2016/03/25 (Friday)
| Checking G114 to determine what may be causing the DIB1 pA disconnect. Unmount detector from tower (place rest of tower back in purge cabinet), and examine wirebonds on Side 1 of detector. No obvious broken bonds on DIB1. | |
| Measure resistances between Pin1 and all other DIB1 pins. All open. | |
| Measure resistances between Pin2 (other pA pin) and all other DIB1 pins. Pin2 shows connections to several other pins (not LEDs). So the culprit is indeed Pin1. | |
| Attempt to carefully measure resistance between Pin1 on DIB1 and the corresponding internal Pad1 of DIB1. After some careful maneuvering, I was finally able to get a reading to register on the meter, though it was higher than expected: ~220Ω). |
| 1600 | Performing resistance measurements to determine source of current leakage when attempting iZip HV mode with HV box. Previously found 600-700 MΩ total resistance which, accounting for the bias resistor, was evidence of 200-300 MΩ through which the current was leaking. |
|---|---|
| Using Megger for all measurements. Checked calibration by measuring 400MΩ bias resistor on HV box and found it to be spot on. | |
| All measurements taken across HV box BNC connector. |
| Setup | elapsed time | Resistance | Leakage current (nA) (500V source) |
|---|---|---|---|
| HV board | 0 | > 2 TΩ | < 0.25 |
| HV board + cables (disconected from ebox) | 0 | 1 GΩ | 500 |
| 1 min | 100 GΩ | 5 | |
| 3 min | > 2 TΩ | < 0.25 | |
| HV board + cables + striplines (room temp, tower removed) | 0 | 1GΩ | 500 |
| 1 min | 10 GΩ | 50 | |
| 2 min | 20 GΩ | 25 | |
| 3 min | 30 GΩ | 17 | |
| 4 min | 35 GΩ | 14 | |
| 5 min | 40 GΩ | 13 | |
| 10+ min | 70 GΩ | 7 |
| The last test was repeated with 2 DCRCs with filters attached to HV box with identical results. |