The following are details of my first set of ion measurements in my Hamel 45 Gallon Drum Mark 2. They are preliminary as not much time was spent doing the measurements.

Probe lowered into the hole

I tried the probe in various locations inside top area of the drum. Best results were when the probe tip was touching the skin of the inner cone of the top cone. This is what is being shown in the above picture. The tip was kept in constant contact and not interfering with the cone wobble by my holding the ion meter very lightly. Nothing was registered on the meter when the tip was held close to but not touching the cone skin.

As a sanity check, I also removed the meter altogether from the drum and held it upside down as if it were in the drum and wiggled it as if it were being moved by a wobbling cone. This was done to see if the meter reading was due to the movement of the meter. The meter did not register anything in this case so the readings when in the cone were not due to the movement of the meter.