NexStar Cruiser Beta

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Description

"NexStarCruiser" is software for the Pocket PC which controls a wide range of Celestron NexStar telescopes via a serial port on the Pocket PC. More details further down this page.


NexStarComTester

NEVER POINT YOUR SCOPE DIRECTLY TO THE SUN WITHOUT AN APPROPRIATE SOLAR FILTER SAFELY ATTACHED.

While the telescope is slewing, it is always best to keep an eye on things to insure there are no cable wraps and that the telescope does not make contact with the mount. NexStarComTester
1. Outline
NexStarComTester, hereafter referred to as NSCT, is software for the Pocket PC which allows testing of serial communication between a Nexstar telescope and a Pocket PC running WIN CE3.0, Pocket PC 2002 or Pocket PC 2003 operating systems.

NSCT currently supports the Nexstar GT (hand controls made after Dec 2001), Nexstar 5i/8i, Nexstar GPS, Advanced Series with GoTo and Celestron CGE telescopes. NSCT requires a free RS232C port on the PocketPC most commonly provided by a serial CF card for a wired connection or Bluetooth for wireless control.

NSCT is supplied as-is and free of charge, with no guarantee or liability whatsoever is assumed. Use at your own risk.

The author of this program assumes that you are well familiar with the use of Pocket PCs and general computer control of your Celestron Nexstar telescope. For more information regarding computer control of your telescope, visit Michael Swanson's Nexstar Resource Site.

www.NexStarSite.com/PCControl.htm.

2. Main Control
NSCT basically provides that you know to which COM port the telescopes is linked to. Selecting another port may result in a system hang up, which can only be resolved with a warm boot. You can use the [Search] button to have NSCT find a Nexstar (does not work with wireless serial connections, such as Bluetooth). The iPAQ h2210 and hx4700 allocate the serial Bluetooth to COM8.

Select a COM port from the combo box. If connection can be established successfully, the Scope Response text box will show the scope's version data and operating status. For Nexstar GT models, you must enter 'RS-232C' mode from the hand control menu before the scope will accept commands. Note that NSCT does not disable scope tracking of GT mounts while tracking of 5i/8i scopes is disabled.

As you select a command from the combo box at the bottom, its code will be displayed in the command text box and executed as you tap on the [Send] button. The response from the scope is decoded in clear text, while "Get" commands add the scope's raw HEX code to the response.

To clear a text box double-tap on it.

You may as well wish to enter a scope command manually in the Command text box. NSCT checks the command syntax, but please make sure to use Nexstar commands only. False commands will basically be ignored by the scope, however, the author does not exclude the possibility of damage should false commands be sent. Make sure to refer to your Nexstar manual for details about available commands and be aware that commands can be case sensitive.

Some responses to manually entered commands using the SIP will not be presented in clear text. They are shown as raw data as received from the scope and are garbled in case returned data is binary. A soon as the SIP is opened NSCT switches to manual. As you select a preset command from the combo box responses will be decoded to clear text.

The [Abort] button is provided for safety, should you need to stop scope slewing.

Tap on the [Poll] button to force data from the serial port manually or to clear the receive buffer.

[Left], [Up], [STOP], [Down], [Right] slew the scope at 3 deg/sec to the respective direction. Tap and hold to slew, release to stop. The direction buttons are disabled if the connected scope is a GT which does not support slew commands. The [STOP] button is provided for safety should the scope not respond when a direction button is released.

Troubleshooting

The author of this program assumes that you are well familiar with the use of Pocket PCs and general computer control of your Celestron Nexstar telescope. Before experimenting, please get help from a friend or an online user group.

Contents
1. Compatibility
2. Telescope
3. Pocket PC
4. Software
5. Connectivity

1. Compatibility
NSCT works with all current (as of July 2004) Nexstar telescopes, the GPS series, "i" series and the GT series as well as CGE and AS-GT (Advanced Series with GoTo) telescopes. Nexstar 60/76/80/102/114/4/130 telescopes with the new handset introduced in December 2001 use a command set identical to that used by the Nexstar GPS telescopes and are therefore compatible. Older 60/80/114 telescopes supplied until December 2001 are not supported.

