159.12   PROHIBITED SIGNS.
All signs not expressly permitted under this chapter or exempt from regulation in accordance with the previous section are prohibited in the City; such signs include, but are not limited to:
1.   Beacons;   
2.   Pennants;   
3.   Strings of lights not permanently mounted to a rigid background, except those exempt under the previous section; and   
4.   Inflatable signs and tethered balloons, except those waived by the City Administrator for display during City sanctioned events.