REMOVE THE DETECTOR BOX
Here you will start to get close to delicate parts.
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Be well with the terminology:
Detector box: the aluminum light tight box that houses the detector
card.
Cross-brace: the G10 (green plastic) piece on which the det.
box rests, and which is tied to the bottom dewar plate by 4 small screws.
The cross brace also has a DE9 and a DA15 connector in it.
Cu-C wires: the VERY THIN copper-constantan wires that go to
the detector card. There are 4 sets: from back of DE9 to detector card
(red), from back of DA15 to detector card (red), 2 (purple) ouputs from
detector card to amplifier input (near the front part of the dewar-front
= direction of incoming light-) and 2 unused outputs (red, I think) from
an unused quadrant.
Snout: the cylindrical nose attached to the box, from which
the light enters.
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Disconnect the DE9 and DA15 connectors FROM THE FRONT. DO NOT PULL ON THE
WIRES.
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Disconnect the 2 purple cu-c wires from the amp input: use small pliers
to gently hold on to the gold pin at the wire end, and gently pull it up.
Remember where you pull them from since they will need to be put back at
the same place. They are lebelled though. Also "disconnect" the 2 spare
wires from the unused quadrant from the dummy socket that is glued to the
bottom plate.
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Unscrew the cross-brace from the dewar bottom plate. Even tough the bottom
shield is in the way, you can do this with a long Allen drive and going
in at an angle.
Now, the three things you disconnected in (3-1) and (3-2) will be sort
of in the way for the next step. Be careful and creative to complete it
without having a wire get caught someplace and ripped.
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The objective is to take out the detector box, for which it needs to be
lifted through the rectangular opening in the lower shield. As you do this,
the cross-brace will of course come along, as will the 4 output cu-c wires,
and the cold straps.
The most important things here are to watch, as you lift up the box, that
the 4 loose cu-c wires don't get caught and break, and not to damage the
2 sets of red cu-c wires at the back of the DE9 and DA15 connectors in
the cross-brace as they pass trough the rectangular opening. Another complication
is that the snout is also attached to the box and it needs to clear the
circular opening at the front of the shield, but that's not too hard.
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Set the assembly box+snout+cross-brace in a clean area, on top of a paper
towel. From now on you will only work on this. I find it most comfortable
to let the assembly rest on the cross-brace legs and the tip of the snout,
tilted forward, with the thin red wires and the back of the box facing
you.
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