Battery connections

An increasing amount of my amateur radio activities these days is done from the car. It allows freedom of location - giving access to mountains and coasts where very substantial environmental gain is available - and an escape from modern RFI sources.

For anything other than a few Watts, though, a new, separate power supply from the car's battery is required. First of all, make sure you put in appropriate inline fuses near the battery for both lines, and use cable gauged suitably for your highest expected output. Getting through the bulkhead is usually very simple, requiring a pointy pair of scissors or similar to punch a small hole through the rubber gasket where the car's wiring loom passes into the 'cabin'.

Bottom, battery-facing sides. Remarkable amount of dirt/corrosion.

Upper side. Cleaner, but still not very good.

 

I scrapped my old runaround this week, and so was removing the 12V supply lines for the radio to be reused. The amount of corrosion and dirt that had developed at the contact points was quite surprising, and potentially a source of poor contact and performance.

So, in installing the wires with new connectors on my other car, I made sure this time to place plenty of aluminium conductive grease (most readily available as 'ConductaSeal' by Innovantennas, £7.95 at time of writing) on the posts of the battery before installing the connections, and then some more on top and only then placing the nut on top, whereupon I added more grease over this.

Based on my experience with a Yagi that was out in the sea air and hurricane winds for 8 years and which made use of this grease, I fully expect bright, shiny, uncontaminated contacts the next time I remove them!