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2018/03/12 (Monday)

	Status: warming. Main bath empty. LN2 traps pumped out, mixture in dump. 1K Pot evacuated and isolated. Helium and nitrogen in cryostat vacuum jacket.
0905	MC(Cernox) = 258.7 K Warming time constant now only 15 hours, suggests fridge will hit 273 K late this afternoon, 16:20.
1100	MC(Cernox) = 263.3 K. Should hit 273 K at about 16:07
1510	Check the other two side coaxes that we can use this run (these are sCDMS short, with names like ST-4-something)

+lead	- lead	signal	typical	measured
Side coax	ST-3-8
	date:	2018-03-02	who:	MF
D11	T11	Qo Rbias	25 nS	25 nS
T12	T13	Qo Rfeedback	25 nS	25 nS
D11	T12	Qo C coupling	<1 nS	0.06 nS
D12	T14	Qi Rbias	25 nS	25 nS
T15	T16	Qi Rfeedback	25 nS	25 nS
D12	T15	Qi C coupling	<1 nS	0.05 nS
all	chassis	isolation	<1 nS	OK

The one above is the extra one, looks like it's in good working order

+lead	- lead	signal	typical	measured
Side coax	ST-3-9
	date:	2018-03-02	who:	MF
D11	T11	Qo Rbias	25 nS	0.05 nS
T12	T13	Qo Rfeedback	25 nS	0.08 nS
D11	T12	Qo C coupling	<1 nS	12 kΩ
D12	T14	Qi Rbias	25 nS	0.07 nS
T15	T16	Qi Rfeedback	25 nS	25 nS
D12	T15	Qi C coupling	<1 nS	0.06 nS
all	chassis	isolation	<1 nS	OK

The one above is the one I tried to fix and failed. It sure is a mess. Not only 3 open resistors, but a shorted or blown capacitor.

1615	Check IVC pressure: 120 mbar. Note that the overpressure valve was opened yesterday, worried that it might have trapped helium.
1620	Start letting N2 into IVC, interestingly the pressure on the Pfeiffer gauge initially went down, not up. Helium must read higher pressure than nitrogen on that gauge.
1635	Fill IVC with about 1 bar of N2
1635	MC(Cernox) = 274.1 K by the LabVIEW vi. 272.8 K by the LakeShore bridge display.
1645	Measure pressure in cryostat vacuum jacket: 12 mbar, like yesterday.
1645	Begin pumping out cryostat vacuum jacket with scroll pump
1700	Switch to pumping out cryostat vacuum jacket with turbo pump