SDO Weekly Report for August 6, 2004

The Project has agreed with the recommendations of the Attitude Control
System (ACS) and Systems teams to proceed with a CCR to add a Digital
Sun Sensor to the baseline SDO ACS design.  The rationale is that, given
the current range of performance of star tracker components that are
being considered the ACS design is marginal in some calibration
situations.

The Project Management Information System (MIS) administrators continue
a series of meetings with our new programmers to capture the
requirements for the MIS enhancements, and to storyboard the MIS
system.  Implementation is scheduled to begin this month.  SDO's CM
system received high marks from the ISO auditor last week.

SDO provided an updated reduced thermal model for the spacecraft to HMI
and AIA this week, and an updated finite element model of HMI was
provided to the SDO. Encoder assemblies are being prepared for the
Hollow Core Motor life test. Vision Composites is making good progress
on the HMI structural model and expects to deliver it by September 17,
2004. HMI and AIA participated in a pointing, alignment, and jitter
working group this week with the project, and are preparing for the
interface working group to be held at LMSAL next week.

The Ground System received notification that the Data Distribution
System's IN-SNEC Front End Processor (FEP) did arrive at Dulles Airport
from France. It will be picked-up and shipped to building 16 tomorrow or
Monday 9Aug04. This gives the Project two FEPs. Ground system personnel
are now ready to support C&DH and other related testing. Also, the RRCP
(Range-Receive-Command Processor) RFP went out to industry this week.
The RRCP unit is needed prior to antenna vendor selection and is also
needed for ground station testing.

The ACS Inertial Reference Unit, Star Tracker and Reaction Wheel
Assembly RFOs were released. The Propulsion System Pressure Regulator
RFO was also released. A Project decision was made to baseline a Digital
Sun Sensor in the ACS design. Progress was made with testing of the
Ka-Band SSPA Breadboard. Completion of SSPA testing is a key milestone
that will help to retire risk associated with in-house development of a
Ka-Band transmitter. The Power System Electronics (PSE) Subsystem Data
Node (SDN) Core Breadboard was completed.  The PSE Engineering Test Unit
(ETU) Backplane is in checking(before being sent out for fabrication);
the ETU Output Module, ETU Battery Module, and ETU Solar Array Module
are currently at Northrup-Grumman either in, or awaiting, layout.
Layout continued for the C&DH Ka Comm Card, BMC, and DC/DC Breadboards.
Fabrication of the ACS Reaction Wheel Interface Breadboard was completed.

The SDN breadboard and daughter card, along with software, diagnostics
and S/W development tools, were delivered to EVE/LASP this week.
According to all reports, the delivery and integration into the EVE
environment went very well.

--
Liz Citrin
SDO Project Manager
301-286-1222
FAX 301-286-0214
Cell 410-241-0503