[Elecraft] Off-topic... electronics ?

[Tom Hammond NØSS]

John:

>I don't know of any other list with as knowledgeable a user base, so here
>goes....
>
>Is it possible to step up a DC voltage to a higher voltage (but lower
>amperage)?  I want to power a device that needs more than 12v from a 12v gel
>cell, but can't figure out how to do it.  Any pointers would be appreciated.

You can build a small DC-to-DC invertor, using an NE555 (timer IC). It 
concerts the 12VDC to a 12V square-wave and then runs it thru a voltage 
doubler circuit, which can then be rectified and filtered to obtain a 
higher voltage.

As I recall from a QST article of several years ago, there's also an IC 
which does this all in one step. Unfortunately, I can't recall which IC it 
was... something of a specialty IC though.

I think I can supply a schematic of the NE555 circuit if you are interested.

I used to use this ckt in a mobile NiCd charger I once built.

How much voltage AND currect do you need?

Tom  N0SS