2019/04/07 (Sunday)

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Setup	DIB1/3/4 → 3.2 MHz filters 2/3/1 → cable 3/1/2 → gender changer 3/?/2 → HVConn 1/3/2 → HV 1/2 → DCRCX(4)/DCRC50(3) DCRC33(2) → 1kV power supply → HV input Lead poly shield is erected, N/E/W walls complete, no poly or lead on S wall.
0615	Tower = 39.1 mK
0620	Apply 10 uW of power to MC heater
0630	tower = 56.5 mK. Looks like it might flatten out at 57 or 58 mK
	We will see whether a higher base temperature gives us better QET performance. We tried this in Run 61. We will need to adjust the QET biases downward (by maybe 50 uA?) to get to good points in transition. The hope is that the oscillations will be much lower in amplitude.
0640	Tower = 56.7±0.1 mK, looks like it's flat here (a little wiggly)
1509	Tower/MC/Coldplate = 56.5/48.8/189 mK, Still = 1.71±0.15 K / 0.150 mbar, G1/G2 = 310/296 mbar, 1K Pot = 1.78 K / 13 mbar. MB = 24.1%
1518	Commence LHe transfer, MB = 24.1%
1520	Fill LN2 cold trap full.
1538	Tower = 59.2 mK and rising slowly
1543	Tower = 61.0 mK and still rising. Maybe we pushed a channel into a bad state somehow? Set all QET biases to 0. Heating slows for a minute, then resumes. Probably due to the transfer then.
1550	Tower starts to flatten out at 61.9 mK
1555	Cease LHe transfer, MB = 91.7%
1600	Tower = 60.5 mK and cooling. Snap and re-apply QET biases.
1615	Tower = 59.4 mK and cooling slowly.
1616	Got all channels in transition with (mostly) lowered QET biases. DCRC4/3 QET biases = (390/350/390)/(500/410/450) uA. DCRC3 pC is at a higher value than before, but it is now above the oscillation region. There doesn't seem to be any room below it now. Not sure how these values will hold up as the tower continues to cool back down, but it's a start.

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