6V positive to 12V negative help

[41Joe]

I was on eBay and I saw this little item:
http://www.ebay.com/itm/Ford-Model-...ash=item54391e3923:g:aWcAAOSwT5tWKXUh&vxp=mtr
I hope that link works. I remember seeing a few posts back about adding a way to charge a phone or run a modern radio on a 6V positive ground car.
Sometimes items like this make me wonder how well they actually work. It sounds like one of those too good to be true scenarios.

 

[flatheadmurre]

A DC-DC boost converter is a coomon device, really simplified it works like if you let your car charge a battery and then hook it up in series with your system to double the voltage.
But instead of a battery its an inductor and it does it several times a second.
What you gain in voltage you loose in current so if you need 12v 3A you need atleast 6v 6A to make it happen.

 

[D. Jones]

Bought one a year or two ago and hooked it to the cigar lighter in my pickup so I can run the Garmin and charge the wife's phone, it also runs my portable CD player so we have music to cruise by.

 

[Sanddoc]

http://www.how-to-build-hotrods.com/6v-to-12v.html