SPP Fluxgate MAG input to FIELDS Quarterly Review – 7/18/2013

1. SPP Fluxgate MAG input to FIELDS Quarterly Review – 7/18/2013 Bob MacDowall, Ron Oliversen, Dave Sheppard, Scott Murphy, Jim Odom, Jack Connerney

2. SPP MAG Status • Some scheduled MAG activities have slipped; however, we are now in receipt of most information (ICDs, etc.) and materials needed, and we have a clear understanding of the path to PDR. • The AC Heater (ACHE) PCBs have been laid out and procured. They will arrive next week and will be populated and tested ASAP. • Macor bobbins and other procurements are nearing completion, facilitating the build up of the ETUs. • Significant progress with thermal modeling for the MAG sensors has allowed a better understanding of constraints and mitigations of the thermal range; we are interested in results from Gail Martin on any additional power available. • Thermal testing (-50 to +50 C) of GSE sensor (Macor base) is currently being conducted in a non-windowed thermal vacuum chamber (see photo on next slide). First goal is to determine how fast we can cycle. • Design of a composite base for the ETU MAG sensors is completed. • Ongoing concerns include: MAG sensor placement on boom relative to spacecraft, power, etc., available to increase low end MAG sensor temperature, alignment error budget numbers, boom harness plan, conclusion of L4 requirements & ICDs

3. MAG thermal vacuum chamber #1 • Chamber shown at right permits operating over a large temperature range (order of -100 to +100 C) at < 10^-5 torr. (Same aluminum cylinder is also the “insert” for the windowed TV chambers.) • Currently instrumented (8 thermistors) and being used to determine the rate at which we can cycle the MAG “GSE” sensor temperature, which has consequences for all future thermal testing. • Since chamber has no windows, the sensor alignment inside chamber cannot be determined, i.e., no calibration over temperature. • We can calibrate zero levels, etc., before and after thermal cycling. If they do not change, then we can conclude that calibration as a function of temperature will be possible – adequate for PDR. TVC #1 working in GSFC Mag Lab.