• M. Wendt, C.I. Briegel, N. Eddy, B.J. Fellenz, E. Gianfelice-Wendt, P.S. Prieto, R. Rechenmacher, D.C. Voy
  Fermilab, Batavia, Illinois
• N. Terunuma, J. Urakawa
  KEK, Ibaraki

To achieve a low vertical beam emittance at the KEK Accelerator Test Facility (ATF) damping ring, the BPM read-out system is currently upgraded with new high resolution electronics. Based on analog and digital down-conversion techniques, the upgrade includes an automatic gain calibration system to correct for slow drift effects and ensure high reproducable beam position readings. The concept and its technical realization, as well as preliminary beam study results are presented.