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| Southern Hemisphere Drift Alignment | Quick Wedge Alignment |
| Installing Bob's Knobs | Collimating The Nextstar 11 GPS |
| Cleaning The Azimuth Track | GPS Battery Location |
| Transporting the Nexstar 11 GPS |
Southern Hemisphere Drift Alignment |
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If you do a search on the web, you will find
plenty of examples of how to do a drift alignment in the Northern
hemisphere. Here is the procedure I follow to perform a drift alignment
in the Southern hemisphere. Only use the Alt and Az knobs on the wedge to make adjustments, do not use the hand
controller during the drift alignment process. Ok, first you
must determine which direction is East / West:
Ok, so which way is North / South / Up / Down? This depends on how many mirrors you have in your scope and if you are using a diagonal. Odd numbers of mirrors (including the diagonal: 3 for SCT, 1 for refractor) use the left diagram. Even number of mirrors (reflector with no diagonal) use the right diagram. The EAST / WEST direction doesn't really matter if they are revered to the below diagrams (when looking through your scope), the NORTH / SOUTH direction will remain unchanged. See the below diagram:
Turning the Alt knob clockwise increases the degrees (raises the wedge plate). Anti-clockwise lowers the plate (looking south). Turning the Az knob clockwise turns the wedge to the east. Anticlockwise turns the wedge west (looking south). HEQ5-PRO / EQ6-PRO Eq Mount Turning the front Alt adjustment lowers the mount (decrease degrees). Back Alt adjustment raises the mount (increase degrees). Right Az knob turns mount west (right). Left Az knob turns mount east (left)
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Quick Wedge Alignment |
Here is the method I use to quickly align the N11GPS on
its wedge.
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Installing Bob's Knobs |
| When I received my set of Bob's Knobs (They
replace the philips collimation screws in the secondary), I asked my
friend Robert Berta if he had any tips on installing the knobs. Here
are Bob's instructions (reprinted with his permission):
First... |
Collimating The Nexstar 11 GPS |
| This is the second part of Bob's email. Bob's
excellent description of the collimation process applies equally well
whether you are using a screw driver with the standard screws or Bob's
Knobs:
To do the colimation...aim the scope at a medium to bright star and center
the star in the FOV. Do NOT use the diagonal for this step...it makes it
hard to to since part of the image will be backwards and confusing. In
addition you want to climate for the scope itself and not have that compromised by any inherent error in a diagonal. Instead put the eyepiece
straight through....it helps to aim at a lower star of course to avoid a
awkward position. Now focus the star and than put it a bit out of focus so |
Cleaning The Azimuth Track |
| The N11GPS uses a 'racetrack' arrangement to move
the scope in Azimuth. This consists of three roller bearing moving
around on a metal track. Over a period of time material may accumulate
on the track causing rough tracking. He is another of Bob's great tips
on how to clean the track without unplugging any wires. I follow this
procedure once a year.
....you don't need to unplug anything if you do the following.
Remove the 5 allen screws. Gently lift the round cover up (the orange
ring stays put...pull on the plastic edge above it). Lift at the side
OPPOSITE the side that has all the plugs in it. The few wires are on
the other side so you can tilt it up enough to get to it and clean the
track. Hold the round cover so it doesn't fall off and pull the wires
out. You should be able to raise it 3 - 4 inches. Use a paper towel or small cloth with alcohol on it and after
releasing the RA clutch slowly rotate the fork so you can clean all of
the track. While there also clean the faces of the three roller
bearings. I have cleaned mine once over a year ago and decided to do
it again tonight so I could make sure that what I tell Stephen was
correct. After a lot of use...probably average of 3 nights a
week...all I got was a trace amount of black soot dust...probably some
of the worn off anodizing from the track. Mine was still nice and
smooth although there is a bit of a surface to it..probably to grab
the bearings cleanly. DO NOT grease this track. |
GPS Battery Location |
| The lithium battery used by the GPS receiver in
the N11GPS is located on the back of the small GPS board that is piggeybacked to the compass
board located in the base. To see a picture click here. To get to the
battery you would need to separate the two boards. This is the battery that
saves the memory of the GPS downloaded time/date/satelite DB, etc. While
once it is used it will update very quickly...when you use the scope for the
very first time it takes longer...believe the GPS standard is for a total of
20 minutes to download the complete information it needs. While it may not
seem that long to lock on and work...it is still downloading info in the background on the first use. That is why Celestron says that the
first
time you use it to let it run for an hour or so to ensure it downloaded all
the DB it needed. If you go to a different location it will update the
DB...if a very long way away...say opposite hemisphere...it will take a very
long time to update. Celestron says up to an hour...but it can be cut
shorter if you pull the battery and let it start from scratch. For me..it
seems too much trouble to do that...just let it start running an hour before
you need it ;-) Bob Berta |
Transporting the Nexstar 11 GPS |
| The mirror in the N11GPS is quite heavy. To ensure that the weight of the mirror does no bend the rod it slides on you should always move the mirror to the back of the scope before transportation. This will ensure the mirror is snug. To do this turn the focus knob in a clockwise direction. It takes about forty turns to move the mirror from the front of the scope to the back. |