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Feb 22 Drift Scan Concept Test:

It is raining with solid clouds and fog.

Long story short: we started out with the wrong receiver (Q band) at focus and didn't notice. The crappy focus and ptg were just to be expected with the rain. Barry noticed the occasional "rx not in position" error but we didn't want to stop to double check (this was after the peak focus). Eventually double checked and fixed it.

About then we also had noticed that all the 31 GHz channels in the CCB were saturated. But the other channels were around 7000 counts (meaning, you are not at focus!). ~mshepherd/bin/ccb_test_sample_stats showed all the samples on 31 ghz channels were reading zero. I noticed the LO power in the Rx was nonzero and wondered if this might contribute. We played with the siwtches while watdching the CCB differencedc power in 31 ghz and indeed, we saw an effect!!

We also had vdef/vframe omission problems, not being carried over from previous obvserver-- fixed in scripts.

Finally we note that S4 is generally just not getting set by my killo scripts (again: LO power in RX not zero) but the other switches are getting set.

Dummy scan around 4:45 to clear astrid hang-up

Successful el ptg/focus at 6:30. After sunrise, cleared up and Total Power looks flat and good. Probably have ~1 hr of pretty good data.

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