The linelength system monitors changes in the delays through the optical fibers to the antennas. The delays vary as the fibers change temperature. The delay variations are small, typically less than 0.05 nsec on time scales of hours, but they are enough to cause significant phase drifts of the local oscillators on the receivers. Since these changes are measured accurately by the linelength system, the corrections should be applied.
Phase corrections from the linelength system are stored in the Miriad uv variable phasem1, which is an antenna based variable.
To apply the linelength corrections, use the Miriad program linecal, which writes an antenna based calibration table in the dataset that can be applied. However, don't expect perfection - the linelength system cannot correct for differences in the thermal expansion of the antenna structure (particularly BIMA vs OVRO) or for changes in the temperature of the phaselock electronics. Schematically we will do:
linecal vis=$data gpplt vis=$data yaxis=phase nxy=5,3 device=/xs options=wrap uvcat vis=$data out=$data.lc
Here the gpplt commands displays the actual phase corrections that are going to applied in uvcat. You might see many wraps, but remember it is only the differences in phases that matter, these are antenna based phases.
TODO: careful with select=-source(noise)