ORIGINALLY PUBLISHED IN LIMA NEWSLETTER JANUARY 1987
 
 
 
CHARLIE SAYS:
 
                   CONSOLE CLEANING:
           A SOLUTION TO MANY CONSOLE PROBLEMS 
 
    Do modules (particularly EXTENDED BASIC) refuse to
work when inserted into your console? Does your
EXTENDED BASIC frequently crash while in use? Do some
of the keybard keys fail to respond every now and then?
All of these problems are usually caused by dirty
connections within the console, not by bad modules.
Taking the console apart and cleaning the places where
things plug together will do away with all of the above
problems.  I know from first hand experience. 
 
Cleaning the inside connections of the console is a job
any idiot can do successfully.  There are three major
components inside, the power supply, the main circuit
board, and the keyboard.  These all easily unplug from
one another once the screws holding them to the plastic
console enclosure are removed.  The only tools needed
to clean the inside of the console are a phillips
screwdriver, some isopropyl (rubbing) alcohol, a few
cotton swabs, and a cereal box.  No soldering is
required.   
 
--  Turn the console upside down and remove the 7
screws.  Gently separate the bottom from the rest of
the console.  With a little wiggle, the on/off switch
will fall out.  
--  Revove the two corner screws that hold the power
suppply in place.  This is the green circuit board.
Gently remove the power supply and unplug it from the
main circuit board (the one with the metal covering). 
With some alcohol and a swab scrub the exposed pins of
this plug that are on the green circuit board. 
--  Remove the three screws (two corner and one
recessed inside a hole in the metal cover) holding the
main circuit board in place.  Unless you have a good
reason to, leave the metal cover (the heat sink)
attached.   
--  Revove the 4 screws that hold the keyboard to the
console housing.  Lift the main circuit board and the
keboard from the computer.  Then unplug the keyboard
from the main circuit board.  Use a swab and alcohol to
scrub (yes, really work at scrubbing them) the pins to
this plug on the main circuit board.  This cleaning
should solve any irregular keyboard problems you may
have had. 
-- Remove the "L" shaped grom extender from the main
circuit board.  This is the thing that modules plug
into.  It may now be in the console housing instead of
th circuit board.  Cut a piece of a cerial box so it is
just wide enough to fit into the connector in the main
circuit board where the "L" shaped grom extender was.
Dip this cardboard in some alcohol. Insert it into the
grom extender plug in the main circuit board and move
it in and out as well as sideways to clean this
connector. 
--  Using your fingers lift up both ends of the plastic
end of the "L" shaped grom extender.  This plastic
piece is located where modules plug into the computer
an has a felt pad inside.  Throw the plastic piece
and its felt pad away, or revove the felt pad and
replace the plastic without the pad.  This pad coats
modles with accumulated dirt each time a module is
inserted into the computer.  Use alcohol and a swab to
scrub (really scrub hard) both sides of the flat
connectrs on the grom extender that plug into the main
circuit board.  Then use cardboard soaked in alcohol to
throughly scrub the place where modules are inserted. 
--  Reassemble the console.  Connect the keyboard to
the main circuit board and lay these in the upside down
top of the console.  Screw in the keyboard and then the
main circuit board.  Connect the power supply, lay it
in position and screw it in.  Route the power input
jack to its proper position in the back of the console
and then screw on the bottom of the console.  Finally
push in the loose external on/off switch.  It should
pop right in. 
 
    The entire procedure outlined above takes about
15-20 minutes, less if you are more experienced. You
may be amazed at the improvement in performance.  Your
EXTENDED BASIC should now load first time every time. 
 
    This may be a good time to consider replacing the
black & silver console power supply with a "switching
power supply".  These switching supplies run MUCH
cooler than the original since they only deliver power
output when it is required.  At other times they do not
deliver unwanted heat producing power.  Switching power
supplies were used by TI in the later model grey
consoles and work fine as exact replacements in silver
consoles.  Some RADIO SHACK stores have them in stock
(part #277-1016) for $4.95 and they are also advertised
in the Computer Shopper for about the same price.
 
    The Lima User Group will have a demonstration of
console disassembly and cleaning in our February 87
meetng.  Be there!!