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From: john@frog.UUCP (John Woods)
Newsgroups: sci.electronics
Subject: Re: Power Inverter suggestions?
Message-ID: <1661@frog.UUCP>
Date: 21 Jul 89 22:38:00 GMT
References: <4398@eos.UUCP>
Distribution: usa
Organization: Misanthropes-R-Us
Lines: 26

In article <4398@eos.UUCP>, jbm@eos.UUCP (Jeffrey Mulligan) writes:
> 
> I am interested in building a 12 v dc to 120 v ac power inverter.
> 
> I have only a vague idea of how such a thing might be done:

There are two basic kinds, depending on how clean you want the output power
to be.  Some devices don't mind a 120V square wave, in which case you can
just interrupt 12VDC at 60cps, send this through a backwards 120V/12V AC
transformer, and you're done.  This can be done with switching transistors
or with actual mechanical switches (as in the old vibrator power supplies
for mobile operation of tube style radios).

Other devices really, really want a sine wave.  The easiest way is to build
a 60cps oscillator and send that through the transformer, but the most obvious
ways of doing that dissipate a LOT of heat in your transistors and are not
horribly efficient.  There are more efficient ways to go about it, but alas
my references are at home and I'm not...

The summary answer is, what do you want to use the inverter for?

-- 
John Woods, Charles River Data Systems, Framingham MA, (508) 626-1101
...!decvax!frog!john, john@frog.UUCP, ...!mit-eddie!jfw, jfw@eddie.mit.edu
    People...How you gonna FIGURE 'em?
    Don't bother, S.L.--Just stand back and enjoy the EVOLUTIONARY PROCESS...