Heat transfer from electron tubes at high altitudes and high ambient temperatures

THIS paper contains the results of a series of temperature tests conducted on a 6AQ5 beam power tetrode at full rating at simulated altitudes and ambient temperatures. The effects of altitude, shielding, tube position, and ambient temperature on temperature rise of the hottest spot of the glass envelope are shown. A few measurements were made of the effect of surrounding a single tube by a cluster of other tubes of the same type and rating. The tube was not delivering any output.