| | Status: Cooled to base yesterday. |
| | overnight: Tower and pressures somewhat unstable, but remained between 29 mK and 31 mK. 1K pot fell to 3 mbar, but then slowly rose to 4 mbar. |
| 1417 | Tower = 29.7 K, G1/G2 = 172/160 mbar, 1K Pot = 1.45 K / 4.0 mbar. |
| 1420 | Fill LN2 cold trap full. |
| 1421 | Power on DCRCs 1,3. Start DCRC programs. Tower spikes to 175 mK, but starts cooling again quickly |
| 1425 | Tower = 35 mK and falling |
| 1428 | Open 1K Pot needle valve → 140°. 1K Pot → 1.58 K / 14 mbar |
| 1430 | DCRC programs keep crashing. Soft RESET DCRCs 1,3. Unable to telnet to DCRC4. Power cycle DCRC4. That seemed to work. |
| | noticed that the bias voltage spiked to 12V and back |
| 1435 | All channels working and the strange noise seems to be gone! |
| 1440 | Start 60-minute 0 V background data series, Driver Gains = 2x, QET biases = (280/260/305)/(140/295/300) uA, Front-End Gains = 10, 1000 initial randoms, trigger on DCRC3pB/C/D threshold = 8/16/16. To be compared to noisy data taken 2018/07/17 |
| 1441 | Tower = 29.8 mK, 1K pot = 1.6 K / 9.0 mbar |
| 1855 | Set HV=40 V using changeHV_0_40_preBias15_5.msl |
| 1858 | Tower = 30.8 mK, 1K pot = 1.47 K / 4.5 mbar |
| 1904 | Start 60-minute 40 V background data series, Driver Gains = 2x, QET biases = (280/260/305)/(140/295/300) uA, Front-End Gains = 10, 1000 initial randoms, trigger on DCRC3pB/C/D threshold = 8/16/16. |
| 1609 | Leakage voltage is >50 mV, turn on LN2 gas line to e-box. Open the valve wide for a few seconds to purge the bag, then reduce it so there is just a slow flow of gas. Leakage voltage begins falling. |