Sometimes the connections trip you up. We’ve spent the last several days trying to get our unruly Gorgon of signal cables to lie straight and carry signals cleanly. Each of our ten detectors has forty channels, so there are plenty of chances to get our wires crossed. Our signal cables are great–long ribbon cables, each strand of which is actually a coaxial wire with two conductors. The cables are accordingly much lighter and more compact than individual wires would be, but they are rather delicate. Routing them safely through the twists and bends of the journey from the cryostat, around the cradle, through a hole into the electronics bay, and to the appropriate board in the right card cage is a challenge. We’re also finding a few of the connectors are showing signs of fatigue, introducing flakiness into some channels. Replacing bad cables with our few spares can aggravate that fatigue, though. As usual there’s a balancing act between pushing for ideal performance and avoiding causing larger problems in solving smaller ones.
Still, the system is taking shape. The third payload, HERO, has arrived with their gear, so the hangar is now quite full. We’re all sharing a single crane along the centerline of the building, so we put the gondola on our cart for now to allow them to use that space to build. We also started up the flight computer and are now running the system through it. Since programming the flight software was my main responsibility last flight, it was very satisfying for me to see the flight computer running nicely again. I also connected our differential GPS antennas, which seem to be functioning just fine.
Tomorrow, a rest day for most of us. Soon we’ll be calibrating and testing the system with radioactive sources. Monday also brings our Flight Requirements meeting with CSBF, where we’ll discuss our altitude and duration targets for the flight.