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HOBYM Observatory Crux 320HD Harmonic Drive Mount

HOBYM Observatory Crux 320HD Harmonic Drive Mount
HOBYM Observatory Crux 320HD Harmonic Drive MountHOBYM Observatory Crux 320HD Harmonic Drive MountHOBYM Observatory Crux 320HD Harmonic Drive MountHOBYM Observatory Crux 320HD Harmonic Drive MountHOBYM Observatory Crux 320HD Harmonic Drive Mount
Price:  £10,999.00(Inc. 20% VAT)

Product Code:  CRUX320
Brand:  HOBYM Observatory



Special order item, Please contact us for an ETA

HOBYM Observatory

Crux mounts feature Harmonic Drive / Strain Wave Gear Tecnology. This tecnology gives Crux mounts the following advantages over traditional drive systems for astronomy applications;

 - The mounts have zero backlash and therefore pointing and guiding can be very accurate

 - They have very high torque. This makes it ideal your use with all loads. For instance the length of a refractor normally requires a much more powerful mount than a typical weight capacity suggests. The load limits for Crux mounts are for all types of telescopes and also for imaging

 - The motor is very compact and therefore allows a small form factor, resulting in less bulk and weight.

 - Harmonic Drive motors are very responsive and therefore react instantly to guiding commands. When combined with the zero backlash this allows for extremley accurate tracking. There is none of the high frequency oscillation normally associated with traditional drive systems.

 - The high torque of the motor permits use without a counterweight, further reducing the overall weight. If a counterweight is added, the load capacity can be increased significantly. Note that this counterweight is not used to balance the telescope in the normal way. It is simply helping the drive system and making the load safer.

Please see the short video below for an explanation of how the Harmonic Drive system works.

The Crux 320HD is a highly accurate, medium capacity mount (60kg) that is compact and weighs only 25kg. It is a fully GoTo enabled system which includes a 12000+ object database. Without any counterweight the mount has a load capacity of 23kg, enough for a significantly sized telescope. By adding a 15kg of counterweight, the maximum capacity is increased to 60kg. This capacity is rated for imaging and for difficult loads like a large and long refractor
The '320HD', as with all Crux mounts is provided with a mounting point for a QHY Polemaster. No adapter is needed. This makes polar alignment using the built in Altitude and Azimuth controls very simple.
Supplied with all Crux Mounts is the Titan TCS Controller. This provides GoTo functionality and all other mount control and connectivity. It is based on the LX200 protocol and is therefore fully ASCOM and INDI compliant. It also features wireless connectivity in the form of Bluetooth, with WiFi being added shortly. Thus is allows easy integration with Tablet applications such as Sky Safari.
One significant function of the Crux mount and TCS Controller is PEC training. This is where, using a guide system (like PHD2), the drive system is trained. This, once completed permanently (unless reset by the user) lowers the PE of the mount to typically +/- 3 arc seconds for the 320HD. This enhanced error can then be combined with guiding leading to extremely low PE. Potentially as low as 0.1 arc sec. As part of our service, we PEC train each mount before delivery so you receive a mount that is capable of operating at its best, straight out of the box. A copy of the PE test data is also provided.

General Specifications - Crux 320HD
Type German Equatorial
Azimuth Adjustment Range +/- 15°
Altitude Adjustment Range 20 to 70°
Weight (excl counterweight) 25kg
Optional Counterweight 5.0kg
Max Load (No Counterweight) 23.0kg
Max Load (with 15.0kg Weight) 60.0kg
Power Source 12V DC
Telescope Mounting Format 4xM10 or 4xM8 35mm Spacing
Polar Alignment Support Polemaster Mounting
Dimensions 500mm x 431mm x 220mm (at 32° Alt)
Backlash Zero
PE Error after PEC Training +/- 3 arc sec (after PEC)
High Speed Slewing x600
Titan TCS Controller  
Size 83x87x36mm
Input Power 12-30V DC
Protocol LX200
Database NGC,IC,Messier, Planet 12000+ Object
Power Consumption (Tracking) 12V 0.3-0.5A
Power Consumption (Max Slew) 12V 1.5-2.0A
Wireless Connectivity Bluetooth (WiFi to be added)
Interface RS232 / USB / ST4 Guide

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Telephone: 01353 776199 or 07990 646466

2 Rosemary Lane, Sutton nr. Ely, Cambridgeshire, CB6 2NZ
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