now properly aligned with the mounts polar axis. You can
now use the polar scope with reasonable accuracy. If you insist on additional
accuracy, follow the below directions on Calibrating the Dials and Indicators.
Calibrating the Dials and Indicators:
There are several additional parts on the mount and polar scope that need to
be calibrated; the RA setting circle(Figure 5, #3), Calendar-dial scale(Figure 5,
#4), and Longitude-offset indicator (Figure 5, #6). All are located adjacent to
the polar scope. For the part locations of these dials, see Figure 5.
Operating Instructions
The Meade LX85 Illuminated Polar Scope
Remove
Remove
Figure 1: Remove polar covers
Figure 3A: Position A
Figure 3B: Position B
1
3A
3B
7
8
(not visible)
10
11
Figure 5: Polar Scope Dials
1. RA setting circle locking screw
2. RA setting circle indicator
3A. RA setting circle -
(Northern hemisphere users)
3B. RA setting circle -
(Southern hemisphere users)
4. Calendar-dial scale
5. Longitude offset scale
6. Longitude-offset scale indicator
1
Figure 2: Rear view of RA axis
Figure 4A: Aligned when object stays
centered at position A & B
Figure 4B: Misaligned when object
moves off center between position A/B
7. Longitude indicator locking set-screw
8. Assembly set screw (not used)
9. Reticle adjustment screws (3)
10. Polar scope
11. Focusing ring
12.Rotary adjustable power switch (on/off)
13.Illuminator (requires two LR41 batteries)
2
4
5
6
9
12
13