The output characteristics of a linear array of oscillators are discussed. By arranging the output frequencies of each oscillator to give a spectrum of equally spaced components, a mode-locked system results, thereby producing short, high-power RF pulses. Promising results from a linear array of up to five elements are presented, with good theoretical agreement. The results presented suggest that it may be possible to generate high-power RF pulses with high-pulse repetition frequencies using planar arrays of devices. This quasi-optical array architecture is expected to scale up to the Terahertz frequency range using suitable devices.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>