Spectroscopy, Gecko: The Coudé f/4 Spectrograph
Gecko: Setup of
Triplet (Transfer) Lens
When Using the Coude Train
- gain on the Slit Camera is down,
- gain on the Autoguider is down, and
- EM shutter is closed.
In the outer Coude room:
Get me back to the Secret page!
- Put the Power Supply ON (back of the room,
power supply is on a shelf).
- Cover M7, ie, check and note the XY
measurements of the mask, tilt the mask, and then cover M7.
- Remove flange + 4 cap screws under the lens
(above the M7) - Be extra-careful not to drop any screw!
- Use the ladder, open the access door to the
- Use the switch to unlock the mechanism -
something will start moving, but it does not have to go all the way.
- Use the other switch to rotate to the desired
lens, then backup a little to have some play.
- Look from under the lens, center it by hand
by pushing on the silver ring around the lens (this is easier if there
is some backlash).
- Put back the flange + 4 screws - the flange
should go in relatively easily - if not, re-adjust the silver ring.
- Lock the mechanism using the switch - keep
the thing moving until the sound of the motor changes.
- Close the access door.
- Put the power supply to OFF.
- Uncover M7.
- Note which lens is now installed.
Send comments to: Nadine Manset
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