Low Voltage Cut-out Switch

Do you have an aux battery set-up in the vehicle? If your aux is set up properly it shouldn't drain the main.
The radio won't draw a lot of current on receive, but does use more on transmit.
I have left mine on for several days at a time without a lot of drop in battery voltage.
Cheers
Oskar

i might have missed something but why not wire it up to acc on the car.
will only work with ignition on then.—~‘¬‘¥•s’B

Louise you can buy a low voltage cut-out from KMart Auto for under $20
The brand is called Projecta
We have them fitted to all the tractors and vehicles
Great no more flat batteries

I have one of the units that 'VIOLA' mentioned. $20 from Kmart and I am very happy with it (no more flat battery when I forget to turn frig to gas !) - I plug it in line before the 3 way frig - it cuts out at 11.6 v (I haven't checked these figures !) - I am using a deep cycle battery as the car (Forester) doesn't require a lot of cranking power.
For the price of these units I imagine you could put one in line to any appliance that may be left on for extended periods ?

PS - I have mentioned this 'here' before - I have installed a 12v computer fan to frig heat sink, heavy wire direct from battery to frig, and covered frig with self adhesive foam backed foil (from Clark Rubber - I should ask for a discount from them for the amount of times I have metioned this)
These 3 mods have made a huge diference to the frigs performance !Subaru Forester
size isn't everything !

why not just turn off t eradio when you intend to leave the vehicle for a while??