Bare multiplexer (MUX) from Raytheon. This unit is electrically identical to the science grade detector, but has no infrared sensitive layer. This unit was used to verify electrical connections and array readout electrical operations.
Zoom of MUX. The physical size is about 1.3x1.3" square. The silicon, light sensitive, portion is gray, the mounting ceramic substrate is gold plated, and the bonding pads are gold. A couple of the 0.001" gold bond wires can just be seen connecting the silicon wafer to the bond pads.
The monster duct. The air-cooled CTI 1020 helium compressor proved to be a wonderful room warmer. Perhaps more than we wanted. We constructed a large ducting system to try to move the hot air exiting the compressor out the nearby window. It sort of worked, but ended up obstructing the airflow from the compressor so much that we later removed the ducting and just allowed the lab to creep up beyond 100 degrees F.
We tried augmenting the ducting with a fore fan and later an aft fan to move air over the compressor cooling coils. This never quite worked adequately, as the exit temperature stayed above 110 degrees F.
Electronics test bench, while examining stepper motors and STP100 controllers.
Filter wheel under construction in Miltronics mill at BU SIF.
Filter wheel detail. The pockets cut for each filter location were designed to accomodate and locate the outer lip for each filter cell. In the bottom of each filter location is a set of holes to hold a pin to locate the filter cell.
Completed filter wheel (this is FW3). Ten filter locations with ten encoder positions are shown in this light-weighted wheel. The outermost surface is only some 0.100" thick. After machining, this wheel was sent out for thermal stress relief, bead blasting, and black anodizing.
Detail, showing slot for filter cell lip, holes for locating pin, and twin tapped holes on raised block to hold the encoder magnet block for each filter.
Closer detail to show slot and holes for alignment pin.
Filter wheel and filter wheel hub drawings on wall at BU SIF. Mimir was one of the most complex and detailed projects fabricated in the SIF.
G10 collar, already epoxied into Big Ben warm bulkhead, now grooved and drilled in preparation for being epoxied into cold bulkhead.
Detail of G10 collar, showing grooves and holes. Both were designed to capture/flow epoxy around and inside the cold bulkhead groove to ensure excellent adhesion and high mechanical strength.
Big Ben and G10 collar being prepped for epoxying to the cold bulkhead.
LN2 precool ring and stainless steel corrigated hoses. The ring was an aluminum ring, filled with ball bearings. The aluminum to stainless transition pieces were vendor supplied, spun pieces. These were welded into the aluminum ring and into the baffle tubes.
Another view. Note that the LN2 ring is split and the transitions attached at the split ends.
Detail, showing the aluminum to stainless steel transition pieces and the gap in the aluminum ring.
Wire-wrap prototype I/O board to host the STP100 stepper motor controller board and provide more motor/sensor control
Testing the prototype I/O board, with STP100 stepper motor driver board, and stepper motor jig (as configured for the cryovac chamber).