Sonde Transmitter: Why, When, and How to Use it


It is costly when your HDD equipment cuts through utilities or other cables. Reports show the cost of damaged utilities is nearly $1.5 billion. That doesn’t include the damage to drilling equipment or associated downtime.

When drilling horizontally, how do you know where the drill head is?

You use a sonde transmitter. Inserted into the drill head, the sonde tells the drill operator the location of the drill head. It sends back information on depth, roll, operating temperature, and battery status. Now the operator can avoid utilities and exit the ground at the right spot.

Read on to learn how to use a sonde transmitter and keep your drilling practices accurate and safe.

Calibrate The Sonde Transmitter

Before each operation, calibrate the sonde to ensure accurate depth readings. Roll, pitch, battery level, and temperature do not need to be calibrated.

Calibration may differ depending on the models of subsite transmitters you have. For the Subsite 750 Tracker, place the sonde in the drill head and the receiver at exactly 10 feet away. Make sure the receiver is parallel to the sonde, and there are no metal objects such as pipe or the drill unit within 20 feet.

Turn the receiver on and press and hold the depth and up arrow keys until calibration is complete. You can verify the calibration by moving the receiver to 15 feet away. If the display doesn’t show the correct reading, calibrate again.

Perform the beacon’s diagnostic checks and signal strength tests before deployment. Keep a spare transmitter on the job site to prevent downtime.

Check for Active and Passive Interference

Active interference is anything that submits a signal, such as invisible dog fences and power lines. Passive sources weaken or distort the signal from the sonde and include chain-link fences or rebar.

Before drilling, walk the path of the bore with the receiver switched on and look for potential interference. If you receive a signal, the higher it is, the more active interference there is.

Monitor the Telemetry During Use

Once drilling begins, a person walks the bore path with the receiver, which sends the telemetry data from the sonde back to a monitor on the drill rig. Based on the information displayed, the operator can adjust the drill to stay on course.

If the temperature rises beyond 95 degrees Fahrenheit, stop drilling to prevent overheating and damage to the sonde. Pull the drill back a few feet into cooler dirt.

A heat-affecting temperature dot will identify if components within the sonde are damaged due to heat. This visual cue will help when buying a used sonde transmitter.

Between drilling operations, perform regular maintenance. Check for oxidation, the integrity of the seals, and for drilling fluid in the battery compartment. This will help your used HDD equipment last longer.

Why, When, and How to Use a Sonde Transmitter Properly

A sonde transmitter is an integral part of any HDD drilling equipment. If you calibrate before drilling, watch for interference sources, and check the data it sends, the sonde will help your bore be accurate.

For more helpful articles on drilling or utility equipment, check out the rest of our blog.