Because of the increased reliability required of rocket systems in their more recently assigned missions, previously acceptable design features must be reappraised ad refined. In the region of rocket engine system stability, the probles is centered in two areas, the combustor and the propellant feed system The principal interest of this paper lies in the coupling that occurs between the feed system and combustion dynamics, often termed a "buzzing" instability then the dymics are characterized by periodic pressure oscillations in the range of 200 to 1000 cps appearing in the combustion chamber and' the feed system.