iOptron® GEM28 German Equatorial Mount Instruction Manual Product GEM28 and GEM28EC
Read the included Quick Setup Guide (QSG) BEFORE taking the mount out of the case! This product is a precision instrument and uses a magnetic gear meshing mechanism. Please read the included QSG before assembling the mount. Please read the entire Instruction Manual before operating the mount. You must hold the mount firmly when disengaging or adjusting the gear switches. Otherwise personal injury and/or equipment damage may occur.
Table of Content Table of Content ................................................................................................................................................. 3 1. GEM28 Overview .......................................................................................................................................... 5 2. GEM28 Terms ................................................................................................................................................ 6 2.1.
5.4.5. Set Guiding Rate............................................................................................................................. 27 5.4.6. Set Parking Position ....................................................................................................................... 28 5.4.7. Set Tracking Rate ........................................................................................................................... 28 5.4.8. Meridian Treatment ...............................
1. GEM28 Overview The iOptron® GEM28 and GEM28EC mount is the next-generation compact German equatorial mounts. Like their predecessors the GEM28 is designed with portability in mind, weighing in at only 10 lbs it can support up to a 28lb payload an incredible 2.8 mount weight to payload ratio. We achieved this using design methods developed to reduce mount mass in our CEM family of mounts.
2. GEM28 Terms 2.1. Parts List1 SHIPPING CONTENTS Your new GEM28 mount comes in two shipping boxes. One box contains a GEM28/GEM28EC mount, hand controller, one 10.4 lbs (4.7kg) counterweight, counterweight shaft, tripod spreader and accessories. The other box contains a tripod.
2.2. Identification of Parts Dovetail saddle DEC gear switch DEC Unit Polar axis cover RA Unit Polar scope Alt. adj. knob Azi. locking screw Counterweight Az. adj. knob CW bar CW safety screw Tripod Alignment Peg Center Rod Knob Accessory Tray Tray Locking Knob Tripod Leg Lock Figure 1.
2.3. GEM28 Port RA Unit RA Unit (Top) DEC Unit Figure 2. Ports on a GEM28 mount On RA Unit: I/O Switch: Power switch LED: Power indicator DC 12V IN: DC power socket to power the mount (2.1mmX5.5mm, center positive) HBX (Hand Box): For connecting to an 8409 Hand Controller GUIDE: ST-4 compatible autoguiding port. The wiring is shown in Figure 3 Figure 3.
RA+ DEC+ RADEC- HBX Port USB Port Figure 4. Go2Nova® 8409 hand controller 2.4.1. Key Description MENU Key: Press “MENU” to enter the Main Menu. BACK Key: Move back to the previous screen, or end/cancel current operation, such as slewing. ENTER Key: Confirm an input, go to the next menu, select a choice, or slew the telescope to a selected object. Arrow (▲▼◄►) Keys: The arrow keys are used to control the movement of DEC and R.A. axes.
The LCD screen will switch to the information screen, as indicated in Figure 6, with pressing any button. Magnitude Declination Altitude N/S Hemisphere Target Name Right Ascension Azimuth Mount Status Slew Speed Current Time Figure 6. 8409 HC LCD Information Screen 1. Target Name/Mount Position: displays the name of the target that telescope is currently pointed to or the current mount position.
3. GEM28 Mount Assembly 3.1. GEM28 Mount Assembly NOTE: The GEM28 mount is a precision astronomical instrument. It is highly recommended that you read the entire manual and become familiar with the nomenclature and function of all components before starting the assembly. WARNING: DO NOT rock the counterweight shaft rigorously. This may damage the worm/drive gear system and such damage will not be covered by warranty. Step 1.
Step 3. Attach mount head Retract the 2x Azimuth (Azi) Adjustment Screws from both sides to leave ample space for the alignment peg to be fitted in between the 2x Azi Adjustment Screws. Remove the 2x Azi Locking Screws from the mount base and insert them into the opening next. Secure the mount head by tightening the Azi Locking Screws into the M6 holes on the tripod. Azi. Adj. Screw Azi. Locking Screw Figure 9. Attach the mount Level the mount by adjusting the tripod legs.
