The purpose of this project is to produce a low field magnetic sensor that has a high signal to noise ratio and that can eliminate unwanted resonances brought about by losses in the measurement system. The sensor in question will be utilized for logging down-hole oil and gas reservoirs so it has to be accurate. The sensor component which will be modified is the magnetic core. It will be used along with a coil as an antenna to send radio frequency (RF) pulses used to characterize underground formations. Hence, the magnetic core will be improved on in order to reduce hysteresis losses, eddy current losses and anomalous losses. In addition, a uniform external magnetic field generator will be designed for the measurement setup to accurately analyze the antenna’s response. Besides this, other sources of noise or interference may be investigated. Finally, a user defined interface to operate the measurement setup and, a program to detect and plot resonant frequencies will be implemented.