US SKA TDP Antenna Specification Structural Mechanical Rev B US SKA Antenna Working Group Meeting May 7, 2009, Los Angeles, California Matt Fleming Contributions from Jack Welch Roger Schultz Sandy Weinreb Gerry Harp

TDP AWG meeting, Los Angeles, Matt Fleming slide ‹#› of 7 TDP Antenna Specification Structural Mechanical Portion o This presentation contains the same material shown in the Antenna Specification document already distributed. o Metal Shell reflector for symmetric or offset. Design for survival then improve to spec goals as cost allows. o Specs presented in 3 sections. ( grouped ) Summary section. ( major items not related to environment )( page 3 ) Operational environments. ( Precision, standard, degraded )( page 4 ) Other items of interest. ( page 5 ) o Suggestions generated here will be included in a final version. take notes & turn them in.

TDP AWG meeting, Los Angeles, Matt Fleming slide ‹#› of 7 Document page 3, top half Rev B Section 1 of 3, offset

TDP AWG meeting, Los Angeles, Matt Fleming slide ‹#› of 7 Document page 3, bottom half TDP Antenna Summary Specs, Rev B Section 1 of 3, continued

TDP AWG meeting, Los Angeles, Matt Fleming slide ‹#› of 7 Document page 4, cropped Section 2 of 3

TDP AWG meeting, Los Angeles, Matt Fleming slide ‹#› of 7 Document page 5 cropped

Some suggestions so far Offset primaries defined by f/D parent? Baselines over time. ( Correlated & uncorrelated errors ) Level tolerance pedestal & az bearing ( across the continent ) Tolerance, az – el axis offset & perpendicularity. ( mfg variance ) Tolerance, el – radio axis offset & perpendicularity. Temperature stability of air supply. TDP AWG meeting, Los Angeles, Matt Fleming slide ‹#› of 7