300 BPS Internal Modem  (250-1003)    Installation     Faxback Doc. # 4485

It is recommended that the internal modem board be installed by technicians
at a Radio Shack Service Center.

1. Turn off all equipment. If the computer is on during installation, you 
   can damage the central processing unit or the option board.

2. To avoid static electricity buildup, which can destroy certain integrated
   circuits, touch a grounded metal object before handling any circuit board.
   Do not stand on a carpeted floor while performing this work.

3. Remove the two 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 three option slot covers, each fastened to the rear of the 
   chassis by a sheet-metal screw. On the main logic board directly behind 
   these covers are three thin, black edge connectors. Select any empty 
   socket as the location for the modem board. It makes no difference which 
   one you use.

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 
   possible future replacement.

6. Discharge any static buildup by touching a grounded metal object. Now 
   grasp the modem board by its upper edges and position it above the 
   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-con-
   nector 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 earlier and tighten
   it to secure the board. Do not over tighten the screw.

7. Replace the top cover.

CONNECTING THE TELEPHONE TO THE MODEM

The way to connect the modem board depends on how the telephone is connected
to the wall.

If the telephone has the older style, four-prong connection, use the adapter
Catalog Number (279-360) to connect it to the modem.

If the telephone is wired directly to the wall, contact the telephone com-
pany.

(abo-07/28/93)