Push Button Wrench Lat. Adj. Knob Latitude Scale Latitude Locking Lever Figure 11. Adjust latitude You may lift the Latitude Locking Lever handle by push the Push Button on this ratchet lever to disengage gear teeth and rotate freely for quick adjustment. There are four RA axle locking positions for the GEM28 mount: Zero Position, East and West position, and storage position. Figure 12.
Step 6. Install counterweight Before putting on CW, make sure the mount is at its zero position, i.e., CW shaft points to the ground. Insert Allen wrench to lock the RA axle and disengage the R.A. Gear Switch to set the R.A. axis free before loading the CW. Remove the CW Safety Cap at the end of CW Shaft. Glide the CW over the shaft with the larger opening facing down. Tighten the CW Locking Screw to hold the CW in place. Place the Safety Cap back onto the shaft.
Center Adjusting Block Saddle Locking Knob Figure 15. GEM28 Vixen dovetail saddle with Center Adjusting Block To mount a telescope on to the mount, release the dovetail Saddle Locking Knob and slide the telescope dovetail plate into the saddle. Tighten the Saddle Locking Knob. There are two threaded holes on the side of the dovetail saddle for mounting an iOptron mini autoguiding system, iGuider. Figure 16. iGuider mini-autoguiding system Step 8.
Figure 17. Balance a telescope CAUTION: The balancing process MUST be done with Gear Switch at the total disengaged position! Otherwise it might damage the worm system. Return the mount to Zero Position after balancing and engage gear switches. Step 9. Connect cables Use the short RJ11 cable to connect the DEC control unit to the DEC port of the RA control unit. Figure 18. Connect DEC cable Connect the Go2Nova® 8409 Hand Controller to the HBX port on the RA unit.
Plug optional GPS module into the iPORT with a coiled cable. When powering on, GPS ON sign should be displayed at the upper right corner of the hand controller. You may disconnect the GPS module after it picks up satellites signals and displays GPS OK. (It takes a few minutes in normal conditions). STEP 10. Set hand controller If a GEM28 is equipped with a GPS receiver, it will receive the time, longitude and latitude information from satellites after the link is established.
Time Zone Hawaii Hour behind UT Enter UTC Alaska Pacific Mountain Central Eastern -10 -9 -8 -7 -6 -5 -600 -540 -480 -420 -360 -300 To adjust minutes, move the cursor to each digit and use the number keys to input the number directly. Use ▲ or ▼ key to toggle between “+” and “-”. When the time information entered is correct, press ENTER and go back to the previous screen. Note that fractional time zones can be entered.
Connect a mini USB cable between the iPolar and a computer USB port; Figure 20. USB port on an iPolar electronic polar scope Click Connect and start polar alignment by following on screen instructions. Quick Polar Alignment If the mount equipped with an AccuAlignTM optical polar scope, you can use the Quick Polar Alignment procedure to perform the polar alignment.
(5) Use the Hand Controller (MENU => “Alignment” => “Position of Polaris/SigmaOct”) to display the current position of Polaris on the LCD screen, as indicated in the left side of the figure below. For example, June 22, 2014, 20:19:42 in Boston, US (long. W71°08’50” and lat. N42°30’32”, UTC 300 min,) the Polaris Position is 0h45.8m and 40.4m. (a) (b) Figure 23. Polaris position shown on HC (a) and where to put on polar scope reticle (b) (6) Look through the polar scope to find the Polaris.
To set the mount to Zero Position, press MENU=>”Zero Position”=>”Set Zero Position”. Release the Gear Switch to manually return the mount to Zero Position, or use the hand controller to slew the mount to Zero Position. Press ENTER to confirm the zero position. Set the Zero Position or check the Zero Position by using MENU=>”Zero Position”=>”Goto Zero Position” before each session.
4. Getting Started In order to experience the full GOTO capability of GOTONOVA® technology it is very important to set up the mount correctly before observation. 4.1. Setup the Mount and Polar Alignment Assemble your GEM28 mount according to Section 3.1. Mount an OTA and accessories, and carefully balance the mount around the polar axis. Turn the mount power switch on. Check the date and site info. Perform polar alignment. Always check if the mount is at the Zero Position when the mount is powered on, i.e.
