au.getFrequenciesFromASDM(asdm, spws=None, minnumchan=128)
CASA <11>: au.getFrequenciesFromASDM('uid___A002_Xa2ce2e_X54b',spws=[9,11,13,15]) Out[11]: [653151500000.1, 655026500000.1, 656901500000.1, 658776500000.1]