... The platform will move because of temperature, tiedown tensions, weight distribution, and oscillations. We can measure the platform motion using theodolites (surveys), tilt sensors in the dome, distomats, tiedown tension, and pointing error. ... Tilt sensor measurements(from dome) . ... 020729:Platform tilt while td tracking on (do the td's move together). 0108xx: Horizontal offset of platform relative to AO9 monument. 010413: platform motion as we pull uniformily on the 3 tiedowns. <- page up . ...

... 2.3 Data acquisition Spectra generated by the Multibeam correlator contain the usual structure seen in spectra from other H i instruments: a bandpass spectrum which is the sum of the sky , ground and receiver temperatures multiplied by the product of the filters in the receiver chain; superimposed on this is a noise ... Note also that sources extended much beyond ,40 arcmin can be imaged poorly in HIPASS images because of the bandpass sidelobe effect described in Section 3.3. ...