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the entire amplifier including its case are kept at +45 V in order to avoid the secondary emission of electrons by the collector.
2.5 The R. F. System.
In Fig. 15 a block diagram for the R. F. Sy.stem is given. As can be seen from this diagram the system is essentially the following. A Sperry SRL-6 Klystron oscillator, which is rated at 5 watts at 2617 megacycles, drives two Sperry 8529 Klystrons, which are rated at 100 watts each, through a power and phase splitter. This "phase-splitter" is a coaxial line structure with a moving feed point. The line impedances are such as to get equal power division, and the movable feed provides variable phase. The output of the 8529's feeds two wave guide sections which are in turn coupled by means of probes to coaxial lines. All of the lines of the system are provided with stub tuners and slots for standing wave detection. In operation it is necessary to adjust all stubs for unity standing wave inthe lines. The coaxial lines are inductively coupled to the cavity. In Fig. 9a one can see one of the coupling loop sections lying just to the left of the cavity. These loops are operating in time and space quadrature and thus yield the rotating magnetic field. The entire R.F. system is visible in the foreground of Fig. 7. A better view of the coaxial coupling lines is shown in Fig. 8.
The power supply for the SRL-6 Klystron was made from two warsurplus dynamotors placed end to end and driven as generators by an external one h.p. motor. This arrangement gives two 1000 volt at 300 MA. sources as well as two 28 V d.c. sources at 10 amp. each. One of these
