Calgary Fri May 12 16:06:39 MDT 2000 /TRONDSEN
ATT.: SITE CUSTODIAN
The days are getting longer and it is time to shut down the all-sky imagers. Your assistance would be very much appreciated. Keep track of your working hours and charge us as per normal procedure. There are now two imagers that need to be shut down: the old outdoor all-sky imager (Wilbur), and the new imager (Polaris), mounted indoor under the plexiglass dome. The shutdown procedure for Wilbur is explained in a separate communication. What follows are some instructtions for shutting down Polaris.
The imager is located behind the shower curtain on your right hand side as you enter the building.
1. There is a small on/off switch at the back (lower) end of the vertically mounted U-Base that the camera is fixed to. The switch is adjacent to where the mains power (amphenol) connector is located. Throw this switch to the off position. You should hear the various fans go silent. The location of the switch is indicated with a white circle in the first image below. The other two images show the amphenol connector area (110 V mains power) in more detail.
2. The CCD Camera itself must also be switched off. Two cables enter the camera: a co-axial video cable with BNC connector, and another control connector (HiRose) which carries 12VDC power on one of its pins. Simply detach this latter connector (not the BNC connector). You may need to push its shroud slightly and twist, then pull it out and leave it dangling. The arrow in the image below indicates the CCD Camera and the precise location of the power connector.
3. Put the lens-cap on the all-sky camera lens. The lens-cap is a typical (large) black plastic lens-cap, located in the black drawer/bin of the slimmest aluminum crate located in the shower stall. It doesn't snap into place on the lens. Just drop it into place as best as you can (it's not a perfect fit, so it'll still be a bit wiggly).
4. Also located in this drawer/bin is an aluminum shield and an umbrella. We would like to reflect sun-light away from the all-sky camera during summer. Our idea here is to cover the inside of the plexiglass dome with this aluminium shield. You may find that `Da Umbrella' comes in handy for this task? You may have better ideas. This will be a trial and error task. Give it your best shot, and let me know how it went. It is ok for the umbrella to rest against the all-sky camera. The closer the metallic shield gets to the inside dome surface, the better. If possible, the GPS antenna that is clamped to the dome ledge should still be exposed to a clear view of the sky (as we will keep the computer running, and it should preferably receive its GPS time stamps -- not vital, though!)
Thanks and good luck...