A Precision 10-Hz Clock for Military Electronic Timers

摘要

A precise clock suitable for providing pulses to counting circuits in an electronic timer is described. The clock consists of an accurate 810-Hz twin-T oscillator, a wave shaper, and four stages of ternary dividers. Also described are circuits to inhibit the dividers from giving clock pulses until the counting circuits are ready to accept them and to set the dividers initially to compensate for the power supply rise time. The clock exhibits a frequency stability of plus or minus 0.05 percent over the temperature range-55 to +71C. The clock is expected to maintain this stability after 30,000-g linear acceleration and during 35,000-rpm spin. Limited air gun and field tests indicate that the clock will maintain its stability in this environment. (Author)