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AST RESEARCH, INC.           TECHNICAL BULLETIN # 1011                11-10-94

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             ASCENTIA 900N TRACK STICK DRIFTING WITH CELLULAR PHONE


PROBLEM:        When using a cellular phone near an AST Ascentia 900N
                notebook, under Windows version 3.1, the J-stick cursor or
                mouse pointer begins to drift toward the edge of the screen

CAUSE:          The Ascentia 900N's lower board acts as an antenna; it receives
                the cellular phone output signals and feeds them into the
                mouse control circuitry, causing the circuit to interpret that
                the track stick is being pushed, thus moving the mouse cursor.

SYSTEMS
AFFECTED:           AST                                               REVISION
                PART NUMBER          DESCRIPTION                        LEVEL

                501299-2XX      ASCENTIA 900N 4/50 CS10                  All
                501300-3XX      ASCENTIA 900N 4/50 CT9                   All
                501302-2XX      ASCENTIA 900N 4/75 CS10                  All
                501304-3XX      ASCENTIA 900N 4/75 CT10                  All

SOLUTION:       The mouse cursor movement does not cause a problem in the
                Ascentia 900N system.  The track stick still operates
                normally, even when it is close to a source of RF interference
                such as a cellular phone, cordless phone, or radio transceiver.
                Operate these devices at a distance of at least two feet from
                the Ascentia 900N to avoid the track stick drifting.