A method and arrangement for mud telemetry having components of a wellbore casing, a combination rotor stator positioned inside the wellbore casing, an uphole detection arrangement configured to sense increases and decreases in pressure, a valve actuator, a valve configured to be actuated by the valve actuator, the valve configured to convey a fluid from an inside of the wellbore casing to an outside of the wellbore casing and cause a decrease in fluid pressure in the wellbore casing, and a downhole tool configured to measure at least one formation parameter.