Abstract: An apparatus for transcutaneous stimulation comprising: a pulse generator operative to generate repetitive pulses exhibiting a pulse width of 25-60 microseconds, a consistent pulse rise time of no more than 5% of the pulse width and an inter-pulse interval of between 0.1 and 3 milliseconds; an intra-group modulator producing modulated pulses exhibiting an amplitude of between 50% and 100% of a maximum modulated pulse amplitude in a generally increasing manner, the modulated pulses defining a group of pulses, the intra-group modulator being further operative to modulate the pulses to exhibit an amplitude of no more than 25% of the maximum modulated pulse amplitude for a predetermined time period between successive groups of pulses thereby creating a pulse train; and an output modulator modulating the pulse train to produce output pulses exhibiting an amplitude of between 50% and 100% of a maximum according to a predetermined repetitive waveform.