Autoguide

The computerized altazimuth newtonian system can accept autoguider input.

The autoguider needs to supply a relay for each direction, or, a +5 VDC TTL signal for each direction, or, a serial connection sending LX200 protocol commands.

If using a relay box, wire the interface circuit such that when a relay closes,  a +5VDC TTL signal is supplied as follows:
If using a control signal, tie the control signals so that the control signal going to logical high raises the input voltage to a +5VDC level as follows:

(this scheme mirrors the four direction buttons on the hand paddle)
 

  • up or north: to pin 13 of the parallel port,
  • down or south: to pin 12 of the parallel port,
  • left or counterclockwise: to pin 10 of the parallel port,
  • right or clockwise: to pins 13 and 12 of the parallel port.

  •  

    To operate:

  • 1. Put the telescope control program hand paddle mode into one of the guide modes.  Set the speed of the guiding corrections by adjusting the microstepping guide speed.
  • 2. Orient the autoguider by rotating it so that the autoguider's up and down correspond to the telescope's autoguider.
  • 3. Calibrate the autoguider.
  • 4. Initiate guide corrections by the telescope control program by momentarily flipping the hand paddle mode switch to the left and then center the switch.
  • 5. Start the autoguider.
  • All guide functionality continues to exist with the autoguider on.  For instance, in guide+stay mode, flipping the hand paddle mode switch momentarily to the right will calculate drift, and null the telescope's drift.  Immediately re-initiate telescope control program guiding by momentarily flipping the hand paddle mode switch to the left and then center the switch.  In guide+record mode, a record is kept of the autoguider's corrections.

    The hand paddle can continue to be used.  Pressing a direction button will add its guiding correction to the autoguider.
     

    Guide arrangements include:

  • piggyback guide scope
  • off-axis guider
  • intercept guider
  • built-in guider chip ala ST7, ST8

  • return to top
  • continue onto 'Configuring the Software'

  • ...by Mel Bartels