If the cable end has 13 splines it fits the SCR-183/283, RU units. The outside diameter of that cable end is .400. The retaining nut is larger also than for the SCR-274-N, AN/ARC-5, etc. I do not have the specs for the MN-26 and other radio compass units. Those cables are larger than the AN/ARC-5 cables which ends are .330 inch in diameter, with, I believe, 24 splines.