The Stratagem EH-4 transmitter consists of a dual loop antenna, transmitter electronics, and controller. The transmitter provides unpolarized source fields which allow for true tensor measurements of ground resistivities. This provides more accurate interpretation of true resistivities than conventional single-dipole transmitter source signals. The transmitter is powered by a 12 VDC battery.
The illustration above shows a typical configuration of the Stratagem receiver. The magnetic fields a detected with two perpendicular H-field sensors. The electric fields are detected by measuring the differential voltage between the two electrodes Ex0 and Ex1, for example.
Fast data collection and instrument set up
The operator can select the frequency bands and the number of time series "stacks" for data collection allowing optimization of high/low frequency data collection. Typical data collection time per station is 5 to 10 minutes. The Stratagem can then be moved and setup in from 5 to 10 minutes per station. This means complete setup and data collection can be done in 10 to 20 minutes giving from 3 to 6 stations per hour.