NSCT was succesfully tested on a HP iPAQ h2210 device with XScale processor running Pocket PC 2003 (Japanese Version) and a serial CF card (Rex CF60) interface to a New GT and 5i Nexstar telescope. Operation on other devices, hardware and setups cannot be tested by the author.

2. Telescope
The telescope must be aligned before it will accept commands. To test indoors, simply perform a Quick Align or an Auto Align, accepting the locations pointed out for the two stars.

For some models of Nexstar (N5/8 and the current version of the N60/80/114/4/130), you must enter 'RS-232' mode from the hand control menu before the scope will accept commands.

NSCT and almost all other astronomy programs can only communicate with the telescope via the port on the bottom of the hand control - not the ports on the base of the mount.

3. Pocket PC
Your Pocket PC must be running Windows CE 3.0, Pocket PC 2002 or Pocket PC 2003 on ARM/XScale processors. NSCT is not designed for WinCE Handhelds, Palm, Clie or other PDAs.


4. NCST Software
Be sure there are no other programs using the serial port. On a Pocket PC, be sure to disable ActiveSync.

Upon erroneous selection of a scope COM port, such as one allocated by system default (IrDA, Bluetooth, etc), the Pocket PC may not react on further port selections. To remedy, warm boot the Pocket PC and do all over again.

The Scan function can detect wired serial scope connections through externally attached serial ports, such as a serial CF card. Wireless connections which are 100% identical in behaviour can be detected, however, the function is not designed to specifically search for wireless connections. Scan does not check COM ports on the Pocket PC which are by default allocated to built in connectivity, such as IrDA, CIRUart, USB or Bluetooth™.

5. Connectivity
When using a serial port card in the card slot of your Pocket PC, you should use the standard RS-232C control cable widely available at astronomy/telescope dealers. When using the Pocket PCs serial "sync" cable - you must use a special RS-232C control cable to connect to your scope (www.astrogadgets.com).

For wireless connections, please do not use the Scan function; you need to know the COM port number which the Pocket PC's system assigned to the selected wireless connectivity. Example, COM8 on iPAQ h2210 with its built-in Bluetooth driver.

Some combinations of Pocket PCs and Nexstar telescopes are sensitive to the order of events when connecting the two. Try aligning the scope with the Pocket PC disconnected from the hand control. Then connect the Pocket PC and start the control software.

Take a good look at the connector on the bottom of the hand control - insure none of the pins appear bent or misaligned.

A faulty cable might be the problem.

Please close all other applications in order to allocate maximum possible main memory to PNSC. Tap on a headline bar on each screen to access the relevant Help chapter.

NEVER POINT YOUR SCOPE DIRECTLY TO THE SUN WITHOUT AN APPROPRIATE SOLAR FILTER SAFELY ATTACHED.

While a GoTo slew is in progress, it is always best to keep an eye on things to insure there are no cable wraps and that the telescope does not make contact with the mount. Pocket NexStarCruiser
1. Outline
PocketNexStarCruiser, hereafter referred to as PNSC, is software for the Pocket PC which drives a telescope to objects in its database. PNSC currently supports the NexStar GT (hand controls made after Dec 2001), NexStar 5i/8i, NexStar GPS, Advanced Series with GoTo and Celestron CGE telescopes. PNSC will slew to a selected object without the added complications of a laptop computer. This function requires a free RS232C port on the PocketPC most commonly provided by a serial CF card. PNSC does not currently support telescopes other than those listed.

PNSC is supplied as-is and free of charge however with no guarantee or liability whatsoever is assumed. Use at your own risk.

The author of this program assumes that you are well familiar with the use of Pocket PCs and general computer control of your Celestron NexStar telescope. For more information regarding computer control of your telescope, visit Michael Swanson's NexStar Resource Site.

www.NexStarSite.com/PCControl.htm.

2. Setup
Prior to using PNSC you must configure the program via the Setup screen. The first time you run the program you will automatically be presented with Setup.

