===== Replacement drive belt for Tandy Disk Drives =====

Source is Russell Industries
Part numuber is FRW8.5 which is a Flat Rubber Belt that has the dimensions:
  Inside Circumference (IC) of 8.5 inch
  Cross Section (C/S) of .150 inch
  Wall (WALL) of .023 inch.
See [ http://www.russellind.com/client/download/belts.pdf ]
Club 100, as of June 2007, is selling these belts for $5.00 plus postage.  Ordered/received two belts.

Replaced original flat belt, after aging and stretching, has Inside Circumference (IC) of 9-5/16" x 1/8" (03/15/05).
Replaced original flat belt, after aging and stretching, has Inside Circumference (IC) of 9-3/8" x 1/8" (07/05/07).

Tools needed to change TDD belt:
    Phillips screwdriver with a shank diameter no more than 1/4" thick.
    Phillips screwdriver with a shank diameter of between 1/16" thick and 3/32" thick.
    Any kind of soft tool to snare belt, see step 25.

Procedure to change TDD belt:
1.  Remove RS-232C cable from connector at rear of disk drive.
2.  Eject and remove any diskette or cardboard head vibration protector, and close diskette door.
3.  Place disk drive top-side-down.
4.  Remove plastic battery door cover.
5.  Remove batteries.
6.  Remove 2 machine screws at rear of bottom case-half.  Shake them loose to get them out of the 
    recessed holes of bottom case-half.  These screws are 5/8" long.
7.  Place disk drive top-side-up.
8.  Grasp top case-half at its rear end, while pulling backward rotate it upward 30 degree -- front end of 
    case-half releases from front escutcheon and slides away.

THIS STEP DOES NOT APPLY TO TDD2.
??. See the aluminum shield which is retained by two plastic ferrules and moves freely under the plastic
    ferrules.  Remove 2 small self-tap screws and their plastic ferrules which retain the aluminum shield.
    These screws are 5/16" long.

9.  Place disk drive top-side-down.  Completely loosen 2 machine screws at holes in the bottom edge of the
    escutcheon.  Hold escutcheon seated to disk drive and shake the 2 machine screws loose to get them out
    of the holes of escutcheon.  These screws are 5/8" long.
10. Use one hand to grasp and hold disk drive by its bottom case-half.  Use other hand to hold escutcheon.
11. Rotate disk drive so that escutcheon faces down -- disk drive is in a vertical attitude.
12. While holding disk drive, remove escutcheon by lowering it.  Escutcheon has two loose plastic parts:
    eject plunger, and power slide.  Do not disturb or remove the loose plastic parts.  Set escutcheon and
    its loose plastic parts aside.
13. Place disk drive top-side-up with its front facing toward you.  Remove 2 very small self-tap screws
    which fasten a small circuit board to the left side of bottom case-half.  These screws are 7/32" long.
    The circuit board mounts the power slide-switch and a rectangular LED (LOW BATTERY). Do not disturb the
    position of the rectangular LED on the small circuit board during this step.

15. Place disk drive top-side-down with its front facing toward you.  Completely loosen 2 machine screws at
    front of bottom case-half.
16. Gently lift and rotate bottom case-half to your right, so that it swings out of the way to give you
    free access to the large circuit board.  Shake the 2 machine screws loose to get them out the recessed
    holes of bottom case-half.  These screws are 5/8" long.
17. See the large circuit board, and a long vertical circuit board (has a shield) which now is free to move
    somewhat.  Below the front edge of the large circuit board, see the (9-pin) connector which holds a
    thin plastic flexible flat cable -- do not disturb this flat cable.
18. Below the left edge of the large circuit board, see two plastic cable connectors: a 4-pin near the
    front, and a 2-pin near the rear.  Unplug both of these plastic cable connectors.

ONLY 3 SCREW HEADS ARE EXPOSED ABOVE A THIN FLEXIBLE SHEILD PLATE; 4TH SCREW HEAD IS UNDERNEATH THE SHEILD PLATE.
19. Remove 4 machine screws that fasten the large circuit board to metal mounting posts of the chassis.
    These screws are 1/8" long.
SET ASIDE SHIELD PLATE, AND NOTE THAT ITS UPPER SURFACE IS METALIZED BUT ITS LOWER SURFACE IS NOT METALIZED
AND IS NOT CONDUCTIVE.

NO 11-PIN CIRCUIT PACK IS FOUND ON TDD2.
20. Grasp the large circuit board by its left edge.  Pull this edge upward about an inch or less.  The body
    of an 11-pin circuit pack comes free from a rectangular hole in the chassis.  Let the this 11-pin
    circuit pack rest against the chassis surface, beside the rectangular hole.  The left-rear corner of
    the large circuit board now is raised slightly.  This gives you some access to the chassis and mechanics
    that are underneath the large circuit board.
21. Grasp the large circuit board by its left-rear corner.  Lift this corner up an additional inch.  This
    gives you additional access to the mechanics underneath.
22. Look under the large circuit board.  Identify the flat belt that ciruits (or did at one time went)
    around the flywheel at the front and the capstan at the rear.  Replacing this flat belt is your goal.

==================
NO 20-PIN CIRCUIT PACK IS FOUND ON TDD2.
23. This step is optional.  You may grasp the the large circuit board by its right edge and raise it enough
    (the body of a 20-pin circuit pack comes free from a rectangular hold in the chassis) so you can rotate
    it completely out of the way and obtain complete access to the mechanics underneath.
==================

24. Remove the old flat belt.

24.5 Inspect the capstan surface.  If any belt residue is on the capstan surface, clean the capstan.

25. Install the new flat belt.  It circuits around the flywheel and the capstan.  Start by looping the belt
    over the flywheel at the front of the disk drive.  Dress the loose portion of the belt so it lays toward
    the rear of the disk drive.  Use a soft tool to snare the loose end of the belt.  Loop the snared end of
    the belt over the capstan -- the belt stretches slightly.  Unsnare the belt once it on the capstan.  Use
    your finger to rotate the capstan several times and watch the belt turn the flywheel.  Be sure the belt
    has no twists.

