| Status | Run 76 beginning. Started circulation yesterday |
| 1115 | Goldman/MC/Coldplate = 80.6/27.8/140 mK, Still = 1.11 K / 0.140 mbar / 0 mW, G1/G2= 78/88 mbar, 1K Pot = 20° / 1.74 K / 190±30 mbar. MB = 26.3% |
| | The Goldman thermometer is almost certainly reading incorrectly, unfortunately. It's connected to the fridge thermometer wires in this run - in the previous run we used the stripline wires. The Tower thermometer was connected to the fridge wires in the last several runs and read anomalously high and unstably. I suspected the thermometer in part because testing for shorts between the fridge wires at room temperature revealed no problems. Now I suspect the wires. |
| 1125 | Tweak the 1K Pot needle valve closed a bit more, → 18°. 1K Pot → 1.72 K / 100±20 mbar |
| 1155 | Switch the 10 dip switches on the diverter board corresponding to accessory wires to OFF. Using the map on the run summary. |
| 1215 | Start MIDAS. Set up DCRCs for 2-sided 0-volt readout. Cable 2/1/3 → diverter/nothing/nothing → DCRC 1/3/4 |
| 1225 | Start DAQ programs. Check traces with pulse viewer. Some railed, some noise, some show good pulses. |
| 1230 | MC temperature rose when DCRCs were connected, then relaxed, now 31.3 mK and cooling. |
| 1230 | Zap SQUIDs on all 3 DCRCs. |
| 1340 | MC = 29.2 mK, 1.4 mK higher than before DCRCs were powered. |
| | Consulting Feb 1 run diary to get SQUID and QET settings from Run 75. SQUETs are rearranged in this run. We'll set the same SQUID settings according to the SQUET and the QET biases according to the detector channels. |
| 1445 | Messing with the phonon channels. Seeing good pulses on DCRC3 pA,B and DCRC4 pA,B,C,D, not the other six. None of the DCRC1 channels show pulses, strange. |
| 1450 | Turn off DAQ programs and power down DCRC1, then remove diverter board and plug in Cable 2 directly … actually this is probably a bad idea… |
| 1540 | Check diverter board with a meter, looks good - the accessory pins show open from input to output, all others are continuous. (At least according to the table on the run summary.) |
| 1545 | Reconnect Cable 2 to DCRC1 as before, with diverter board, power up DCRC1. Another spike in temperature, Goldman → 65 mK then cools. |
| 1557 | Begin LHe transfer @ MB = 17.4% |
| 1639 | End LHe transfer @ MB = 74.4% |
| 1655 | Fill LN2 cold trap bath |