Tap on the PocketNSC icon to start the program. When the Setup screen appears you are required to enter your local information, such as geographical coordinates and time zone. Check DST if Daylight Saving Time is currently being observed in your location. Please make sure to have a serial port correctly installed and connect the PocketPC to your telescope. Tap on the Scope icon to open a guide for two-star alignment.

PNSC allows you to enter up to 20 observation sites. Select a New Site and enter a name for it. Then enter the site data or use the GPS function. A site is saved as you tap on the [OK] button.

Perform an alignment on your scope and if you have a NexStar GT, activate RS-232 mode via the Menu. Tap on Scan to find the COM port to which your NexStar telescope is connected. You may as well choose "No scope", if you wish to explore the functions in simulation mode.

The Scan function only works with external wired serial port adapters. If you use a built-in port of the Pocket PC, such as Bluetooth, you need to know the correct COM port number and select it from the SCOPE PORT combo box.

If the hand control version is 4.10 or later, you can read the current HC coordinates and time tapping on the [?] button next to the [> Scope] button. Tap on [> Scope] to write the coordinates from the setup screen plus the current time to the HC. This function is not available for GT mounts and HC's earlier than version 4.10.

Make sure to set your slew limits and check 'Use altitude control' if you wish PNSC to prompt in case an object lies beyond the limits as set in the Max and Min combo boxes.

The Telescope icon changes to the Two-Star Alignment Assistant.

The Clock and Battery icons take you to the system settings in which you can adjust the clock and power management. Before using PNSC with a telescope, make sure that the PocketPC will not enter its auto-power-off mode. These buttons may not work with all PocketPCs, in which case please go to System/Settings.

3. Main Control
The Main Control screen provides the equatorial and horizontal coordinates at which the scope is currently pointing. Tap on Get to refresh or check Auto to have PNSC update the coordinates in intervals of 2 seconds.

The Log button opens a screen which displays the most recently sent commands and scope responses.

Tap on the Sun icon to view now-data of the Sun, tap on the Moon icon to view now-data of the Moon. The Moon icon shows the current approximate Moon phase.

The URDL buttons allow manual slewing of the scope (not supported for GT mounts). Tap and hold on a direction button and release the stylus when a target position is assumed. Alternatively, you can use the four hot keys of the device, from left to right: L, D, U and R. Press and hold a key down to slew, release to abort.Tap on the icon in the center of the direction buttons to abort slewing. Make sure to hold the direction buttons or hot keys firmly down. Just a brief touch may render slewing out of control. In such a case, tap on the icon in the center of the direction buttons or on the little joystick button on the Pocket PC to abort slewing.

The three combo boxes at the right allow selection of slew rates for manual slewing, changing tracking modes and selecting high (24-bit) or low (16-bit) accuracy for GoTo and Get equatorial and horizontal coordinates. The combo boxes are not provided for the GT mount since the GT does not support manual slewing, track mode setting and accuracy setting via its HC port. The GT mount supports low (16-bit) data accuracy only. To slew the GT manually, please refer to Scope Navigation.

The checkbox at the right of the Slew rate selection is provided to synchronize left/right slewing speed with up/down slewing speed. The NexStar scope slews slower as its pointing declination increases towards +90 deg or decreases towards -90 deg. The slewing speeds are equal in both directions at 0 deg declination. By default the NexStar mode is selected. Check the box to synchronize slew speed. This function is not available for NexStar GT mounts.

At the buttom of the screen are seven icons that will take you to other information and setting screens. They can as well be selected from the pull-up menu.

4. Object List
This is a database of celestial objects to GoTo.

At the top of the screen are two combo boxes, the upper selecting a category, the lower an object listed therein.

Upon selection of a category and an object positional data of that object is displayed.

Tap on GoTo to slew to the object, tap on ABORT to stop.

If a Goto object is not in the field of view, the [Spiral] button can be used to let the scope spiral out of its current position hopefully towards the target object. Five option buttons are provided to select the speed at which the scope spirals, slowest with the left option button. Typically, use slow speeds for narrow fields of view, such as CCD cameras mounted on scopes, medium speed for eyepiece observation and faster speed for wide fields, such as provided by short focal length optical systems. This function is not supported by GT mounts.

