High Resolution Digital Time Base

A time base has been developed to supply general timing signals for the Cornell Electron Storage Ring, including beam bunch transfer triggers and beam detector triggers. The system consists of 8-bit counters and digital phase shifters of 8-bit resolution, under control of a data bus tied to the CESR control computer interface. The counters use conventional Schottky TTL techniques at a clock rate of 23.8 MHz, and the phase shifters are based on an ECL phase-locked loop, giving a resolution of 150 ps/LSB, jitter of 50 ps, an offset T.C. of 10 ps/°C, and a gain T.C. of 100 ppm/°C.