Upgrade of low-level RF system for J-PARC linac RFQ-TS

Nakano, Hideto; Mizobata, Satoshi*; Futatsukawa, Kenta*; Fuwa, Yasuhiro   ; Fang, Z.*; Fukui, Yuji*; Sato, Yoshikatsu*; Cicek, E.*; Kitamura, Ryo   

The radio-frequency quadrupole test stand (RFQ-TS) was prepared for conditioning the spare RFQ in the J-PARC Linac. Additionally, the RFQ-TS is used for the development of accelerator components and the acquisition of beam parameters. The digital feedback system of the Low-Level RF (LLRF) in the RFQ-TS was previously using the discontinued cPCI system, which had been in use for 20 years since its development. In order to continue improvements of the RFQ-TS and to allow for future development, the system has been upgraded to use TCA.4-based system, which can be developed further. The cPCI system previously used as the digital platform for the DFB & DFF system in the J-PARC RFQ-TS LLRF system has been replaced with a TCA.4 platform. After optimizing the DFB and DFF settings on the digitizer, stable accelerator operation was confirmed following the platform change.