Oh, my...
Because John''s warning is warranted (and if ignored, sometimes expensive), let''s break this up into categories:
For low-amperage (<1 amp, usually) DC charging needs (shaver, electric tooth brush, AM/FM
radio, CD player, etc.), the easy answer is to buy a DC multi-voltage adapter right off the
Radio Shack shelf. Only a few bucks, it comes with different size connectors (with adjustable polarity - don''t forget to note polarity when plugging in) for each voltage. 12V in, your V of choice out.
For motors that use 12V DC even if rectified from AC (e.g. hand drill or palm sander; check internal voltage on the equipment), use onboard DC. Motors are forgiving...
For electronics, which can indeed by sensitive to voltage spikes (what happens if you use your house bank to start up your engine?), you have two options:
1. Most of these devices originally come with a power cube/adapter meant to be plugged into an AC outlet and which changes AC to DC of the correct V. Many boats end up collecting a bag of these things, which over time become quite useful for unexpected uses. You can purchase a small, inexpensive
inverter either at Best Buy et al. or on the web (I''m coveting a 350VA unit right now that''s only $35 and weighs 2 pounds), wire that in direct to your house bank via a switch/breaker, and then use these power cubes as you need them. And/or...
2. For dedicated non-stop use (a laptop is the best example), you might not want the electrical overhead of running an
inverter. E.g. altho'' "my" coveted 350VA unit has an ''on/not used'' amp draw of 100 milliamps, it''s electrical overhead when servicing a device is higher. In this case, you can purchase & use a dedicated DC power adapter, which can indeed provide volatage much higher than the 12V source. But one caution: if you have a
SSB aboard, it''s rf output will screw with the adapter''s electronics and bugger the laptop''s (or whatever) performance, so getting a good adapter is important. For laptops, an adapter should either be rated for in-flight airline use or be built with
SSB use in mind. (I can recommend an excellent source; cost is about $75).
I''m sure there are many other methods out there; this is one of those areas where folks get REAL creative...
Jack