Author: Bravo, B.
Paper Title Page
WEPFI049 CoStub: A 6 1/8” Coaxial Short Circuit using Stubs 2809
  • B. Bravo, F. Mares, F. Pérez
    CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
  ALBA is a 3Gev synchrotron light source located in Barcelona and operating with users since May 2012. The ALBA storage ring uses six room temperature cavities; each one fed by two 80kW IOTs amplifiers at 499.654 MHz. The power of the pair of transmitters is combined by a cavity combiner, CaCo. The two possible operation modes of CaCo at high power have been tested. The symmetrical mode (two IOTs feed the CaCo symmetrically) works properly and without presenting any problem. But in the asymmetrical mode (one IOT feeds the CaCo and the other is keeping passive) a standing wave is created between the passive IOT and Caco, provoking a large voltage in the gap of the passive IOT that broke the ceramic. A new device, CoStub (coaxial stub), to short circuit the coaxial waveguide of the passive arm and protects the passive IOT has been built and successfully tested. This paper presents the design details and the low level and high power test of this device.