TDEM-20BT

This unit is a microcomputer controlled data acquisition system.

It is intended for time domain EM surveys An Android 7" tablet is used user interface and data logger. The TDEM-20BT application will only function with this hardware.

Graphic area

This is the main area on the screen where the decay curve is shown graphically. Gate start and end position shown with blue ticks.

Current GPS coordinates

The bottom left (green) panel is used to display the current GPS data, if available.

General Info

This panel (gray) is used to display prompts, warnings and general info.

START

After all the parameters have been set up, use this button to start a reading.

READ

Use this button to retrieve data from the data logger. Data will be shown in Graphic screen.

LOAD

Load a file from internal storage to display.

SAVE

After the data logger has completed the stacking process, use this button to save the data to internal storage

Export

Data can be exported in CSV format for use in a spreadsheet or to Amira format to be used in modeling of the data.

File Name

Use the area to the right of File Name to enter new file names.

TX coil size

Use the spinner option to select the coil size used.

TX coil turns

Use the spinner option to select the number of turn in the transmitter coil.

TX pulse

Use the spinner option to select the transmitter pulse width to be used.

Coil Spacing

Use the spinner option to select the coil spacing that will be used (centre to centre of TX and RX coil

Stacks

Use the spinner to select the number of times the transmitter will be pulsing the TX coil

Delay

Use the spinner option to select the delay to be used before sampling of the received signal starts.

RX sample rate

The received signal is digitized at a fixed rate for 800 samples. This option sets the time between samples

RX gain

Use the spinner option to select the preamplifier gain to be used.

BT Connect

Before starting to take readings communications between the Tablet and the Data logger must be set up.

GPS

The coordinates of the station will be incorporated in the data file if GPS use is enabled with this function.

SS

When field data is being displayed a screen shot can be made by pressing this button.

RXbat%=

For each station the battery voltage of the receiver and the transmitter will be retrieved from the data logger, the Receiver battery status is displayed here as a % of full capacity.

TXbat%=

For each station the battery voltage of the receiver and the transmitter will be retrieved from the data logger, the Transmitter battery status is displayed here as a % of full capacity.

Scale Mod

When the signal is small, in late time, it can be enlarged with this spinner option to get a better idea of noise levels.