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2012/06/29

0020 Conduct tower level continuity check. Found short to ground. Take side coaxes off one-by-one and try to isolate short.
0230 Found source of short: pins 7 & 8 on new SCUHBA extender plug PCB are shorted. Tried to look for visible signs of short, but could not find any. Additionally, ran soldering iron across mask in attempt to remove solder: did not work… well partly worked as resistance is now 15 MΩ rather than 0.2 Ω. Finally, tried to scrap solder off with scalpel: no luck. Will discuss with others present for possible solution.
0425 Had a brief discussion. Looked under microscope, but nothing seemed untoward. Conducted another electrical check, and found that board is acting as a capacitor. All pins seem to be shorted, but resistance keeps rising. Did not notice this increase before. Looks like running the soldering iron over the mask did the trick.
Adapter plate requires some work. We do not have the necessary tools to do this easily. Will have to wait for mechanical workshop to open in the morning. Therefore, stop all work. Go home, get some sleep. It's going to be a busy day. Leave tower in clean room. Finish assembly and electrical checks in the morning.
Fill N2 cold trap full.
1130 Stop pumping on dewar.
1240 Fill N2 cold trap full.
1300 Pump mixture into dump in preparation for cleaning cold traps.
1330 Start cleaning nitrogen and helium cold traps.
Resume tower assembly procedure.
1440 Conduct tower level continuity checks:
Detector G103a DIB 1
side coax ZB1-1-6 date/who: 2012-06-29 HC & 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 235 Ω
3 4 QET B 100 to 200 Ω 219 Ω
4 6 QETB-C 100 to 200 Ω 216 Ω
5 6 QET C 100 to 200 Ω 188 Ω
6 8 QETC-D 100 to 200 Ω 204 Ω
7 8 QET D 100 to 200 Ω 152 Ω
2 8 QETA-D 100 to 200 Ω 210 Ω
chassis 10 LED2 Rforward 8 to 9 MΩ 755 kΩ
chassis 10 LED2 Vforward 1.0 to 1.1 V 1.088 V
10 chassis LED2 Rreverse <1 nS <0.8 nS
1 11 Qo Rbias 24 to 26 nS 26 nS
12 11 Qo C coupling <1 nS <0.4 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 <0.4 nS
15 16 Qi Rfeedback 24 to 26 nS 26 nS
Detector G103a DIB 2
side coax ZB1-1-9 date/who: 2012-06-29 HC & AK
face 5
+lead - lead signal typical measured
1 2 QET A 100 to 200 Ω 201 Ω
2 4 QETA-B 100 to 200 Ω 182 Ω
3 4 QET B 100 to 200 Ω 116 Ω
4 6 QETB-C 100 to 200 Ω 183 Ω
5 6 QET C 100 to 200 Ω 166 Ω
6 8 QETC-D 100 to 200 Ω 169 Ω
7 8 QET D 100 to 200 Ω 117 Ω
2 8 QETA-D 100 to 200 Ω 192 Ω
chassis 9 LED1 Rforward 8 to 9 MΩ 754 kΩ
chassis 10 LED2 Rforward 8 to 9 MΩ 774 kΩ
chassis 9 LED1 Vforward 1.0 to 1.1 V 1.086 V
chassis 10 LED2 Vforward 1.0 to 1.1 V 1.088 V
9 chassis LED1 Rreverse <1 nS <2.0 nS
10 chassis LED2 Rreverse <1 nS <0.9 nS
1 11 Qo Rbias 24 to 26 nS 25 nS
12 11 Qo C coupling <1 nS <0.3 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 <0.3 nS
15 16 Qi Rfeedback 24 to 26 nS 26 nS
Detector G103a DIB 3
side coax ZB1-1-11 date/who: 2012-06-29 HC & AK
face 6
+lead - lead signal typical measured
1 2 QET A 100 to 200 Ω 186 Ω
2 4 QETA-B 100 to 200 Ω 230 Ω
3 4 QET B 100 to 200 Ω 210 Ω
4 6 QETB-C 100 to 200 Ω 189 Ω
5 6 QET C 100 to 200 Ω 132 Ω
6 8 QETC-D 100 to 200 Ω 213 Ω
7 8 QET D 100 to 200 Ω 208 Ω
2 8 QETA-D 100 to 200 Ω 232 Ω
chassis 9 LED1 Rforward 8 to 9 MΩ 765 kΩ
chassis 9 LED1 Vforward 1.0 to 1.1 V 1.086 V
9 chassis LED1 Rreverse <1 nS <0.9 nS
1455 Tower assembly procedure completed. Tower taken to mini-clean room to commence installation.
Figure 1: Assembled tower.
Figure 2: New adapter plate with space for tower themometer wire.
Figure 3: Tower attached to 30 mK stage.
1725 Place nitrogen traps back in bath. Start cryocleaning mixture through nitrogen cold trap 2.
1805 Fill N2 cold trap full.
1945 Found a short during electrical check. Start investigating. Look at SQUET card & stripline pairs one-by-one.