An automatic phasing system for satellite communications earth stations high power amplifiers

An automatic system is described which combines the outputs of klystron or TWT high-power amplifiers; the system accomplishes phasing by phase locking the carriers out of one of the transmitters to the other unit's output by means of a standard phase detector circuit. This will minimize the need for field adjustments in combined TWT amplifiers following tube replacements, and will also allow for the combined operation of two klystron amplifiers. The development of an equivalent 6 kW air-cooled, 6 GHz klystron high-power amplifier using two standard 3 kW units is being investigated.