4.5. Star Identifying Function The 8409 hand controller has a star identifying function. After Polar Alignment and Set Up Time and Site, slew the telescope to an bright star, manually or using GOTO. Press ? button to identify the star name telescope is pointing to, as well as nearby bright stars if there are any. 4.6. Power-Down Memorization The GEM28 mount can memorize its R.A. and DEC positions if the mount power is lost during operation, even during high speed slewing.
5. Complete Functions of Go2Nova® 8409 Hand Controller 5.1. Slew to an Object Press MENU => “Select and Slew.” Select an object that you would like to observe and press the ENTER key. The Go2Nova® 8409 hand controller for GEM28 mount has a database of over 212,000 objects. Use the ► or ◄ buttons to move the cursor. Use the number buttons to enter the number, or the ▼ or ▲ buttons to change the individual number. Hold on a button to fast scroll through the list.
5.1.8. Enter R.A. DEC Here you can go to a target by entering its R.A. and DEC numbers. 5.2. Sync to Target This operation will match the telescope's current coordinates to Target Right Ascension and Declination. After slewing to an object, press MENU => “Sync to Target” => ENTER. Follow the screen to perform the sync. Using this function will re-calibrate the computer to the selected object. Multiple syncs can be performed if needed.
after the mount slews to it. Press ENTER when finished. The hand controller will prompt you to choose a second star. After centering the second star, the two-star alignment is finished. After the two-star alignment, the altitude and azimuth errors will be displayed. This number can be used to fine tune the Quick Polar Alignment. For example, if the screen shows 7.5" low and 4.3" east, it means that THE MOUNT axis is pointing low and to the east of the Celestial Pole. 5.3.4.
5.4. Settings 5.4.1. Set Time and Site Refer to STEP 10 in Section 3.1. 5.4.2. Set Beep The Hand Controller allows a user to turn off the beep partially, or even go to a silent mode.
5.4.6. Set Parking Position You may park the telescope before powering off the mount. This is very useful if the mount is on a permanent pier or the mount will not be moved in between observation sessions. The mount will keep all the alignment info and reference points. There are five parking positions. Two positions that park the scope horizontally (Horizon Position). Two positions that park the scope vertically (Zenith Position). “Current Position” will park the scope at its current position.
5.4.12. Language Select one of supported menu languages. Currently it has English and Chinese. 5.4.13. Set RA Guiding (GEM28EC Only) You can turn off R.A. guiding by selecting “Filter R.A. Guiding” to allow the high precision encoder to correct the tracking error, or turn the R.A. guiding on by selecting “Allow RA Guiding” to allow the mount to receive guiding corrections from the autoguiding software. 5.5. Electric Focuser This function controls an iOptron electric focuser. 5.6.
5.6.3. PEC Data Integrity This function will check the recorded PEC data integrity. 5.7. Edit User Objects Besides various star lists available in the hand controller, you can add, edit or delete your own userdefined objects. This is especially useful for newly found comets. You can also add your favorite observation object into the user object list for easy sky surfing. Up to 60 comets and other user objects can be stored. 5.7.1. Enter a New Comet Press MENU => “Edit User Objects” to set user objects.
Add a New Object Browse Objects Delete an Object Clear All Objects Select “Add a New Object”. A screen will be displayed asking you to Enter R.A. and DEC coordinates: Enter R.A. and DEC R.A.: 00h00m00s DEC: +00d00m00s You may enter the R.A. and DEC coordinates of the object you want to store, and press ENTER to confirm. A more useful application of this function is to store your favorite viewing objects before heading to the field. When the “Enter R.A. and DEC” screen appears, press the MENU button.
6. Maintenance and Servicing 6.1. Maintenance Do not overload the mount. Do not drop the mount as this will damage the mount and / or permanently degrade GoTo performance and tracking accuracy. Use a wet cloth to clean the mount and hand controller. Do not use solvent. The mount worm/gear meshing can be adjusted to accommodate payload or temperature changed. Please refer to the instruction in Appendix.
Appendix A.
Appendix B. Go2Nova® 8409 HC MENU STRUCTURE MENU Select and Slew Solar System Mercury Venus Mars Jupiter Saturn Uranus Neptune Sun Moon Deep Sky Objects Named Object Messier Catalog NGC IC PGC Caldwell Catalog Abell Catalog Herschel Catalog Stars Named Stars Double/Multi Stars Hipparcors Catalog Comets Asteroids Constellations Custom Objects User Defined Comets Other Objects Custom R.A. and DEC Sync.
