Planning Spectral Observations

Surface Brightness Masers - resolved

often at <1kpc HI absorption -

background 106K

Resolution Global? Fill in e.g. MERLIN?

Check archivesNGC4261 van Langevelde et al.

MERLIN archivewww.merlin.ac.uk/archive/

EVN archiveVL(B)A archivesvia respectiveweb pages

Line frequency, width, VVLSR,radLSR,rad

RFI avoidanceReceivers, filters & No. IF's available

Correlator capacity NchNpolNBNIF/ <t max

ResolutionHA coverage

Sensitivity How long?

Calibrators observe more than once! Delay Bandpass - bright! Fringe &/or phase Polarisation

leakage Polarisation angle

Can be the same source(s)

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