(a) Every projecting sign shall be securely attached to the building wall, structure or suitable metal posts located within the lot lines by iron or metal anchors, bolts, supports, chains, stranded cables or steel rods. The minimum size cable for head and side guys or iron wire, number fourteen American Standard, trade size. No such sign shall be supported from the street or sidewalk.
(b) Nothing herein contained shall be deemed to prohibit the erection of a sign on a lawnstrip which is at least eighteen feet in width, between the curb and the nearest edge of the sidewalk, so long as such sign is a center-post type, no larger than four feet in width by eight feet in height and so long as the post is not less than eight feet distant from both the curb and the inside edge of the sidewalk, and not less than twenty-five feet distant from the curb of the nearest intersection street. (1964 Code § 701.18)