The [Sync] button is enabled as star objects are selected. A Sync improves pointing accuracy around the area of a selected star (the sync'd star), however, the initial alignment accuracy will deteriorate. A Sync is recommended if you wish to explore objects in a given constellation at high pointing and tracking accuracy.

5. Scope Navigation
This screen is primarily provided for GT mounts which do not support manual slewing under serial control. Scope Navigation allows slewing the scope to a designated horizontal position at 1 deg accuray.

Tap on the left image to select an azimuth angle, and tap on the right image to select an altitude. Moving the stylus on the images will change positions as well. Selected positions are displayed underneath the images. Scope coordinates are horizontal coordinates in HEX notation for the telescope and are provided for reference only.

For a rough selection of horizontal coordinates you may wish to use the North, East, South and West buttons for the azimuth, and the 0 to 90 buttons for altitude.

Tap on SLEW to move the scope to a so selected position, tap on ABORT to stop slewing. Tap on GET to retrieve the current horizontal scope position.

6. Select Scope
This function is not related to navigation tasks, but will be used by simulations to obtain field-of-view data, such as in Binary Stars.

Select the Celestron telescope in use from the upper combo box and an eyepiece thereunder. Tap on the eyepiece icon to switch to a CCD camera selection. Select a barlow or reducer from the bottom combo box, if so equipped.

Tap on the eyepiece icon to change to a selection of CCD (web) cameras. Tap again on that icon to return to the eyepiece selection.

After specifiying a scope and eyepiece or CCD camera tap on the icon at the top right to verify the field of view on a 3 deg square image of the Plejades.

Tap on the Data button to view the theoretical performance data of the selected telescope. Please note that this data is based on perfect optics and ideal viewing conditions. You get closest if you operate your Nexstar outside Earth's atmosphere. Tap on the text to toggle metric and inch conversions.

7. Alignment Assistant
Provided to assist you in the selection of a suitable pair for 2-star-alignment.

Besides confirming the system clock, please make sure that your correct local geographical coordinates and time zone are entered.

Shown first is a list of presently available stars for alignment. Z-xx means zenith distance. Checkmark "GT" if your are using a GT mount which stores only the first 21 of other NexStar mounts.

Tap on the constellation icon to calculate the most suitable pairs with their angular separation. At the bottom of the screen are two combo boxes which allow you to widen the default range of altitude and angular separation of potential alignment stars. Please select pairs within 15 to 70 degrees altitude and make sure not to use Polaris in EQ N/S tracking mode because the north point is the polar alignment reference point.

Tap on the chart icon to view all visible alignment stars on a zenith projection. Tap an hold on a star to confirm its current azimuth and altitude.

Tap on the scope icon to update the list of available alignment stars.

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Pocket NexStarCruiser
8. Star Compass
This is a very rough compass which uses the NexStar alignment stars to find directions. Make sure that the current set location and date/time are correct. Tap on Update Stars to refresh the time and then select a star which you can clear identify in the sky.

To align the compass turn the Pocket PC so as the 'needle' points at the current position of the selected star. When a star is below the horizon or when extremely cloudy this compass is obviously useless. However, if updated, the list of stars will always contain those above horizon.

Please DO NOT use this compass, if you need precise direction angles, not even for north pointing your scope.

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9. Dew Point Estimation
Calculates the dew point temperature based on ambient temperature and relative humidity. When the difference between ambient and dew point temperatures is small, dew is likely to form on the lens, mirror or corrector plate.

Scroll the bars to set to current ambient humidty and temperature conditions.

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10. Binary Stars
Actually a part of the Object List, this screen allows to pick a pair from a list of binaries (WDS catalog) which are presently no closer then 0.5 arc seconds.

Tap on GoTo to slew to a selected binary pair, tap on ABORT to stop slewing. Tap on DATA to find out more about the selected binary star, such as its ephemerides and positional data.

