2021/06/16 (Wednesday)

Status	Run 74 in progress. First cooldown after IVC rebuild. Started circulation last week.
	Tower thermometer is reading high, probably this is a thermometer problem and the actual temperature is much lower. High noise in some of the charge channels.
	Setup: DIB1/2+acc → SL 41/43 → 3.2 MHz filters → cables 2/3 → nothing/Source_mover_board+HV_diverter_board → DCRC50(3)/55(1). Kepco 40V supplye → HV BNC. No lead/poly shield.
1245	Tower/MC/Coldplate = 206/32.3/198 mK, Still = 1.43 K / 0.085 mbar / 0 mW, G1/G2= 161/149 mbar, 1K Pot = 1.65 K / 28±2 mbar. MB = 60.1%
1250	Fill LN2 cold trap bath
1255	At 10kHz noise in DCRC3qI/qO/DCRC1qI/qO = 73/10/34/104 e-6. This is q3/q1/q4/q2
	let's also look at the noise peak at around 3 kHz.
1300	At 3kHz (peak) noise in DCRC3qI/qO/DCRC1qI/qO = 4100/600/400/4800 e-6. This is q3/q1/q4/q2
	so the worst one is q2, with q3 coming in second. But it's a split decision with the other two channels: q1 is less noisy at 10kHz but q4 shows less of the 3 kHz peak (q4 was in general not showing much of that oscillation yesterday).
1340	Set up N2 purge of e-box. Run a rubber hose from the LN2 Dewar exhaust into a plastic bag taped around the end of the e-box and around the cables. Open the LN2 vent valve just a little, so that I can barely hear gas flowing with my thumb mostly covering the port.
1705	At 10kHz noise in DCRC3qI/qO/DCRC1qI/qO = 55/7.6/21/80 e-6. This is q3/q1/q4/q2 At 3kHz (peak) noise in DCRC3qI/qO/DCRC1qI/qO = 2500/390/260/4100 e-6