Telescope parts: Horns and the rotary floor.

Horns:

• 10 receiver horns/dipoles are mounted on the rotary floor.
• The receivers cover 327 Mhz to 10 Ghz.

• Can position each of the 10 feeds above the tertiary focus.
• It is a drive system that can point to sub arcsecond accuracy.
• Also used to switch rapidly between the sband transmit and receive horns (12 deg/sec).
• The mapping of feed motion to motion on the sky is:
• 13.88 arcsec/cm perpendicular to za direction. This is the turret rotation direction. 1 turret degree=3.24 cm
• 17.04 arcsec/cm along the za direction.
• We have a tilt sensor mounted on the rotary floor at turret = 75 degrees. It is used to measure tilts (pitch, roll) of the dome.