This data provides that a telescope is specified under Select Scope.

Data, such as minimum power and minimum aperture are based on ideal conditions and optics. The same applies to the judgement whether or not a selected scope is capable of resolving the pair.

Notes:

1. The binary pair is shown as viewed through a NexStar SCT with star diagonal and eyepiece.

2. PA = Position angle (0 to 360 degrees) counter clockwise from North thru East and South.

3. SEP = Separation in seconds of arc.

4. FOV = Field of View, the diameter of the outermost circle in seconds of arc.

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11. Jovian Moons
This screen allows you to confirm the current position of the Jovian Moons and further lets you simulate the motion of these four largest moons of Jupiter in selectable intervals.

To simulate select an interval in hours and tap on [>] to simulate forward in time or on [<] for backwards. To pause tap on [||]. To reset tap on NOW.

Toggle the Edge/Orbit button to change orbit viewing angles. The edge view accounts for Jupiter's current tilt of rotation axis and parallactic (diurnal) angle.

Telescope view reflects a NexStar SCT equipped with star diagonal and eyepiece.

The text box at the bottom show the XY coordinates of the moons plus the distance measured in Jupiter radii. X is positive for West, Y is positive for North as seen in an upright image, such as observed with binoculars.

Tap on GoTo to slew to the now-position of Jupiter, tap again on GoTo to abort if need be.

Tap on the picture box and use the hardware cursor keys to shift the center position of the Jovian system if need be. Double-tap to return it to the center.

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12. Planet Transit
Calculates the estimated times of central transit of the planets listed in the combo box.

Dates and times in heliocentric UT and Geocentric UT are given for the central transit.

Tap on Last, Coming or Next to confirm three event arount current date.

Tap on Chart to view a 40 x 40 arc minutes field around the star. The small images are approximately 20 arc minutes wide.

Tap on System Data to view data of the exoplanet and its mother star, tap on the top image to change the views.

Tap on GoTo to slew to the now-position of a selected exoplanet star, tap again on GoTo to abort if need be.

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13. Earth Moon
An orientation map for the moon. Tap on Labels to toggle major labels on and off.

Tap on the Moon to draw a rectangle. Place the rectangle to a desired location by tapping on that location on the map. To magnify the area covered by the rectangle tap on [Magnify]. The magnified excerpt is 5 times larger.

Tap on Features to overlay a combo box from which you can select a feature, such as a Mare or Crater. Upon selection, positional data of that feature will be displayed. Tap on OK to mark the selected feature on the Moon map. Then you may use either mode for viewing the area around the feature enlarged.

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14. Digitized Sky Survey
Allows you to retrieve an image from the Digitized Sky Survey centered around the current equatorial position of the telescope which appear by default in the relevant text boxes. These values can be edited in the same notation to other center coordinates.

Right ascension in [xxhxxmxxs]
Declination in [xxdxx'xx"]

You may as well use spaces instead of h,m,s and d,',"
For epoch, enter a year with decimals between 1950 and 2500, typically the epoch of the equatorial coordinates. Tap on Now to insert now-time in this year with decimals.

Width and height are numericals in arc minutes determining the rectangular (or square) excerpt of the sky image to be downloaded. The maximum value is 60 x 60'. By default the field of view as calculated in Select Scope will be selected.

The combo box under "Survey to retrieve from" allows selection from various DSS surveys.

Learn more about the surveys visiting the The STScI Digitized Sky Survey's web site. The data retrieval entry form is at http://stdatu.stsci.edu/cgi-bin/dss_form

The STScI Digitized Sky Survey
(c)1994 Association of Universities
for Research in Astronomy Inc.
http://stdatu.stsci.edu/dss/index.html

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15. SLOAN Digital Sky Survey
This tool accesses the SLOAN Digital Sky Survey and retrieves JPEG images centered around the input Right Ascension and Declination in regions of the sky covered by the Sloan Digital Sky Survey. Since to date the survey has not yet covered the entire sky, requests may end up into a corresponding message: "Requested (ra/dec) is outside the SDSS footprint".

