In Machine Recharging

The Model 100's use as a true portable is made possible thru the use of
pen-lite batterys (4 AA cells).  The economics of battery replacement quickly
establishes the practicality of rechargable (nicad) battery use.  This requires
purchasing a battery recharger and demands that the batterys be removed from
the M100, placed in the recharger, charged, and then be replaced in the M100. 
The savings realised thru using rechargables is significant in realised savings
to justify this inconvience (the alternative requires battery changing as well
plus the trips to the store regularly for new batterys).
	However, this trouble can be avoided by converting the machine to
on-board recharging.  The following method was discribed here on the message
board about a year ago and has been used trouble-free for that time by a number
of the "Early-Siggers".   The cost is under $1.50 (not incluing nicads),
requires no soldering, can be completed in less than 10 min., and will save you
the cost of a recharger as it uses the M100s own powerpack for the charging. 

  The following  is a copy of Dr Laurence D. Preble's message of Aug. 28, 1983.
.
I have discovered an interesting way to avoid the constant replacement of
batteries in my 100.  The following modification requires no soldering. 
Required accessories:
   1. (1) 10 ohm resitor (1/4 watt) 
          RS 271-1303 5/$.39
   2. (1) 1N914 silicon diode or equivalent
          RS 276-1122 10/$.99
      (4) AA NiCad batterys
          RS 23-125 2/4.49 (2 pcks needed)
.
   PROCEDURE:
      (A) Install NiCads
      (B) Open case. (Remove four phillips-head screws in bottom, then press in
on the sides of the black portion of the case just foward of the buttons to
release case-securing catches, and lift off top --and turn it face down next to
bottom.)
      (C) Unplug flat ribbon cable which attaches LCD display to main circuit
board.
      (D) Locate wire from AC adapter recepticle.  Note that 3 wires go from
the receptical to a small plastic plug which plugs intothe main circuit board.
      (E) Identify the cathode end of the diode (the banded end). Twist cathode
end of the diode to the 10 ohm resistor. Cut of the extra wire so that 1/2" of
twisted wire remains. Cut the other ends of the diode and resistor to 1/4".
      (F) Bend the diode/resistor into a jackknife configuration.
      (G) Plug the resistor end into the orange wirw of the AC adapter block on
the main circuit board. Plug the diode into the red wire side of the block.
(The resistor and diode wires should fit snugly against the pins in the
connector block.)
      (H) Double check to make sure that the cathode of the diode is oriented
away from the red wire at the block, and is twisted to the resistor whose end
is to the orange wire of the block.
.
OPERATION:
	Each time you use the AC adapter, the NiCads will receive a charge. 
The NiCads will charge up completely over night and should provide enough power
for the entire day.  I have been using my 100 for over a week this way and it
works great!  No more batteries to change.  (and the message was then signed by
Dr. Preble).
	  Don Corbitt has used the conversion for a year and a half and reports
complete success. 
	 Hugh Tinling 75755,1540