Rca Electrical Wiring Diagrams - FEDERAL SIGNAL/UNITROL TOUCHMASTER LIGHT & SIREN CONTROL Found this used unit out of a county emergency vehicle; it's seen some use, unknown condition, UNTESTED.. VMARSmanuals. The VMARS Archive. Index of Filenames. How to use this index. If you are using Internet Explorer, press ctrl-F then enter a keyword (e.g. the model of the equipment you are looking for) in the search box..