Enter Right Ascension and Declination (epoch 2000) in degrees with decimals, specify the image dimension in pixels (from 16 to 1000 for each width and height) and the resolution of the desired image in arc seconds per pixel (from 0.015"/pixel to 50"/pixel).

Tap on "Field of view?" to calculated the field of view of the expected image in width, length and across.

Further, three checkboxes are provided
1. NSEW Grid: check to add a North, South, East, West grid.
2. Labels: check to add Right Ascension, Declination and resolution data.
3. Invert: check to invert the expected image.

Tap on download to retrieve the image with Internet browser.

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16. Measuring Apparent FOV
Measurement of the approximate apparent field of view of an eyepiece can be accomplished by counting the time a star moves from one edge of the field in the eyepiece to the opposite. Alternatively, the GoTo scope can be employed for this purpose.

1. Transit Method
Slew to a bright star nearest declination 0 deg and align it to one edge of the field. As done tap on Measure Now. PNSC will get the declination from the scope. The declination is required to compensate for the distance to 0 deg declination, however, the closer the better. Tap on STOP as the star reached the other end of the field and read the values measured.

2. Use Scope Coordinates
Slew to a bright star and align it to one edge of the field. Tap on 1st Position and PNSC will get the coordinates. Move the scope at a slow rate so as the star is positioned opposite of its previous position and tap on 2nd Position. PNSC will get the coordinates of this second position and calculate the angular distance, thus the true field of view and the apparent field of view at given magnification as set in Select Scope.

It is important for both methods that the two positions of a star span over the entire diameter of the field of view.

Note that tracking will be set to OFF as you open this screen. Reset tracking to its previous mode after returning to the Main Control screen. If a GT mount is connected, set tracking to OFF on the hand control and return to the previous tracking mode again on the hand control. The GT mount does not support tracking commands via serial control.

If you select a CCD camera in place of an eyepiece this screen will not open.

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17. Image Orientation
In space there is no such thing as "up or down", however for software processing knowledge of the orientation of an image makes it easier to flip and turn it to its terrestrial orientation. Being aware of the orientation in the eyepiece is also helpful when checking against a star chart. Orientation is other than terrestrial when the image in the eyepiece goes in a different direction than expected.

Select a diagonal, star diagonal (90°), erecting prism (45°) or no diagonal (none). Select eyepiece or a CCD, or a CCD over an eyepiece (afocal imaging). Upon any selection, the terrestrial landscape image with a superimposed alphabet "R" will show the orientation as observed in Schmidt-Cassegrain and Maktsutov telecopes. The display of image orientation with CCDs provides no rotation of the camera.

Tap on the landscape image to view the optical path of a Cassegrain telescope for reference. Tap again to return.

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18. Mars View
Computes the current central meridian of Mars, i.e., the planet's longitude facing Earth. The surface map is centered on the central meridian with North up and updated every 10 seconds.

To slew the scope to Mars tap on GoTo. Tap on Abort to abort slewing or press the small joystick button on the Pocket PC.

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19. Jupiter View
Computes the current central meridian of Jupiter, i.e., the planet's longitude facing Earth. The surface map is centered on the central meridian with North up and updated every 10 seconds.

The GRS is a huge storm in Jupiter's atmosphere which shifts its position over time. As of March 28, 2006 the position of the GRS is on 109° longitude in system II. Jupiter's observable 'surface' has two general systems of rotation that differ by approximately 5 minutes: System I (9 hours 50.5 minutes) and System II (9 hours 55.7 minutes). Most of the planet falls under the System II rotation rate, while System I rotation applies to the Equatorial Zone. If the GRS has moved elsewhere, it will transit 1 2/3 minutes late for every 1° of longitude greater than 109° or 1 2/3 minutes early for every 1° less than 109°.

Jupiter View computes the approximate time until a next transit of the GRS.

To slew the scope to Jupiter tap on GoTo. Tap on Abort to abort slewing or press the small joystick button on the Pocket PC.

