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

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 $\mu$TCA.4-based system, which can be developed further. In this presentation, we will report the details of the upgrade, as well as the feedback and feedforward adjustments.