SERVICE REPAIR PROCEDURE

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                                                      8/25/83 CS

                SERVICE REPAIR PROCEDURE

PURPOSE: Field service quality update of TOPO I

MATERIALS REQUIRED:
Description                          Quantity/unit

Heat sink compound
Loctite 242 or 262

Mica washers                                  1
3amp slow blow fuse                           2
Lugs   size A .250                            4
       size B .188                            4
Split lock washer  #8                         2
                   #10                        6
Spring loaded relay clip                      1
Plastic tubing for LED leads

EQUIPMENT REQUIRED:

Phillips screw driver

Nail or similar object to remove rivets
Set of nut drivers
Lug crimpers: two sizes
Wire strippers 20 gauge
Pliers
DVM

Torque driver set at 231bs.
Apple II (IIe or IIplus) with drive
Monitor

TOPO transmitter
Apple II joystick
Topo basic

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SERVICE PROCEDURE:

I. BODY/BELLY PAN DISASSEMBLY

Remove all rivits from the belly pan (connecting the body to
the base, 8 rivits in new rev. 4 rivits in old rev.) and using a
nail or other similar object, push the center of the plastic
rivit into the body and pull out the outer part of the rivit.
Mark the belly pan to insure which is the front and rear (this
will help when TOPO is put back together). Then remove the four
screws from the legs (near the bottom of the body above the foot
lights). Lift

the body up by grabbing on the legs above the foot lights on both
sides, gently pull up and out until the body comes apart from the
base. Reach into the backside of the body and disconnect all the
cables connected to the battery monitor board. Also, disconnect
both foot light cables. Continue to lift the body straight up and
over the antenna (be careful not to poke your eye). Be sure to
match up the right body with the right belly pan if more than one
TOPO is being reworked. Remove the battery monitor board from the
body by unscrewing the nuts on the outside of the body on the
power jack and the two switches. The switch buttons must be
removed first to get at the nut. To remove, carefully pull the
board forward from the inside. Be careful with the LED's.

II. BATTERY MONITOR BOARD

Inspect the power jack. Look inside the jack for any passible
shorts. You would be able to see a lead on the inside of the jack
touching the center post if the jack was shorted. Resolder the
power jack on the battery monitor board by applying jumper wires
1/3" on the top side of the board at each jack lead parallel on
top of each trace. On the backside of the board apply additional
solder to each lead for good board contact. Inspect the yellow
and tri-color LED to be sure that the leads have the plastic
tubing. If not, unsolder the leads and place the tubing on the
leads, enough to cover the lead from the light to the board.
Resolder the LED back onto the board. Next, inspect the relay
clip. Be sure the clip is spring loaded. To check this - lightly
move the relay to one side so that the leads on one side are
partway out. If the wrong clip is on, the relay will remain
there. If the correct relay clip is on, the relay will spring
back into place. To remove the clip - pull out on the sides of
the clip and pull out and off. To replace the clip, secure the
ends into the holes on the relay socket and lift over the relay.
Be sure the relay is secure and in place.

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III. POWER TRANSISTOR

Taking the base, set it upside down on some foam (so as not
to damage the contoller board) remove the belly pan by unscrewing
the 8 screws on the bottom and lift up. Set the belly pan aside
and the base right side up. Locate the power transistor TIP125
which is connected to the side of the base and remove. Observe
the transistor for any cracks or melting substances, if any of
these are present replace the transistor.  Remount using a new
piece of mica washer. Apply heat sinking compound to both sides
of the mica washer and loctite to the threads of the screw and
remount, keeping the plastic washer between the screw head and
the transistor heat sink. Tighten the screw and nut.

IV. CONTROLLER BOARD (FUSES)

Locate the two fuses on the controller board and remove any
that are 3amp fast blow (determined by a straight line through
the fuse). Replace with 3amp slow blow.

