Abstract: A method for measuring a water condition such as temperature or speed proximate a desired location in the water such as near a fishing bait. The method comprises positioning a sensor for the condition near the location which provides a signal proportional to the condition, modulating a high frequency radio signal using the electrical signal, transmitting the modulated signal along a conductive line, detecting the modulated signal and using the detected signal to drive an observable indicator of the condition. The invention also includes an apparatus for practicing the method of the invention. The apparatus includes a sensing means, a modulating means, a transmitting means, a detecting means and a means for converting the detected signal to an observable indication of the condition.