Hi Joe
On (05 Sep 97) Joe Kron wrote to Alec Cameron...
 JK> I guess some of the reasons you list for AC still persist even when one
 JK> produces one's own power locally. 
My message was so long ago, I forget what I said. But I probably missed 
ese-
AC is used on many DC driven railways. The 600 or 1500 volt incoming, changed
to AC then applied to EITHER AC drive motors, or subsequently rectified thru
thyristors to provide smooth, ultra- low loss speed control of common DC
traction motors. The so- called Chopper transmission.
AC is also used as the power supply for many dry cell driven Walkman radios,
portable TVs etc: once again, the dc is converted to AC then back to dc 
gain,
because in the AC mode clever and useful thing can be done to alter and
regulate, the voltage. For example, the power amplifier stage may operate at
5v plus minus 5%, even though the dry battery slides from 1.5v/ cell [new] to
0.8v/ cell [exhausted].
The latter is good HOMEPOWER philosophy, because the disposable battery may
work for weeks longer than it used to. Something from "nothing"!
Cheers................ALEC
... Wunce i coodn even spll ingineer. Now i are wun!!
--- PPoint 1.92
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