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2017/12/15 (Friday)

	Setup: DIB1/3/4 → SL 27/19/20 → 3.2 MHz filters → cables 2,1,3 → HV board inputs 1,3,2 → HV board outputs 1,2 → DCRC55(1)/50(3). DCRC4 → HV power supply.
0615	HV = 69.91 V, V_leak = 2.39 mV
0615	Tower = 21.7 mK
0621	Start random rate scan sequence rand_rate_scan.msl to take 3 minutes of randoms at 60,80,100,120,140,160,180 Hz with ChargeWaveFormLengths/PhononWaveFormLengths = 64/4096 (half the current standards) on DCRCs 1,3,4
	The read rate kept up with the randoms rate up to the 100 Hz series. After that it saturated at around 110 Hz. When we had the standard trace lengths it saturated around 65 Hz - you may have expected the saturation point to be about double that in this case, but it's only about 70% higher.
0740	Dial HV bias down to 0 V using changeHV_70_0.msl
0800	Flash detector with DCRC1,3 LEDs for 50 s (typed in 50 by mistake, meant to do 30)
0930	Oops - the flashing is still going, 1.5 hours after starting. Must not have entered “0.01” as the duration. Stop flash sequence. Tower was at 600 mK, now cooling.
0940	Tower still stuck around 400 mK so something in the sequence didn't finish, probably stopped in the middle of a flash. Re-run the flash-and-flash tool with a 5-second flash. Now the tower is cooling to base.
1025	Tower = 33 mK. It's taking a while to cool to base after that long bake.
1025	Noticed that Enable15VPower was on on DCRC1,3,4. Turned it off - now Tower is cooling much more quickly. Turning it off on DCRC4 apparently also turned off the HV power supply - so I reenabled it on DCRC4, and now the power supply is back on.
1425	Tower/MC/Coldplate = 21.7/25.5/151 mK, Still = 1.2 K / 0.100 mbar, G1/G2 = 238/225 mbar, 1K Pot = 1.62 K / 26 mbar, MB = 22.9%
1430	Fill LN2 cold trap bath.
1430	Dial HV up to 70 V with 15% 5-minute prebias, using changeHV_0_70_preBias15_5.msl
1520	HV = 69.89 V, V_leak = 2.60 mV
	Pulse-flipping: we'll experiment with reversing the QET bias of half the channels, so that if there is correlated external noise, when they are summed it will cancel.
1550	Reverse biases of three channels:

DCRC chan	Det chan	QB before	QB after
DCRC1pA	Side1pE	480	-500
DCRC3pB	Side1pA	480	-480
DCRC3pD	Side1pF	490	-490

	note that with DCRC1pA we didn't put it to quite the same magnitude. That's because it seemed to be in the oscillatory region. This channel has a weak-ish oscillation regime at a mid-high point in transition - we avoided it by going a bit higher. It's possible the QET bias is offset so that the transition is shifted a bit. So we pushed it to -500.
1606	Begin LHe transfer @ 20.0%
1647	End transfer @ 89.6%
1705	Start sequence of 3 60-minute background data series at HV = 70V, Driver Gains = 2x, QET biases = (-500/360/440)/(-480/380/-490) uA, Front-End Gains = 10/5 on DCRC1/3, 1000 initial randoms, trigger on DCRC3pC threshold 13.
2110	Dial HV bias down to 0 V using changeHV_70_0.msl
2125	Flash detector with DCRC1,3 LEDs for 30 s
2210	Dial HV up to 70 V with 15% 5-minute prebias, using changeHV_0_70_preBias15_5.msl
2225	HV = 69.86 V, V_leak = 2.57 mV
2225	Tower = 21.6 mK
2227	Start sequence of 4 60-minute background data series at HV = 70V, Driver Gains = 2x, QET biases = (-500/360/440)/(-480/380/-490) uA, Front-End Gains = 10/5 on DCRC1/3, 1000 initial randoms, trigger on DCRC3pC threshold 13.
	DCRC3pB was railed through entire sequence