An approach to a pneumatic ventilator utilizing compressed air as the air source and common solenoid valves for control of an automated breathing cycle is presented. A simple computer program was developed for control of the breathing cycle based on two control parameters: the number of breaths per minute (BPM) and the exhalation to inhalation time ratio (EI ratio). An optional pressure sensor was used to monitor the face mask pressure during automated ventilation of a 43 year old 185 pound male human volunteer. The system was capable of achieving automated ventilation within acceptable constraints: BPM = 8 - 40, EI ratio = 1:1 - 1:4, positive end-expiratory pressure (PEEP) = 0.07 - 0.2 PSIG, and maximum pressure < 0.57 PSIG. Data suggests that solenoid valves with a flow coefficient (Cv) = 0.6 - 1.7 are suitable. The total cost of the parts required to build the system is approximately $700 USD not including the PC and air compressor used to run the system. Once parts are acquired this system can be assembled within a day or less. Parts lists, designs, and download links to the computer software used here are provided open source.