Abstract: An apparatus for automatically calculating the fall height of the ram of a pile driver is disclosed. The apparatus includes a device for converting the sound created by each blow of the pile driver ram into an electrical signal, a first circuit for converting signal into a pulse and a second circuit for converting the time elapsed between the pulses for consecutive blows into a digital output representing the fall height of the ram for the blow corresponding to the latter pulse. The digital electronic circuit may also include circuitry for counting the number of blows in a sequence of blows and circuitry for determining the average fall height for the blows occurring during the sequence.