| | 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 → DCRC55(1)/DCRC50(3) |
| 0610 | Tower = 42.8 mK |
| | overnight: at 4:10 the 1K Pot press/temp started to fall. By 6:05 it had fallen below 2 mbar and stopped oscillating. At the same time the Condenser pressure fell from 100→90 mbar and the Tower temperature rose from 42.7→43.1 mK. Not a complete failure like yesterday but the pot is very low and probably would have failed if it went for a few more hours. |
| 0840 | Tower/MC/Coldplate = 43.2/39.2/218 mK, Still = 1.28 K / 0.045 mbar, G1/G2 = 91/82 mbar, 1K Pot = 1.37 K / 1.6 mbar. MB = 75.1% |
| 0840 | Open 1K Pot needle valve +10 degrees |
| 0850 | Tower/MC/Coldplate = 41.7/38.0/213 mK, Still = 1.33 K / 0.050 mbar, G1/G2 = 116/105 mbar, 1K Pot = 1.58 K / 14 mbar. |
| 0855 | Fill LN2 cold trap bath |
| 0940 | 1K pot = 1.42 K / 3.4 mbar. Open 1K Pot needle valve +10 degrees |
| 1144 | 1K pot = 1.45 K / 2.4 mbar. Open 1K Pot needle valve +15 degrees |
| 1448 | 1K pot = 1.40 K / 2.0 mbar. This isn't working. Let's just stop circulation over the weekend. Close V6 to stop circulation. |
| 1455 | Base temp is rising to ~140 mK, close needle valve. Pr flattens out at 0.55 mbar |
| 1458 | Close 4He pump valve. P2 rises slowly to 5 mbar. |
| 1500 | Open 1K pot needle valve slowly. At ~40 degrees, P2 starts to increase faster and goes off scale. 1K pot temperature slowly rises to 1.9 K |
| 1504 | Open 1K pot needle valve another ~40 degrees, 1K pot temp rises a bit faster. Close needle valve with 1K pot temperature = 2.0 K |
| 1505 | Turn off 3He pump as it's rather loud. Use 4He pump to pump out up to V4A. Open V4A until P2 = 1000 mbar, then close V4A and let 4He pump pump out that. Repeat a few times. |
| 1510 | 1K pot = 1.3 K. |
| 1520 | P2 < 1 mbar, G1=40 mbar. Open 1K pot needle valve 30 degrees. P2 climbs to 1.5 mbar before starting to fall again. This is like starting the 1K pot but with a smaller load since the condenser is less full. |
| 1522 | Open 1K pot needle valve +20 degrees. P2 rises to 3 mbar and remains flat. |
| 1525 | Open 1K pot needle valve +30 degrees. P2 rises to 6.5 mbar and remains flat for a minute, then rises quickly and starts slow (1 min period) oscillation around 25 mbar. 1 K pot temp follows suit, oscillating around 1.6 K |
| 1538 | Open V9 and V3 |
| 1541 | Fill LN2 cold trap full. |