====????====
26. Reverse all disassembly steps to reassemble the disk drive.  These steps are step 27 through 50.
====????====

27. Lower the left-rear corner of the large circuit board so its 11-pin circuit pack rests against the
    chassis surface, beside the rectangular hole.  Inspect the thin plastic flexible flat cable below the
    front edge of the large circuit board to see if you disturbed it.  It should still be held in its
    (9-pin) connector -- if not, correct it now.
28. Grasp the large circuit board by its left edge.  Move its position slightly, as needed, to align the
    11-pin circuit pack over the rectangular hold in the chassis.  Then lower the large circuit board so it
    seats onto its four metal mounting posts of the chassis.

OBTAIN THE SHIELD PLATE AND THE 4 MACHINE SCREWS THAT ARE 1/8" LONG.

29. Obtain the 4 machine screws that are 1/8" long, and thread them into the metal mounting posts.  This
    fastens the large circuit board in place.  The screw that is rearmost to the disk drive provides an
    electrical frame connection with the chassis -- make that screw very tight.  Make the other three screws
    moderately tight.
30. Plug in the two plastic cable connectors that were unplugged at step 18.  Be sure they seat firmly.
31. Position the long vertical circuit board (has a shield) next to the large circuit board.  Rotate the
    bottom case-half into position gently and seat it on the chassis -- some slight positioning of the long
    vertical circuit board (has a shield) may be needed for the bottom case-half to seat.
32. Obtain 2 machine screws that are 5/8" long, insert them through the recessed holes at front of bottom
    case-half.  Thread them into the chassis.  Make these screws slightly tight -- do not over tighten them
    because the plastic of the bottom case-half (at recessed holes) can crack.
33. Place disk drive top-side-up with its front facing you.

THIS STEP DOES NOT APPLY TO TDD2.
34. Obtain the 2 small self-tap screws that are 5/16" long and their plastic ferrules.  Separate the screws
    from their plastic ferrules.  Insert the ferrules into holes of the aluminum shield.  Look through the
    holes of the ferrules and see how well the holes of the circuit board (under the aluminum shield) align
    with holes in screw posts of bottom case-half.  Grasp the long vertical circuit board in the area of its
    fuse and move it as needed to align these holes.  Insert the 2 small self-tap screws into their plastic
    ferrules and thread them into screw posts of bottom case-half.  Make these screws slightly tight -- do
    not over tighten them because the plastic of the bottom case-half can crack.  Note that the aluminum
    shield moves freely under the plastic ferrules that retain it.

35. Do not disturb the position of the rectangular LED on the small circuit board during this step.  Obtain
    the 2 very small self-tap screws, and use them to fasten the small circuit board to the left side of
    bottom case-half.  Make these screws slightly tight -- do not over tighten them because the plastic of
    the bottom case-half can crack.
36. Obtain the escutcheon and its loose plastic parts: eject plunger, and power slide.  If any of these
    loose parts have become separated from the escutcheon, assemble the loose parts as follows.  Place the
    escutcheon face-down with its bottom edge facing toward you.  The two loose plastic parts can be
    oriented in the escutcheon correctly or incorrectly.  Orient the eject plunger so that its angled face
    is closest to the bottom edge of the escutcheon.  Orient the power slide so that its red color band is
    closest to the bottom edge of the escutcheon.  Slide the power slide toward the bottom edge of the
    escutcheon until it stops at its power off position (red color band is not visible if viewed from front
    of escutcheon).
37. Use one hand to grasp and hold disk drive by its bottom case-half.  Use other hand to hold escutcheon,
    and keep it face down and level so that its loose parts do not move.
38. Rotate disk drive so that its diskette door faces down -- disk drive is in a vertical attitude.
39. While holding disk drive, gently raise the escutcheon to it.  Watch the rectangular LED (LOW BATTERY) as
    you raise the escutcheon to be sure this LED aligns with its rectangular hole in the escutcheon.  The
    escutcheon is fully seated when its bottom edge has no gap with the lip of the bottom case-half.
40. Obtain 2 machine screws which are are 5/8" long.
41. While holding escutcheon fully seated, rotate disk drive so it is top-side-down.  Insert the 2 machine
    screws through holes in the bottom edge of the escutcheon.  Thread the 2 machine screws into the
    chassis.  Make these screws tight.
42. Place disk drive top-side-up.
43. Grasp top case-half by its rear end.  Rotate it 30 degree so its front end is lower than its rear end.
    Keep it at 30 degree attitude and set both front lips (left side and right side) of the case-half under
    the top lip of the escutcheon.  While pushing forward rotate the case-half so its rear end lowers and
    seats onto the lower case-half.
44. Place disk drive top-side-down.
45. Obtain 2 machine screws that are 5/8" long, insert them through the recessed holes at rear of bottom
    case-half.  Thread them into the (metal inserts of) screw posts of top case-half.  Make these screws
    slightly tight -- do not over tighten them because the plastic of either case-half can crack.
46. Install batteries.
47. Install plastic battery door cover.
48. Place disk drive top-side-up.
49. Press eject plunger to open diskette door, insert a diskette or cardboard head vibration protector, and
    close diskette door.
50. Insert RS-232C cable into connector at rear of disk drive.  This procedure is finished.