2019/04/22 (Monday)
| Status | Room temperature. All mixture in dump. LN2 traps, 4He trap, fridge all pumped out. 1K Pot needle valve closed. Cryostat vacuum jacket pumped out. Tower removed and reassembled, need to do Tower electrical checkout. |
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| 0920 | Start looking at SQUET ZC-13 for rebonding.  At least one broken wirebond in pA (lower left), looks like a SQUID connection. Will try to fix both the SQUID and the Feedback opens. |
| 1305 | Finish wirebonding ZC-13  pA (upper right): try to repair. Left Rshunt at 20 mΩ. pB (upper left): reduced shunt to 6.7 mΩ, shorted resistor to “sig coil” pC (lower left): reduced shunt to 6.7 mΩ pD (lower right): reduced shunt to 6.7 mΩ |
| 1345 | Perform electrical check on SQUET ZC-13 phonon channels - looks good. pA channel seems to be repaired. pB, pC, pD shunts reduced. pB sig-shunt shorted, shows 2 Ω at the bench between tower-side QET&QETbias (normally this is 20 kΩ from the input coil). |
| 1515 | Start looking at SQUET ZC-26 for rebonding. The pB SQUID chip is loose - that must be why it has so many problems. Borrowed som sort of epoxy (“Amber Clear Bonding Epoxy 220”) from Goldman lab and tried to epoxy it back down. |
| 1545 | Wirebond modifications on ZC-26: reduce pC and pD shunt resistances to 6.7 mΩ. Remove all wirebonds from pB, most had come loose. The chip was still loose, so I took it off completely, cleaned the surface a little then applied some GE Varnish (LakeShore VGE-7031) and put the chip back on and pushed it down. |
| 1605 | Rewirebond pB connections on ZC-26. Wired in the standard way, with 20 mΩ shunt. |
| 1620 | Perform electrical check on SQUET ZC-26 phonon channels. pA Feedback is still too low 1 kΩ. Otherwise OK. pB seems to be repaired now (hopefully varnish will set OK). |
| 1545 | Tower electrical check: |
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| Detector | G101c | DIB | 1 | ||
|---|---|---|---|---|---|
| side coax | ST-3-3 | date/who: | 2019-04-22 | NM & DS | |
| face | 5 | ||||
| +lead | - lead | signal | typical | previous | measured |
| 1 | 2 | QET A | 100 to 200 Ω | 207 Ω | 203 Ω |
| 2 | 4 | QETA-B | 100 to 200 Ω | 189 Ω | 209 Ω |
| 3 | 4 | QET B | 100 to 200 Ω | 158 Ω | 158 Ω |
| 4 | 6 | QETB-C | 100 to 200 Ω | 188 Ω | 179 Ω |
| 5 | 6 | QET C | 100 to 200 Ω | 197 Ω | 208 Ω |
| 6 | 8 | QETC-D | 100 to 200 Ω | 223 Ω | open |
| 7 | 8 | QET D | 100 to 200 Ω | 175 Ω | open |
| 2 | 8 | QETA-D | 100 to 200 Ω | 232 Ω | open |
| 9 | chassis | LED1 Rforward | 8 to 9 MΩ | 377 kΩ | 800 kΩ |
| 9 | chassis | LED1 Vforward | 1.0 to 1.1 V | 2.8 V * | 1.11 V |
| chassis | 9 | LED1 Rreverse | <1 nS | 15 mΩ | <1 nS |
| 10 | chassis | LED2 Rforward | 8 to 9 MΩ | 789 kΩ | 800 kΩ |
| 10 | chassis | LED2 Vforward | 1.0 to 1.1 V | 1.086 V | 1.10 V |
| chassis | 10 | LED2 Rreverse | <1 nS | <1 nS | <1 nS |
| All pins → Ground | <1.0nS | (Except for LED pins) | all <1 nS | all <1 nS | |
| Detector | G101c | DIB | 3 | ||
|---|---|---|---|---|---|
| side coax | ST-3-8 | date/who: | 2019-04-22 | NM & DS | |
| face | 3 | ||||
| +lead | - lead | signal | typical | previous | measured |
| 1 | 2 | QET A | 100 to 200 Ω | open | open |
| 2 | 4 | QETA-B | 100 to 200 Ω | open | open |
| 3 | 4 | QET B | 100 to 200 Ω | 131 Ω | open |
| 4 | 6 | QETB-C | 100 to 200 Ω | 155 Ω | open |
| 5 | 6 | QET C | 100 to 200 Ω | 138 Ω | 141 Ω |
| 6 | 8 | QETC-D | 100 to 200 Ω | open | open |
| 7 | 8 | QET D | 100 to 200 Ω | open | open |
| 2 | 8 | QETA-D | 100 to 200 Ω | open | open |
| 9 | chassis | LED1 Rforward | 8 to 9 MΩ | n/a | |
| 9 | chassis | LED1 Vforward | 1.0 to 1.1 V | n/a | |
| chassis | 9 | LED1 Rreverse | <1 nS | n/a | |
| 10 | chassis | LED2 Rforward | 8 to 9 MΩ | n/a | |
| 10 | chassis | LED2 Vforward | 1.0 to 1.1 V | n/a | |
| chassis | 10 | LED2 Rreverse | <1 nS | n/a | |
| All pins → Ground | <1.0nS | (Except for LED pins) | all <1 nS | all <1 nS | |
| Detector | G101c | DIB | 4 | ||
|---|---|---|---|---|---|
| side coax | ST-3-10 | date/who: | 2019-04-22 | NM & DS | |
| face | 1 | ||||
| +lead | - lead | signal | typical | previous | measured |
| 1 | 2 | QET A | 100 to 200 Ω | open | open |
| 2 | 4 | QETA-B | 100 to 200 Ω | open | open |
| 3 | 4 | QET B | 100 to 200 Ω | 162 Ω | open |
| 4 | 6 | QETB-C | 100 to 200 Ω | 189 Ω | open |
| 5 | 6 | QET C | 100 to 200 Ω | 200 Ω | 200 Ω |
| 6 | 8 | QETC-D | 100 to 200 Ω | 232 Ω | 233 Ω |
| 7 | 8 | QET D | 100 to 200 Ω | 223 Ω | 224 Ω |
| 2 | 8 | QETA-D | 100 to 200 Ω | open | open |
| 9 | chassis | LED1 Rforward | 8 to 9 MΩ | 792 kΩ | 800 kΩ |
| 9 | chassis | LED1 Vforward | 1.0 to 1.1 V | 1.087 V | 1.1 V |
| chassis | 9 | LED1 Rreverse | <1 nS | <1 nS | <1 nS |
| 10 | chassis | LED2 Rforward | 8 to 9 MΩ | 785 kΩ | n/a |
| 10 | chassis | LED2 Vforward | 1.0 to 1.1 V | 1.082 V | n/a |
| chassis | 10 | LED2 Rreverse | <1 nS | <1 nS | n/a |
| All pins → Ground | <1.0nS | (Except for LED pins) | all <1 nS | all <1 nS | |
| Detector | G101c | DIB | - | ||
|---|---|---|---|---|---|
| side coax | - | date/who: | 2019-04-22 | NM & DS | |
| face | 2 | ||||
| +lead | - lead | signal | typical | previous | measured |
| 1 | 2 | QET A | 100 to 200 Ω | open | 58 Ω * |
| All pins → Ground | <1.0nS | (Except for LED pins) | all <1 nS | all <1 nS | |
* This is the two pins that are connected to the electrode.
| 1654 | Install tower in fridge, tape down thermometer wire. |
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