Alternators are interesting devices. Today they have internal
regulators which control the field current to regulate the output voltage.
They have to charge batteries and operate lights and other equipment even
at idle. Alternators are limited mostly by the heating of the
stator windings which is current squared times the windings resistance. If
you do away with the regulator and provide your own excitation
to the field ( rotor) you can get much more output voltage. You can get 120
or more volts DC, or AC if diodes are removed from them and draw the same
current. This
used to be done years ago when folks wanted to run their electric chain saw
or skill saws off of their car's alternator. They had universal
winding motors. Also the silicon rectifiers had sufficient reverse
polarization to handle 120VDC output. They probably use Schottky today
which may not.
By the way, they do have quite a high frequency output.
73
Bill wa4lav
At 05:41 AM 8/27/2012 -0700, Jim Hoge wrote:
>Don,
>
>That's the exception. I've heard the claims from some who run stock that
>they are capable of such numbers. I had a boss who was an ardent cber ask
>me to fix his mobile solid state amp. I said I would take a look at it.
>After all, I was curious. I had no intention of fixing it for him though.
>The math said there was no way he could get 500 watts out with only a 20
>amp fuse in the 12 volt supply lines, even IF the amp ran at an efficiency
>of 100%. Who only knows how over driven the amp must be and I'd hate to
>see the spectrum analyzer under such conditions. BTW, it was a blown
>transistor on the input side (2x4 configuration). Gee, I wonder how that
>happened. I gave the amp back to him and said I couldn't find the problem.
>
>
>Gotham couldn't hold a candle to some of these guys.
>
>73,
>Jim W5QM
>
>
>
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