Improvement of the low power RF phase stabilizer test circuit

Development of the low power rf stabilizer circuit has been continued at LEBRA, Nihon University. The problem of unstable operation of the test circuit was solved by the replacement of an asynchronous 12 bit counter, which was used for the estimation of the correction of the rf phase, with a synchronous one. A long transient time before the phase-locking in each rf pulse was considerably improved by the application of an automatic initial phase offset based on a feed-forward technique. However, the phase stability of the output of the klystron driving rf amplifier has been estimated to be ±0.6deg with the improved circuit, which is worse than the old result. (author)