Specifications include, but are not limited to: Electronic Shielding – RFI Protection - A. Trucks will have 2-way, land mobile radio transceivers installed by Department personnel. Transceivers will operate in the high band at 700/800 (150 to 174 MHz and 700/800 MHz). Antennas will be mounted on the roof or highest plane surface of the truck. All electronic circuits, including but not limited to ignition, AM/FM radios, computers, emission controls, alternative fuel electronic controls, regulators and/or any equipment controls must be designed to prevent interference that could affect the Department transceivers. Vehicle’s electronic equipment must also be unaffected by the radio frequency energy generated by the (up to 125-Watt output) transmitter of the installed transceivers. B. Electrical system must be designed so that the vehicle must not degrade the 2-way radio receiver performance. The effective sensitivity of the BHF or 700/800 MHz FM receiver must not require more than 0.5 microvolts (-111 dbm) to produce 12db or greater SINAD. Effective sensitivity must not exceed 0.5 microvolts for all modes of operation which must include but not be limited to engine off, engine on (from idle to full throttle) and all vehicle systems. C. Truck may be tested by the Department upon delivery and must meet these RFI requirements. D. The Department currently utilizes multiple frequencies from 150-163 MHz and 700/800 MHz and will test RFI in these bandwidths. Department 2-Way Radio Antenna Bases and Wiring - A. Vendor must install a Department supplied, 2-way radio antenna base on the truck cab roof. Installation requires the drilling of an approximate 3/4-inch hole in the roof, securing the base, and running the coaxial cable to the radio mounting location in the cab. Placement should be in the center of the roof both front to rear and side to side, if a center brace is present moving forward or to one side is acceptable. B. Additional radio wiring instructions: a. The two-way radios mounted in the DOT trucks require an un-switched 13.6 VDC battery power connection with a 12-gauge wire, terminated in the housing above the windshield. Wire needs to be fused with a 20-amp fuse or breaker at the source. This power must be to a point which voltage will not pull down as the radio cannot operate with voltage less than 11.3 VDC. We also require ignition switched 13.6 VDC to turn the radio on when the vehicle is operational. This needs to be fused with a 4-amp fuse or breaker. This switched power must be able to sustain a 11.3 VDC or higher as the radio will not operate at lower voltages. This too must be terminated in the housing above the windshield...
