RDP Electronics can now supply a special spring return LVDT for applications such as measuring rapidly moving targets. Up until now high frequency measurement applications have depended on using unguided or captive type transducers as spring return versions have not been able to reliably follow the movement being measured. RDP has now developed special transducers combining very high spring force with a very low mechanical mass to achieve a frequency response of ±2mm in the order of 100 to 1000 Hz. These special transducers now offer a convenient solution for tracking fast moving targets in situations where it might not be possible to physically mount the armature on the target.