As we often drove in unfamiliar areas in the UK and Europe, I found that a sat nav was an absolute necessity. To facilitate this I made and fitted a 6 to 12 volt converter. I have been told that a sat nav will run on 6 volts, but I am not convinced, especially with our erratic supply in the car.
For more information on garmin Sat Navs see below:
:https://www.austin7.org/Technical%20Articles/A%206v%20to%2012v%20Converter/
As commercial units became available I have uprated the unit. The latest converter is powerful enough, at a nominal 10 amps, for all the 12 volt devices we are likely to use. A useful addition is a charging adaptor and voltage display.
DIGITEN DC 6V 5-11V to 12V 10A Step up Converter
The converter, fitted inside the glove pocket, has a heat transfer pad under it to help with cooling. The 6 volt supply comes direct from the battery using the cable and plug installed for charging. A fixed cigarette lighter socket, under the dashboard has completed the set up. All fixing holes are in unobtrusive places and will not show if the unit is removed,
BBM69 