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20. GPS Function
The use of GPS requires a GPS module attached to a free serial port of the Pocket PC. GPS modules are typically provided in the form of a CF type card. This function will read the GGA packet of NMEA-0813 data at 4800 Baud. It is not possible to send and store the GPS data to the NexStar telescope's hand control.

As you tap on Search GPS, PNSC will search the Pocket PC for a serial port with a GPS module. If not found an error message will prompt so. If found, GPS data will be retrieved in 1 second intervals and be displayed in raw format on the world map for reference only.

When the system obtains data from at least three satellites, geographical coordinates, etc. will be displayed in the text boxes. Then you may wish to set the internal clock of the Pocket PC and/or take the GPS coordinates over to PNSC's Setup Screen. If GPS data is not obtained from at least 3 satellites, it won't be made available for further use.

If the Search function cannot detect a GPS device, then please use the Select combo box to set the port manually, provided you know to which COM port the GPS device is allocated. A wrong choice may cause a system error which can only be recovered with a warm boot.

Make sure to use GPS under unobstructed skies. It will hardly work indoors and often not under a large tree.

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21. Backslash and Autoguide
This function is not supported by GT mounts.

Here you can set the backslash compensation values for all four directions. Tap on a checkbox between the scrollbars to synchronize the positive and negative values each for azimuth and altitude. Uncheck to set them individually. Please refer to your Celestron telescope manual for details about backslash and make sure to visit
http://www.nexstarsite.com/
to refer to the best source of such information. If in doubt, set all backslash values to 0.

The speed for the autoguide port can be set for azimuth and altitude directions individually in units of Sidereal movement from 0.01x to 1x. Tap on the checkbox between the scrollbars to synchronize azimuth and altitude. PNSC first reads the current values from the scope to set the scrollbars when opening this screen for the first time after starting PNSC. This process may take 2 or 3 seconds.

Tap on the checkbox in the PEC frame to engage Periodic Error Control, if this function is available on your Celestron scope model. Uncheck to disengage. Please check on your hand control whether this function is available to you. There will be no error message if your scope does not support PEC.

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22. Home Position
This menu item is provided to slew the scope to 0 degree azimuth and altitude, which is basically North and Index Mark for alignment in Alt/Az tracking mode. This will shorten your next alignment session.

When slewing to home position the altitude limit control, if enabled, is overridden for this purpose only. Slewing can be aborted by tapping on the STOP button or pressing the center knob or pad on the PocketPC.

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Troubleshooting

The author of this program assumes that you are well familiar with the use of Pocket PCs and general computer control of your Celestron NexStar telescope. Before experimenting, please get help from a friend or an online user group.

Contents
1. Compatibility
2. Telescope
3. Pocket PC
4. Software
5. Connectivity
6. GPS Module

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Pocket NexStarCruiser Troubleshooting
1. Compatibility
PNSC works with all current (as of July 2004) NexStar telescopes, the GPS series, "i" series and the GT series as well as CGE and AS-GT (Advanced Series with GoTo) telescopes. NexStar 60/76/80/102/114/4/130 telescopes with the new handset introduced in December 2001 use a command set identical to that used by the NexStar GPS telescopes and are therefore compatible. Older 60/80/114 telescopes supplied until December 2001 are not (yet?) supported.

PNSC was succesfully tested on a HP iPAQ h2210 device with XScale processor running Pocket PC 2003 (Japanese Version) and a serial CF card (Rex CF60) interface to a New GT and 5i NexStar telescope. Operation on other devices, hardware and setups cannot be tested by the author.

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Troubleshooting
2. Telescope
The telescope must be aligned before it will accept commands. To test indoors, simply perform a Quick Align or an Auto Align, accepting the locations pointed out for the two stars.

For some models of NexStar (N5/8 and the current version of the N60/80/114/4/130), you must enter 'RS-232' mode from the hand control menu before the scope will accept commands.

Please bear in mind that it takes a GT mount longer to perform a Goto slew. For this reason, PNSC will prompt that the scope is still slewing if another Goto slew is initiated too early. If the mount is still slewing although it appears to have resumed tracking, please check the display of the hand control to confirm. As long as the slash in the upper right corner rotates, the mount is slewing.

