MiniSport Laptop Hacker - Vol 11, 5 Apr 1993
Copyright(C) 1993 by Brian Mork.

>>> CONSERVING ENERGY
Your MiniSport runs on NiCad batteries.  It is good to regularly let these
run down until you get the red POWER light flashing and beeping.  That
deals with the well-known "memory" effect of NiCads.  However, if you let
the NiCads stay in this discharged state, the Lithium batteries ($2 each,
CR2430, RS 23-166) will go dead *fast*.  The NiCads, even fully charged,
will eventually be discharged from backing up the RAMdisk.  From experi-
ence, I know that 2 months of inactivity will fully discharge both the RAM-
disk and the Lithium batteries.

There are a lot of power management techniques specific to the MiniSport,
and that's what the rest of this section will be about.  The effect of
choosing the lower-power option on each of the following independent areas
is cummulative.  By managing my batter energy, I regularly get 4-plus hours
of "on" time before the power light starts blinking.  That's 4 hours in my
work room, not in the manufacturer's literature!

1) The mechanical movement of the floppy drive is by far the worst power
   draining activity.  Limit it's acitivy to the minimum possible.  I use
   my floppy drive to back up an afternoon's worth of work, not to perform
   that work.  Each time the floppy drive is accessed, picture 5-10 minutes
   of NiCad charge going away.
2) When you're not using the computer, turn it off!  The computer only
   takes a few seconds to boot up from a power-off state.  If you're look-
   ing up some documentation or twiddling some knobs on other equipment for
   more than a minute or two, there is little reason to leave it on.  Turn-
   ing off your computer as you step away from the desk is a practice
   you'll have to get used to.
3) Turn your screen to minimum brightness.  If you're in a bright room or
   sunlight, you may get by with the brightness turned all the way down.
   In the SETUP menu (CTRL-ALT-INS, or ESC during bootup) you can set a
   timer to automatically turn the screen off after a few minutes.  Set the
   timer to the minimum value.
4) The I/O ports (COM1, COM2, LPT1) can each be "turned off" even while the
   computer is turned on.  Once again, check the SETUP menu or use the MA-
   CHINE command at the DOS command prompt.  If you won't use the ports for
   the next few hours, turn them off!
5) The MiniSport can be set to execute instructions at a fast speed or a
   slow speed.  The cost of running at fast speed is greater use of energy.
   For a portable, that means less battery life.  Again, use the MACHINE
   command or the SETUP menu to choose the SLOW speed unless you need the
   fast speed.
     If you do select the FAST speed, the biggest waste of energy occurs
   when the computer makes an I/O request to the disks.  It's silly to let
   the computer do nothing very fast while it waits for the disk!  Zenith
   recognized this and provided a SMART option for the clock speed.  With
   this setting, the computer runs at FAST except during disk I/O, at which
   time it automatically goes into the SLOW mode.
     One last thought: there's a third, even easier, way to switch between
   the speed settings.   The SLOW and FAST selections on the F3 and F4 key
   provide this exact function.  Use SETUP to choose the slow speed and
   then only if you need it, press the FN-F4 (fast) key.  Because it's so
   easily available, I select SLOW at the SETUP menu and choose FAST from
   the keyboard only if I feel I need it.
6) Keeping the RAMdisk saved when power is off uses energy, but because I
   use it like a small hard disk, I accept that sacrifice.  If you're look-
   ing for maximum time between recharges, USE the SEUP menu to select not
   to keep the RAMdisk saved.

73, Brian Mork (Opus-OVH)          KA9SNF@wb7nnf.#spokn.wa.usa
                                   Internet ka9snf@jupiter.spk.wa.us
                                   6006-B Eaker, Fairchild, WA 99011