Strangely, mobile rigs are the one area of ham radio where there’s not a lot of homebrewing, although there is an active community that repurposes old UHF and VHF business band radio for ham use.

Buy CB rig, install rig, start talking on channel 19 ... on the 2-meter VHF band from 144 to 148 MHz, or on the 70-cm UHF band from 420 to 450 MHz. FM is generally the mode of choice in these ...