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lbaops:lbamar2008:vx014amplog [2015/12/18 16:38] (current)
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 +Mopra has a hybrid polariser which goes at the subreflector and
 +it should be very good. Note that the 2 circular polarisation should have 
 +the same Tsys. If they don't it maybe that the polarisation will need tweeking
 +until they are equal.
 +Polarisation was setup correctly a week earlier. However, the 3cm Rx is having problems and the levels between polars A and B are changing. Hence, the hybrid setting goes wrong and the polarisation purity is terrible!! There is a lot of signal in the cross polars LR and RL even in the fringe fitting. Probably polarisation isolation not better than 10db.
 +This also makes the Tsys values very asymmetric. For Calibration perhaps an average for Ta and Tb may be the best approximation.
 +13:00 UT Recording on ATNF 006B
 +15:59:50 UT Time check. All ok.
lbaops/lbamar2008/vx014amplog.txt · Last modified: 2015/12/18 16:38 (external edit)