2022/02/08 (Tuesday)
- Lab in-personnel: Matt, Giulia, Himangshu, Shubham
| Status | Run 75 in progress |
|---|---|
| Setup | Tower Faces 5/3/2 → Cables 2/1/3 → nothing/diverter_board+extra_board/nothing → HVboard CONN1/2/3 → HV1/2 → DCRC55(1)/50(3) Lead shield in place. Am Source y = 30.03 mm |
| 1330 | Goldman/Tower/MC(H35)/Coldplate = 41.0/68.7/32.5/181 mK, Still = 1.38 K / 0.110 mbar / 0 mW, G1/G2= 257/247 mbar, 1K Pot = 1.58 K / 11±1 mbar, MB = 64.9% |
| 1510 | Goldman/Tower/MC(H35) = 38.2/66.9/30.1 mK ← these were measured after we disconnected the DCRCs, when temperatures were cooler. |
| 1320 | Fill LN2 cold trap bath. |
| 1430 | Solder jumper wires on Side2-readout HV board so that LEDs will be connected: CONN2 Pins 26/42 → CONN4 Pins 26/42 |
| 1500 | Turn off DAQ programs, power down DCRC1&3, disconnect HV board, swap out Side1-readout HV board from case and replace with Side2-readout HV board, reattach cables and DCRC1&3 to Side2-readout HV board. |
| 1510 | Adjust SQUID and QET settings on DCRC1&3 channels to match the Side2-readout board map. Using the original 2-sided 0V settings from Jan 31. |
| 1525 | Power up DCRCs. Temperature spikes to 0.2 K but then cools again. Try looking at channels - a lot of railed channels. Zap SQUIDs and let cool again. |
| 1535 | Some channels can't be unrailed. Others can be relocked/unrailed, but they look a bit like open channels - noise lower then normal and not responsive to QET bias changes. One channel appears to be working, shows pulses and noise is OK: DCRC3pB (Side2pA). |
| 1600 | Messing around with connections and adjusting QET biases, looks like most/all channels now have pulses. But there are high-frequency noise peaks, ~ 60 kHz. |
| 1615 | HV control seems to have shifted, minimum output now corresponds to DCRC2qI = 11.67 rather than 11.64. |
| 1615 | Set HV back to positive polarity on Kepco 1kV supply. Reconnect HV cable to HV board. |
| 1620 | Seeing pulses in all channels |