DS3800HHTB is a highway transmit card developed by General Electric. It was created by GE as part of the Mark IV series of turbine controllers. Over the years, the Speedtronic Mark series has evolved into the Mark IV system, which is a descendent of the Mark I and Mark II series. The Mark series has been used to control all elements of turbine operation, including safety since the creation of the Mark I system in the 1960s. The Mark IV system is the culmination of years of automation innovation, refinement, and improvement.