Parallactic observatory mount with servo motors and CP4 control box (keypad optional), recommended for refractors up to 250 mm and RC optics with 18" to 20" aperture.
The GTO-1600 is the successor to the now legendary GTO-1200 from Astro-Physics. It was voted "Hot Product" of the year by Sky&Telescope in 2013. In 2017, the new CTOCP4 motor controller was also voted "Hot Product" of the year.
The engineers at Astro-Physics now have more than 30 years of technical expertise in designing and manufacturing mounts with maximum load capacity, high-precision tracking and GoTo performance, while keeping the weight to a minimum.
After more than 12 years of successful production of the GTO-1200, the engineers at Astro-Physics decided that the time was ripe for an improved and more robust successor to the GTO-1200 – the result: the GTO 1600.
As with the GTO-1200, the pole block with RA axis and DEC axis block can be separated for easier assembly and transport. The connection is made via a CNC-milled dovetail guide. The RA block weighs 29 kilograms and the DEC block 18 kilograms. The GTO-1600 is designed for stationary installation.
The most important innovation is the auto-compensating motor gearboxes: Astro-Physics has radically revised and redesigned the drive technology of the mounts. All Astro-Physics mounts, including the GTO-1600, now feature auto-compensating motor gearboxes on both the RA and DEC axes. These offer great advantages for astrophotography as well as for visual observation.
Backlash problems are also largely a thing of the past. When adjusting with tension/pressure screws, the problem was always finding the optimal setting. If the distance between the worm and the worm wheel is too large, the backlash is much too high; if the distance is too small, there is a risk of the drive blocking, e.g. due to temperature fluctuations. Thanks to the new design, the worm and worm wheel are always in optimal engagement.
To prevent damage to the drives during transport, the entire motor/screw block can be completely disengaged using a small lever and re-engaged just as easily after transport.
Even after years of use, and even under very intensive use, the drive worm always presses optimally into the worm wheel when material wear occurs. In addition, new steel alloys with extremely low wear are used for worm production – not unimportant for automated observations, where the telescope is frequently swivelled back and forth at high speeds in GoTo mode.
The concentricity (PE - periodic error) of EVERY drive worm is measured with the PemPro software before delivery of the mount, and the resulting compensation is stored in the CPC control box, so that the PEC function (periodic error compensation) is immediately available to you as the observer. This compensates for 90% of the periodic error - not unimportant for photographic observations with shorter exposure times WITHOUT guiding.
GTO Servo Drive System Specifications:
- Schweizer DC servo motors in closed aluminium housings with high torque
- Motor encoder with 2000 steps per revolution, resulting in an effective resolution of 0.05 arc seconds per step.
- Motor reduction gear 57.6:1 with finely toothed precision gears with large diameters for high power transmission
- Periodic error: 5 arc seconds peak-to-peak (+/- 2.5 arc seconds) or less during one worm revolution (6.4 minutes) before each error correction (PEC)
- Maximum positioning speed: 5 degrees/second (1200x tracking speed)
Included in delivery:
- Pole block with RA/DE axis cross
- GTO servo motors Control box
- Stainless steel counterweight bar with safety screw
- RA/DE Y-cable for connecting the GTO control box to the drive motors
- Power cable set for GTO-CP4, incl. 1.8 m (6') cable with PowerPole connector, 45 cm (18") cable with cigarette lighter plug and 45 cm (18") cable with ring cable lug (power supply operation)
- 4.5 m (15') serial extension cable
- 1/4-20 inch knurled screw set
- Inch hex key set
- CD with PEMPro v2 software and PulseGuide software by Ray Gralak, Sirius Imaging, and PDF user manual for GTO-1600 and GTO Keypad
- Warranty/registration card
- ASCOM driver (available for download)
