Unlikely. The interference from the electric motor just worked because analog TVs used to recieve a (weak) analog signal via antenna. That doesn’t apply to the HDMI/RF connector. I suspect the CRT might not be able to deal with the HDMI converter’s line frequency. Also., I don’t know if the CRT has a separate composite input - if you go in via the antenna input be sure to set the converter to RF, not to composite output if possible. Composite and RF signal are not the same.