Well ok ... let's apply a testing paradigm or "if you could choose only one
voltage, what would it be" to arrive at an answer ... how about 16 -11 = 5,
divided by 2 gets you 2.5, and adding that to 11 gets you 13.5 ... only 13.8
+/- a tad is more like a real world DC to DC output :-)

"Doug Dotson" dougdotson@NOSPAMcablespeedNOSPAMcom wrote in message
...
A VHF doesn't need regulated DC. They are designed to work off of
any reasonable voltage between 11 and 16.

"bowgus" wrote in message
...
If you use a DC to DC converter, then you know you will be getting a
regulated 12 Volts (or maybe 13.8 for the VHF???) ... just get one with
an
appropriate power output ... i.e., no need to spend big bucks for more
power
than you need. I myself would go with a converter ... that way the VHF
is
guaranteed to work.

"Nigel" wrote in message
...
I have a 24v electrical set up on my boat, but need a 12v supply for my
VHF
(amongst other things). Is there any reason why I can't just run a 12v
supply from just one of a pair of batteries, or do I need to use a
24v/12v
converter. I release this will draw charge from just one battery , but
won't
the other just top it up and there by drain them both equally
Thanks