Tuesday, December 15, 2020, 11:15

Vacuum at 1.0e-6 Torr. Turned bias power supply on, starting HV ramp at 500 V increments, increasing every 30-50 seconds seconds or so.

Tuesday, December 15, 2020, 12:47

Reached 50 kV. Not a single dip in voltage, significant current bump, or change in vacuum up to this point. Will hold for 10 minutes before continuing.

Tuesday, December 15, 2020, 12:57

Continuing voltage ramp. Decreasing increments to 250 V as this is uncharted territory, and that rate of increase seemed safe yesterday. Will also hold at each voltage for about 2 minutes after no signs of activity.

Tuesday, December 15, 2020, 13:04

Small dip in voltage and wiggle in current at 50.75 kV, no change in vacuum.

Spark at 51.25 kV with change in vacuum; reduced voltage temporarily. Did the same at 51.75 kV. Did the same at 52 kV, but let it sort itself out this time since it didn't seem too violent.

Actual spark at 52.25 kV with big voltage drop, and I saw it happen. On the vacuum gap side, somewhere in the flat plane and close to the middle. Another spark after about 3 minutes of holding. Just missed recording it but I saw it on the feed of the GoPro; maybe in a similar location as the previous. Another 1 minute later, didn't see it this time. The last two had no effect on vacuum.

Tuesday, December 15, 2020, 13:31

5 minutes since last spark. Raising voltage again, this time recording with GoPro. Spark captured at 53 kV. No change in vacuum... until a minute later.

Tuesday, December 15, 2020, 14:46

55 kV. Each time voltage is raised, it takes a couple seconds to reach a stable voltage. During this time the current limit of 0.005 mA seems to be drawn. Will reduce current limit to 0.001 mA to see effect. Dumped StripTool data at 55.25 kV.

Recorded spark at 56 kV. Voltage took longer to recover as a result of the reduced current limit.

58.5 kV. Effect of reducing current limit seems to make it take longer to reach a stable voltage. I think this is a good thing as it should smooth out the conditioning. Sparked here twice, reduced voltage for a bit before bringing back up again.

Tuesday, December 15, 2020, 16:23

60 kV. Sparked twice. Carla observed some: a couple small ones on the face of the insulator as the voltage was recovering from the first spark followed by a large one that went all the way across. Only the larger events seem to be captured by the GoPro.

Tuesday, December 15, 2020, 16:47

Finished holding at 60 kV to 20 minutes with no sparks other than the other two previously mentioned. Resuming voltage increases.

Tuesday, December 15, 2020, 17:02

61.5 kV. Small spark but not full breakdown, then a large spark that cut voltage to 0 V. Voltage dropped relatively slowly to about 48 kV. Lowered the voltage limit to 44 kV. During this entire time, 0.001 mA of current was being drawn. Carla started raising voltage while increasing the current limit as needed to reach the set voltage.

Tuesday, December 15, 2020, 17:44

Back at 60 kV and holding. Drawing 0.005 mA to 0.006 mA though. This is different from earlier when it was holding 60 kV with no current draw.

Tuesday, December 15, 2020, 19:02

Held 60 kV for an hour with current staying constant around 0.005 mA. Ramped down (first ramped down current to see effect) and then ramped down voltage. Shut off power supply.