Li {\it et al.\/} (2024) reported a 4.605 day period in the repeating FRB 20121102A in addition to the previously reported 157 day modulation of its activity. This note suggests that the shorter period is the orbital period of a mass-transferring star orbiting a black hole, possibly of intermediate mass, and that the 157 day period is the precession period of an accretion disc around the black hole. The mass-losing star must be evolved.
@article{arxiv.2405.03721,
title = {Orbital and Precession Periods in Repeating FRB 20121102A},
author = {J. I. Katz},
journal= {arXiv preprint arXiv:2405.03721},
year = {2024}
}