PNSC and almost all other astronomy programs can only communicate with the telescope via the port on the bottom of the hand control - not the ports on the base of the mount.

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Troubleshooting
3. Pocket PC
Your Pocket PC must be running Windows CE 3.0, Pocket PC 2002 or Pocket PC 2003 on an ARM/XScale processor. Maximum compatibility and speed are achieved with current XScale processor based devices. PNSC is not designed for WinCE Handhelds, Palm, Clie or other PDAs.

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Pocket NexStarCruiser Troubleshooting
4. PNSC Software
Insure correct registration of geographical coordinates and time zone of the observation site.

Be sure there are no other programs using the serial port. On a Pocket PC, be sure to disable ActiveSync.

Upon erroneous selection of a scope COM port, such as one allocated by system default (IrDA, Bluetooth, etc), the Pocket PC may not react on further port selections. To remedy, warm boot the Pocket PC and do all over again.

The Scan function can detect wired serial scope connections through externally attached serial ports, such as a serial CF card. Wireless connections which are 100% identical in behaviour can be detected, however, the function is not designed to specifically search for wireless connections. Scan does not check COM ports on the Pocket PC which are by default allocated to built in connectivity, such as IrDA, CIRUart, USB or Bluetooth™.

If you believe that scope setup and interface hardware is correctly set up, increase CMD DELAY and try again.

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Pocket NexStarCruiser
Troubleshooting
5. Connectivity
When using a serial port card in the card slot of your Pocket PC, you should use the standard RS-232C control cable widely available at astronomy/telescope dealers. When using the Pocket PCs serial "sync" cable - you must use a special RS-232C control cable to connect to your scope (www.astrogadgets.com).

For wireless connections, please do not use the Scan function; you need to know the COM port number which the Pocket PC's system assigned to the selected wireless connectivity. Example, COM8 on iPAQ h2210 with its built-in Bluetooth driver.

Some combinations of Pocket PCs and NexStar telescopes are sensitive to the order of events when connecting the two. Try aligning the scope with the Pocket PC disconnected from the hand control. Then connect the Pocket PC and start the control software.

Take a good look at the connector on the bottom of the hand control - insure none of the pins appear bent or misaligned.

A faulty cable might be the problem.

6. GPS Module
The GPS function of PNSC was tested with a "CFGPS2" card from I-O Data with a 4800 Baud serial interface; other GPS receivers are not tested.

Basically supported are GPS modules conforming to NMEA-0183 standard, presenting the GGA data packet first.

Make sure that the GPS module is hardware-compatible with the Pocket PC and that it is connected to a serial port, most commonly provided by a Compact Flash type GPS card module.

When searching for a GPS module, PNSC scans all registry entries for serial ports looking for an instring "gps" (not case sensitive) in the PnPID section. If the product ID of the vendor of your GPS card does not contain that instring, then it will not be detected. In that case please contact the author with the data in the PnPID section. Open HKEY_LOCAL_MACHINE\Drivers\Active\00~99 and look for the COM port while the GPS card is inserted. In most cases, it is the last or second last folder underneath \Active\.

Make sure to use GPS in an unobstructed area. An external antenna will make big difference for insensitive receivers. GPS will not work indoors or in obstructed areas.

GPS data can only be provided to PNSC's Setup Screen. It can not be sent to the NexStar telescope.

Installation Instructions

Notes The Beta version is documented by a help file, but Please use at your OWN RISK. The author assumes that the user is well familiar with the use of PocketPCs and general computer control of her/his Celestron NexStar telescope.
Requirements free serial RS2332C port or
or a serial Bluetooth connection for wireless scope control. Optionally a GPS module, such as a CF GPS card.
Tested with: hx4700, iPAQ h2210 (O/S-JPN), Rex CF60 serial CF card, Free2Move Serial Bluetooth module, NexStar GT80, NexStar 5i telescopes.

Requires VBCE2.0 Visual Basic runtime

Tags

Visual BasicUtilityastronomyVBVBCE 2.0

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