Where is the Pulse measurement being taken from?

The Pulse Meter measurement is taken at the active tips (2 inches / 50mm from the tip of the probe to the plastic divider). One of the tips emits the measurement frequencies while the other detects and measures these.

The total volume the Pulse measures will depend on the media it is in, for example it will measure a larger volume of water than it would of soil as water transmits radio frequencies better than soil. As a guide in soil the Pulse will typically measure a volume size similar to a standard drink can, with the active tips in the middle.