In this installment of Ham Mobile Install, we will discuss powering options for your mobile radios. There are several options to explore, depending on the power of the transceiver and the amount of time it will be in use without the vehicle running.
The first and easiest option would be for very low power radios—say, handhelds or mini mobiles that top out at 20 to 25 watts. HTs can use their built-in battery or you can purchase a cable that powers the radio from the cigarette lighter. Sometimes these cables plug into the charger port and sometimes they are marketed as battery eliminators. Below is a cigarette lighter cable (KWD-PG-3J) for select Kenwood handheld transceivers.
Mini mobile radios rated at 20 or 25 watts typically come with fused cigarette lighter power cords and are safe to use in your car as they don’t draw too many amps from the cigarette lighter adapter.
The next option is to wire your mobile radio directly to your car battery. Run your transceiver power leads directly to your vehicle battery terminals and avoid any use of existing automobile wiring. The wiring used in most car power outlets is not designed to carry the high currents that a full power transmitter can draw and may quickly overheat and start a fire. In addition, you will probably pick up an abundance of electrical noise going that route.
The power leads will need to be routed through the vehicle’s firewall into the engine compartment and to the battery. In older vehicles, this is much more difficult to do and might require some drilling. Most modern automobiles have access ports through the firewall in different locations. They are usually plugged with a rubber grommet and aren’t always in the most convenient locations. You may have to go searching under the hood and/or under the dashboard. The access ports might even be behind engine components or under carpet or trim.
The last option needs to be considered if you plan on operating from your car for long periods of time while it is stationary. You don’t want your car running for hours, wasting gasoline. You also can’t run for hours on battery power with the car off without depleting your battery.
The thing to do in this case is to have another large battery that can be recharged externally. This battery can be stored most anywhere convenient in the vehicle.
Lithium Iron Phosphate (LiFePO4) batteries, like those from Bioenno Power, have become a reliable energy storage solution for ham radio operations. Unlike traditional batteries, LiFePO4 batteries offer longer lifespans, better thermal stability, and higher energy density, making them ideal for amateur radio where consistent power is crucial.
Questions? Share them in the comments below or email me at KE8FMJ@gmail.com.
