2021/03/14 (Sunday)
- Lab in-person: Ruiren
- Virtual partner: Matt
| Status | Run 74 in progress. |
|---|---|
| Setup: DIB1/2+acc → SL 41/43 → 3.2 MHz filters → cables 2/3 → nothing/HV_diverter_board → DCRC50(3)/55(1). Kepco 0-40V supply → HV BNC. No lead/poly shield. | |
| 1152 | MB = 67.2% |
| 1115 | Tower = 93.6 mK |
| 1245 | Noise in DCRC3qI/qO/DCRC1qI/qO = 1.9/1.3/4.4/1.6 e-6 @ 10 kHz |
| Let's try some data now, with the Kepco 0-40V supply plugged into the HV diverter board at 0V. We'll bias Side1 with DCRCs. | |
| 1257 | Start 31min series of +11V/0V data (bias applied after 1 min), with 1000 beginning randoms, trigger threshold 40/40/40/40 on DCRC3qI/qO/DCRC1qI/qO, no in-run randoms, with 1.6384 ms pulses (8192 length) and 400 us prepulse (500 length). Use sequence r74_takeandflash_dcrcbias.msl |
| Triggering looks OK | |
| 1530 | Ruiren enters lab |
| 1530 | Tower/MC/Coldplate = 92.3/37.9/187 mK, Still = 1.46 K / 0.130 mbar / 0 mW, G1/G2 = 364/320 mbar, 1K Pot = 1.69 K / 40±2 mbar. |
| 1538 | Start 31min series of 0V/-15V data (bias applied after 1 min), with 1000 beginning randoms, trigger threshold 40/40/40/40 on DCRC3qI/qO/DCRC1qI/qO, no in-run randoms, with 1.6384 ms pulses (8192 length) and 400 us prepulse (500 length). Start sequence with Start button. |
| 1548 | Unfortunately noise is pretty terrible now. DCRC3qO is particularly screwy, that's q1. Increase trigger thresholds → 120/off/120/100 |
| Noticed later that Tower temperature increased after applying bias, from 92→138 mK, then fell again when the bias was reduced to 0V. | |
| 1607 | Dial HV back to 0V. Noise gets much better. Stop data series. |
| 1615 | Flash LEDs on DCRC1&3 for 30 seconds |