Memory Expansion Board  (250-1009)  Installation        Faxback Doc. # 2009

1. WARNING: Turn off all equipment. If any unit is on, you can damage the
   CPU or the option board. Wait at least 10 seconds before removing or
   inserting any board into the computer.

2. To avoid static electricity build-up, which can destroy certain integrated
   circuits, touch a grounded metal object before handling any circuit board.

   Note: DO NOT stand on a carpeted floor while performing this work.

3. Remove the 2 screws on the front of the main unit. Remove the cover by
   sliding it away from the rear of the unit, parallel to the computer.

4. Rotate the chassis so that the fan faces you. To the immediate right of
   the fan are 3 option slot covers, each fastened to the rear of the chassis
   by a sheet-metal screw. On the main printed circuit board directly behind
   these covers, are 3 thin, black edge connectors. Select any empty socket
   as the location for the board. It makes no difference which you use. How-
   ever, if you plan to install a hard disk controller board at some later
   data, you should insert the first memory board in the extreme right-hand
   connector as you face the rear of the machine. this will eliminate the
   need to remove and re-insert the memory board at that time.

5. Remove the sheet metal screw from the top of the selected cover. Tilt the
   metal strip away from you and lift the strip so that the tab on the panel
   clears the bottom of the slot. Store the cover in a safe place for pos-
   sible future replacement.

6. Discharge any static build-up by touching a grounded metal object. Now
   grasp the board by its upper edges and position it above the black
   edge-connector socket. Insert the option card panel into the slot on the
   rear of the chassis, in the same way the option slot covers are mounted.
   At the same time, apply even downward pressure engaging the edge-connector
   into its socket. Align the entire card so that the U-shaped cutout on the
   top of the option card panel is positioned over the screw-hole on the rear
   of the chassis. Replace the screw you removed before and tighten it to
   secure the board. Do not overtighten the screw.
7. Replace the top cover.

Check Out:

1. With the board in place and the cover installed, power up the machine and
   the monitor. You need not have a disk in your drive.

2. The first message that will appear on your screen will designate your
   available memory. For example, if you installed you first Memory Expansion
   Board with 128K, that RAM combined with the built-in RAM would give you
   256K total.

The message when you power up will read:
    MEMORY SIZE = 256K

Note:

If you see any other message, such as MEMORY FAULT ERROR, turn the unit
off and wait at least 10 seconds before re-opening the machine. Then, open
the cover and be certain that the memory board has been properly seated. If
after making this check, re-closing the unit and powering up once more you
should get the same error message, contact your Radio Shack store for addi-
tional assistance.

Use in the TANDY 1200:
The 512K Memory Expansion Board, 250-1009 may also be used in the Tandy 1200.

Before proceeding with installation of the board, make the jumper
configuration shown for the board. Then, after opening the Tandy 1200,
adjust the DIP switch options on the Main Logic Board. For instruction on
this process refer to the CPU's User's manual.

(CSS/jlc-03/27/94)