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0900 Remove MC spool. Took spool to machine shop, where they retapped all six holes in the bottom.
In discussing this situation the issue of screw material for thermal contacts arose again. Vuk and Matt questioned the use of steel screws, which are poor thermal conductors and which contract less than copper or brass when cooled, which will make the connections between copper surfaces weaker. It would be better to use brass screws for key thermal connections: at the 30 mK level, these are MC-spool, spool-can, can-adapter, adapter-tower. But socket-head brass screws in metric sizes must be special ordered, and for MC-spool and can-adapter the angle requires socket-head. So for this run we'll use brass for the spool-can and adapter-tower connections (these can be Philips-head) and get a quote for socket-head ones to use for the MC-spool and can-adapter connections. Note that 12 lb*in is too much torque for the copper screws - we need to look up what would be appropriate for brass M3 screws.
1500 Reattach MC spool
1515 Finish assembling tower. Taped thermometer wire down and ran it through hole in adapter plate.
note on exposure: the tower (with G110) was - I think - left on the bench in the cleanroom overnight. It will be left that way tonight as well. The stated reason not to put it in purge is that the Pb-210 source is considered somewhat dirty…. (should get clarification from Hassan)…
another note: the thermometer was mounted on the plate on the top of the source holder (which is on top of the stack) with the screw sticking out the top, preventing a lid from fitting on top of the stack. We left it that way this evening but this should be redone: the screw should be put through in the opposite direction, and a housing lid should be put on top.
another note: the standard steel M3x12 screws were used to attach the adaptor plate to the tower, but we should use brass screws instead, which should arrive tomorrow from McMaster.
also we will use the newly arrived M3x12 brass screws to attach the 30 mK can to the MC spool.
Table 2 - Tower checkout
Detector G110 DIB 1
side coax ZB1-6 date/who: 2015-04-23 MF & AK
face 2
+lead - lead signal typical measured
1 2 QET A 100 to 200 Ω 211 Ω
2 4 QETA-B 100 to 200 Ω 229 Ω
3 4 QET B 100 to 200 Ω 214 Ω
4 6 QETB-C 100 to 200 Ω 217 Ω
5 6 QET C 100 to 200 Ω 170 Ω
6 8 QETC-D 100 to 200 Ω 205 Ω
7 8 QET D 100 to 200 Ω 163 Ω
2 8 QETA-D 100 to 200 Ω 213 Ω
10 chassis LED2 Rforward 8 to 9 MΩ 720 kΩ
10 chassis LED2 Vforward 1.0 to 1.1 V 1.059 V
chassis 10 LED2 Rreverse <1 nS <5 nS
9 chassis LED1 Rforward 8 to 9 MΩ 16 kΩ
9 chassis LED1 Vforward 1.0 to 1.1 V 1.039 V
chassis 9 LED1 Rreverse <1 nS closed
1 11 Qo Rbias 24 to 26 nS 26 nS
12 11 Qo C coupling <1 nS <0.1 nS
12 13 Qo Rfeedback 24 to 26 nS 26 nS
1 14 Qi Rbias 24 to 26 nS 26 nS
15 14 Qi C coupling <1 nS <0.2 nS
15 16 Qi Rfeedback 24 to 26 nS 26 nS
Detector G110 DIB 2
side coax ZB1-1-9 date/who: 2015-04-23 MF & AK
face 5
+lead - lead signal typical measured
1 2 QET A 100 to 200 Ω 182 Ω
2 4 QETA-B 100 to 200 Ω 169 Ω
3 4 QET B 100 to 200 Ω 113 Ω
4 6 QETB-C 100 to 200 Ω 167 Ω
5 6 QET C 100 to 200 Ω 164 Ω
6 8 QETC-D 100 to 200 Ω 160 Ω
7 8 QET D 100 to 200 Ω 115 Ω
2 8 QETA-D 100 to 200 Ω 178 Ω
9 chassis LED1 Rforward 8 to 9 MΩ 699 kΩ
10 chassis LED2 Rforward 8 to 9 MΩ 702 kΩ
9 chassis LED1 Vforward 1.0 to 1.1 V 1.055 V
10 chassis LED2 Vforward 1.0 to 1.1 V 1.56 V
chassis 9 LED1 Rreverse <1 nS <5 nS
chassis 10 LED2 Rreverse <1 nS closed
1 11 Qo Rbias 24 to 26 nS 25 nS
12 11 Qo C coupling <1 nS <0.1 nS
12 13 Qo Rfeedback 24 to 26 nS 26 nS
1 14 Qi Rbias 24 to 26 nS 26 nS
15 14 Qi C coupling <1 nS <0.1 nS
15 16 Qi Rfeedback 24 to 26 nS 26 nS
Detector G110 DIB 3
side coax ZB1-1-11 date/who: 2015-04-23 MF & AK
face 6
+lead - lead signal typical measured
1 2 QET A 100 to 200 Ω 161 Ω
2 4 QETA-B 100 to 200 Ω 202 Ω
3 4 QET B 100 to 200 Ω 286 Ω
4 6 QETB-C 100 to 200 Ω 196 Ω
5 6 QET C 100 to 200 Ω 178 Ω
6 8 QETC-D 100 to 200 Ω 190 Ω
7 8 QET D 100 to 200 Ω 131 Ω
2 8 QETA-D 100 to 200 Ω 179 Ω
9 chassis LED1 Rforward 8 to 9 MΩ open
9 chassis LED1 Vforward 1.0 to 1.1 V OL
chassis 9 LED1 Rreverse <1 nS <0.2 nS
10 chassis LED2 Rforward 8 to 9 MΩ open
10 chassis LED2 Vforward 1.0 to 1.1 V OL
chassis 10 LED2 Rreverse <1 nS <0.3 nS