Alignment Position of Pole Star One Star Alignment Two Star Alignment Three Star Alignment Solar System Align Polar Interate Align View Model Error Clear Alignment Data Settings Set Time and Site Set Beep Set Display Set Maximum Slew Rate Set Guiding Rate Set Parking Position Horizon Position 1 Zenith Position 1 Horizon Position 2 Zenith Position 2 Current Position Set Tracking Rate Sidereal Rate Lunar Rate SolarRate King Rate Custom Rate Meridian Treatment Set Position Limit Set Behavior Set Alti
Electric Focuser PEC Options PEC Playback Record PEC PEC Data Integrity Park Telescope Edit User Objects User Defined Comet Add a New Comet Browse Comets Delete a Comet Clear All Comets Other Objects Add a New Object Browse Objects Delete an Object Clear All Objects Firmware Information Zero Position Goto Zero Position Set Zero Position Some functions are mount dependent.
Appendix C. Gear Meshing Adjustment CEM26/GEM28 gear is designed adjustable by customer although in most cases not necessary. If you experienced DEC/RA motor stall occasionally, or there is free play between the worm and gear, follow this instruction to adjust the gear meshing. Tool needed: 2mm and 3mm hex keys. To Adjust DEC Gear: Disengage DEC gear switch. Rotate DEC saddle to exposure the small hole (3mm in diameter) that is blocked by the dovetail saddle.
If the motor stalls or the mount does not tracking smoothly, most likely the meshing is too tight. You may loosen it by about 1/8 turn (or less for tracking). Tighten the set screw in the small hole to LOCK the gear screw (important) before test the mount. Adjust again if needed, but no more than ¼ turn in total. If you feel there is free play between the worm and gear, you may tighten the meshing adjustment plunger to eliminate it.
Appendix D. Firmware Upgrade The firmware in the 8409 hand controller and motor control boards can be upgraded by the customer. Please check iOptron’s website, www.iOptron.com, under the product page or Support Directory.
Appendix E. Computer Control an GEM28 Mount The GEM28 mount can be controlled by a SmartPhone, a Tablet or a computer. It is supported by two types of computer connections: Connect to a computer via USB port on hand controller. The mount can be controlled via ASCOM protocol (Windows OS), or directly by some software, such as Sky Safari (Mac OS) Connect wirelessly via built-in wireless connection. The mount can be controlled via ASCOM protocol (Windows OS), SmartPhone/Tablet and Mac OS wirelessly.
Appendix F.
Messier Catalog This table is licensed under the GNU Free Documentation License.
Named Star 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 Acamar Achernar Achird Acrab Acrux A Acrux B Acubens Adhafera Adhara Adid Australis Ahadi Al Dhanab Al Dhibain Prior Al Kab Al Nair Al Nair al Baten Al Niyat(Sigma) Al Niyat(Tau) Albaldah Albali Albireo Alchiba Alcor Alcyone Aldebaran Alderamin Alfirk Algenib Algenubi Algieba Algiedi Secunda Algol Algorab Alhakim Alhena Alioth Alkaid Alkalurops Alkes Almaaz Al
197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 Proxima Centauri Rasalas Rasalgethi Rasalhague Rastaban Regor Regulus Rigel Rigel Kentaurus A Rigel Kentaurus B Ruchbah Rukbat Rukh Rutilicus Sabik Sadachbia 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 Sadalbari Sadalmelik Sadalsuud Sadr Saiph Sargas Scheat Schedar Seginus Shaula Sheliak Sheratan Sirius Skat Spica Suhail 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 44 Sulafat Syrma Talitha Tania Aust
Modern Constellations No.
Double/Multi Stars No.
No.
No.
No.
IOPTRON TWO YEAR TELESCOPE, MOUNT, AND CONTROLLER WARRANTY A. iOptron warrants your telescope, mount, or controller to be free from defects in materials and workmanship for two years. iOptron will repair or replace such product or part which, upon inspection by iOptron, is found to be defective in materials or workmanship. As a condition to the obligation of iOptron to repair or replace such product, the product must be returned to iOptron together with proof-of-purchase satisfactory to iOptron. B.
