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2017/04/15 (Saturday)

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Setup: DIB1/3/4 → 3.2 MHz filters 3/1/2 → cable 3/1/2 → gender changer 3/1/2 → DCRC55(1)/33(2)/X(4)
1200 Fill LN2 cold trap bath.
1232 Tower/MC/Coldplate = 33.3/30.8/194 mK, Still = 1.3 K / 0.120 mbar, G1/G2 = 249/238 mbar, 1K Pot = 1.689 K / 28 mbar. MB = 67.8%. Boil off rate: close to slow mode (predicted level: 69.7%).
1327 Complete IbIs on DCRC4PB/S2PF. Was able to get a full curve, but had to move slowly down the transition to keep from falling into sc early. I also noticed a discontinuity in the curve when stepping down by 0.25uA. When going from Ib = xxx.25 to xxx.0, (corrected values are generally something like xxx.26 and xxx.01) the Vout value at xxx.0 would rarely fall as much as expected given the surrounding curve. This can be seen in the plot below.

1200 It has been observed that DCRCX cannot have its FE Gain above ~4-5 without introducing high frequency noise. Perhaps this is due to the low-pass filter in the feedback loop? Measuring R124 (which sets the cutoff frequency for PA) on DCRC1, DCRC3, and DCRCX all give 3.3kΩ.
1430 Complete IbIs on DCRC1PA/S1PE.

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