[Moon] Is it possible to use Absolute and Incremental Encoders tracking moon with an antenna.

[Darrell]

Hi Anders & All;

Anders I believe you are running this into the VK3UM Board, and 
i  believe you should increase the Ratio of Encoder to Mast 
travel...........I suggest 10:1 if possible......this would give you 
20,000 counts is 360Deg, or 55.55556 per Degree of motion.

This will decrease your error by a factor of 10 as well.......but not 
quite clear on which Board you are using????  It apparently is not 
sensing the direction of counts........if the Dish move right, then 
back left the pulses should be Added, then immediately Subtracted, 
regardless of how far, or how little is moves.

NOTE: I am not trying to promote or Sell you a Product.

Regards & GL, Darrell

At 09:01 AM 2/5/2007, Anders, LA8LF wrote:
>Hello,
>
>Untill now I have used my own constructed pulse encoders on the AZ 
>and EL motor shafts to create pulses for my modem. Yesterday I 
>installed US Digital type H3-2000HS  inclinometer encoders that 
>gives 2000 pulses/360 deg. rotation, i.e. 5.55555 pulses/deg movement.
>Between AZ motor and 90 mm. AZ mast tube there is approx. 1 deg. 
>free run (backlash). No backlash between the 130 Kg. commercial 3 
>phase 230V driven EL-screw but the 700 Kg. 4.65M solid dish moves 
>slightle even with slightest wind. Any movement of the
>dish greater than 0.2 deg. adds false counts in the tracking mode, 
>both AZ and EL due to movement of AZ free move (backlash)  and 
>slight wiggleing of the dish in EL.  The EL encoder uses a 0.2 Kg. 
>counterweight always in vertival pos.I have seen pictures of numerous
>installed encoders the same way as mine, but honestly do not 
>understand how these installations can cope with the slightest wind! 
>And we will have increasing wind in numbers and force in the coming 
>years. I could go back to using my own made encoder mounted on the shaft
>coming out on the back of my 3 phase 230V AC motor, but this is more 
>difficult to do on the EL motor as it takes 45 minutes to travel 
>from 15 to 55 deg. EL. That is a tremendous number of motor 
>rotations and a reduction gear of some 300:1 needed to be mounted at 
>the motor shaft coming out at the back end of the motor.
>
>Does anyone have a working solution for using commercial encoders 
>like mine mounted on the AZ mast tube (those who faces a small 
>backlash in their motor/gear system) and non-motor mounted EL encoders?
>
>73 de
>Anders
>
><mailto:Anders at LA8LF.com>Anders at LA8LF.com
>www.la8lf.com
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