V. BATTERIES  (battery and motor lugs)

Remove the battery brackets and disconnect the 4 battery
lugs, then set the batteries aside. Take hold of the connectors
and cut the existing lugs off near the end of the lug. Strip the
wires a quarter of an inch using a 20 gauge wire stripper.
Replace the lugs with the larger size (A .250) lugs and recrimp
them onto the wires. Replace the batteries and push the lugs back
onto the battery leads. Be sure to connect the red wires to the
red battery leads and the black wires to the black battery leads.
Gently pull on the wires to insure good crimping and a good
battery connection. Put the batteries in place keeping the foam
on either side of the batteries and replace the battery brackets.

Locate the two motors and remove the wires connected on the
top of the motor. Using the same instructions from the above
paragraph, remove the lugs and strip the wire. Replace the lugs
with the smaller size lugs (B .188) and recrimp. Replace the
wires back onto the motor with the red wires facing each other
and the black wires facing out.

Take the other end of the two battery wires and using a DVM
measure the voltage of each battery. Set the DVM to read 200volts
DC. insert the red DVM lead into the red battery lead and the
black DVM lead into the black battery lead. Each battery should
read no less than 11.1 volts, if a battery should read less than
11.1 volts it must be replaced with a new battery.

VI. WHEELS

Reposition the base on its back on top of the foam and remove
the three outer screws on both aluminum wheel hubs. Next remove
the start washers and replace with #10 split lock washer, then
tighten the screws with a torque driver set at 231bs. Remove the
center screws and add a #8 split lock washer between the screw

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head and the flat washer. Add loctite 242 or 262 to the threads
of the screws and tighten the screw down with a 231b. torque
driver.

Vll. REASSEMBLY - FINAL CHECK

Give the controller board and battery monitor board one close
look before putting it back together. Keep an eye out for any
missing, loose, or damaged parts. Look also at the footlight
board and the other 4 LED's to insure proper mounting and
existence (be sure lights are still mounted). The head switch
cable should still be tie wrapped near the battery monitor board
mount, on the body (with no strain on the cable). Before
remounting the belly pan look at the two coasters for any cracks
or rust (replace as needed). Keeping the base on its backside on
the foam, mount the belly pan and reassemble it to the base. Next
place the battery monitor board onto the body and remount using
the same nuts on the power jack and switches(DO NOT OVER TIGHTEN
THE POWER JACK). Put the correct switch button on the right
switch. The green switch should be next to the amber LED and the
red switch next to the white LED. Set the body over the antenna
making sure the antenna goes through the neck hole for maximum
transmitting distance. Match up the front of the belly pan to the
front of the body. When the body gets close enough to the base,
reconnect all connectors (head switch, batteries and main cable
from the battery monitor board to the main CPU, and all LED's)
into their proper connector. Set the body gently over the base
holding onto the legs. Make sure that the base flaps go outside
the body flaps and the front and rear body flaps overlap the base
flaps. Line up the 4 screw holes and insert. Next, line up the
rivet holes, insert the rivets, and using a hard blunt object
push all the rivet posts into the body doing the ones on the
front and rear of the body then going to the ones on the sides.
Check the decals on the body and remove any smudges with a damp
cloth. This completes the rework mode.

Vlll. FUNCTIONAL TEST
With TOPO back together do a short functional test to

determine correct operation. Turn on the TOPO transmitter and
boot up TOPO BASIC on the Apple 11 and type in "gosub 6000"
return and "gosub 5000" return. Now TOPO can be run using the
Apple 11 joystick. Have TOPO run forwards and backwards abserving
the footlight operation. All green lights should come on in the
forward position and all red lights should come on in the reverse
position. When TOPO is going forwards or backwards, look to make
sure TOPO is not turning in any direction. This can determine if
the motors are running at the same speed. Be sure TOPO can
function in all directions of turning. Also, plug in the charger
to insure that TOPO can take a charge with the Tri-color LED
turning green and that the charger does work.