... Proposing for VLBI Time at Arecibo . ... Documentation (Field System, VLBA4 terminal, Mark 5 system) . ... In 2001, the Arecibo Observatory received its hybrid VLBA-MARK IV (VLBA4) data acquisition system, and currently NAIC commits Arecibo to support VLBI observing up to a maximum of 4% of the 305-m's observing time. ... Tracking Time (h:mm) . ... The inclusion of the 305-m Arecibo radio telescope can dramatically boost the sensitivity of VLBI observations, even with its limited source tracking...

... 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. ...