Pasture Yield Instrument Using a Radio Frequency Bridge

A single unit grass‐meter has been developed to replace the twin transmitter‐receiver units which have been in use since 1958. In the new design a radio‐frequency capacitance bridge is mounted on top of a measuring head. Introduction of grass into the measuring head unbalances the bridge and the amount of unhalance, which is a function of the mass of the herbage, is indicated on a micro‐ammeter. Two ranges are incorporated so that sheep pastures with short grass and cow pastures with long grass can be measured.