What is a sonde transmitter? The basics of modern transmitters.
A sonde transmitter (probe) is a an electronic device that fits inside the drill head housing and transmits a magnetic field to your Ditch Witch locator or DigiTrak locator. In horizontal directional drilling, sondes are used to pinpoint exact location of the drill head during a pilot hole process. Different transmitters use single or multiple radio frequencies to provide drillers with information like depth, pitch, temperature and battery life. The most common power source for sonde transmitter are CC style batteries. Some transmitters also utilize cable inside drill pipes to power the sonde.
The basic function of any sonde is to guide drill operator during a pilot hole drilling. Once the sonde housing is below ground, locator operator walks above ground providing location, depth and other transmitter telemetry back to remote display on a drilling rig. This allows operator to keep drill head along the pilot bore path and exit at predesigned point.
All transmitters are equipped with an internal digital thermometer and physical temperature dot to prevent your sonde from overheating. It is not recommended to reach temperatures above 95° F.
In case of excessive overheating, drilling should be suspended to allow your sonde to cool down. The best practice is to stop drilling and retract the sonde housing couple feet back. If temperature exceeds 104° F, the temp dot will change color from white to grey or black color. Black dot indicates that the transmitter has been exposed to high heat and some components have been damaged. Furthermore, removed or black temp dot also voids transmitter warranty. The most common reasons for overheating are insufficient mud flow, harsh soil, and blocked jests. To avoid overheating, practice proper drilling techniques and best practices.
DigiTrak or DCI manufactures several different sondes with multiple frequencies, ranges and telemetry options for different models of DigiTrak locators. Some legacy HDD locating systems include models like DigiTrak Mark III, IV, V, Eclipse, SE and LT. More modern models include DigiTrak F5, F2 and F1 systems.
In order for you receiver to communicate properly it must be match with correct sonde transmitter, as well as, matching regional designation. A region number can be found inside the globe icon on your DigiTrak transmitter and inside the same icon on a display of your receiver or remote display.
Ditch Witch and Subsite Sondes
Ditch Witch or Subsite transmitters also come in different sizes, ranges and different features. The most common Ditch Witch locators include Tracker 750, Tracker 752, and TK series. Appropriate sonde should be paired with proper locator model to receive correct telemetry data. Subsite 86B and Subsite 88B sondes send depth, roll, temperature and battery level back to your locator.
Calibrate your sonde transmitter
It is recommended to calibrate your sonde or beacon before each job. Skipping calibration can result in improper depth reading and failed pilot hole drilling. Only depth estimation is affected by calibration. Roll, pitch, left/right deviation, temperature, and battery status are not affected.
For complete list of drilling terms, expressions and jargon, be sure to check the most complete Directional Drilling Glossary and Terminology.
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