Abstract: An accelerometer module is supported within an interior passage of a transmitter housing of a transmitter that is itself receivable within an inground housing of an inground tool to perform an inground operation which subjects the transmitter to mechanical shock and vibration. An accelerometer housing of the module includes an exterior periphery that is receivable in the interior passage of the transmitter. A resilient damping foam can be supported to dispose the foam between the accelerometer housing and the transmitter housing such that the foam cooperates with the accelerometer housing to form a complex mass-spring-damper system that exhibits a resonant frequency which is controllable. An accelerometer cartridge of the module can include a mass that is at least five times the mass of an original accelerometer cartridge. In one feature, the accelerometer cartridge can include a mass of at least 20 grams for a one inch diameter transmitter housing.

Abstract: An inground housing supports a transmitter for receiving electrical power from a battery. The transmitter transmits at least one signal using at least two different transmit power levels for at least one of locating the transmitter and characterizing an orientation of the transmitter. Based on detecting the battery voltage, the transmitter selects one of the transmit power levels. Transmitter output power can be controlled based on one or both of signal gain and duty cycle.

Abstract: An inground housing supports a transmitter for receiving electrical power from a battery. The transmitter transmits at least one signal using at least two different transmit power levels for at least one of locating the transmitter and characterizing an orientation of the transmitter. Based on detecting the battery voltage, the transmitter selects one of the transmit power levels. Transmitter output power can be controlled based on one or both of signal gain and duty cycle.

Abstract: An inground housing supports a transmitter for receiving electrical power from a battery. The transmitter transmits at least one signal using at least two different transmit power levels for at least one of locating the transmitter and characterizing an orientation of the transmitter. Based on detecting the battery voltage, the transmitter selects one of the transmit power levels. Transmitter output power can be controlled based on one or both of signal gain and duty cycle.

Abstract: An inground housing supports a transmitter for receiving electrical power from a battery. The transmitter transmits at least one signal using at least two different transmit power levels for at least one of locating the transmitter and characterizing an orientation of the transmitter. Based on detecting the battery voltage, the transmitter selects one of the transmit power levels. Transmitter output power can be controlled based on one or both of signal gain and duty cycle.

Abstract: An inground housing supports a transmitter for receiving electrical power from a battery. The transmitter transmits at least one signal using at least two different transmit power levels for at least one of locating the transmitter and characterizing an orientation of the transmitter. Based on detecting the battery voltage, the transmitter selects one of the transmit power levels. Transmitter output power can be controlled based on one or both of signal gain and duty cycle.

Abstract: A device is described for use in performing an inground operation. An accelerometer is supported by the device for generating accelerometer readings that characterize the inground operation subject to a native temperature drift of the accelerometer. A set of compensation data is developed and stored for use in compensating for the native temperature drift. The compensation data is applied to the accelerometer readings to produce compensated accelerometer readings that externally compensate for the native temperature drift to yield an enhanced thermal performance which is improved as compared to a native thermal performance of the accelerometer. A seven position calibration method for a triaxial accelerometer is described. An air module is described which isolates the accelerometer of the device at least from a potting compound that at least fills otherwise unoccupied volumes of the device interior.