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                                                                    EXHIBIT 10.8

                             STOCK OPTION AGREEMENT

       S.T. Research Corporation (hereinafter "Corporation"), desiring to afford
an opportunity to the Director named below to purchase certain shares of the
Corporation's common stock, hereby grants to the Director, and the Director
hereby accepts, the following option to purchase shares. Any such purchase shall
be made during the term ending on the expiration date of this Option and shall
be subject to the terms and conditions that follow:

1.     IDENTIFYING PROVISIONS

       As used in this Option Agreement, the following terms shall have the
following respective meanings:

              A.     Director:                            Chuck Bernard
                                                          ----------------------
              B.     Date of Grant:                       January 31, 1992
                                                          ----------------------
              C.     Number of Shares Optioned:           10,000
                                                          ----------------------
              D.     Option Exercise Price Per Share:     2.50
                                                          ----------------------
              E.     Expiration Date:                     January 31, 1996
                                                          ----------------------

2.     TIMING OF PURCHASES

       This Option is exercisable in full at any time during the period between
the Date of Grant and the Expiration Date.

3.     RESTRICTIONS ON EXERCISE

       The following provisions shall apply to the exercise of this Option:

       A.            Termination of Directorship. If the Director ceases to be
              employed as a director of the Corporation for any reason other
              than death, only that portion of this Option exercisable at the
              time of such termination may thereafter be exercised, and it may
              not be exercised more than thirty (30) days after such termination
              nor after the expiration date of this Option, whichever date is
              sooner,


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              unless such termination is by reason of the director's permanent
              and total disability, in which case such period of thirty (30)
              days shall be extended to one (1) year.

       B.     Death of Director. Should the Director die during the term of this
              Option, the Director's legal representative(s) or the person(s)
              entitled to act as such under the Director's last will and
              testament or under applicable interstate laws, shall have the
              right to exercise this Option, but only for the number of shares
              for which the Director was entitled to exercise on the date of his
              death in accordance with Section 2 of this Agreement, and such
              right shall expire and this Option shall terminate thirty (30)
              days following the date of the Director's death or on the
              expiration date of this Option, whichever date is sooner. In all
              other respects, this Option shall terminate upon such death.

3.     NON-TRANSFERABLE

       The Director may not transfer this Option except by will or the laws of
descent and distribution. This Option shall not be otherwise transferred,
assigned, pledged, hypothecated or disposed of in any way, whether by operation
of law or otherwise, and shall be exercisable during the Director's lifetime
only by the Director or his guardian or legal representative.

5.     ADJUSTMENTS AND CORPORATE REORGANIZATIONS

       If the outstanding shares of the company subject to this Option are
increased or decreased, or are changed into or exchanged for a different number
or kind of shares or securities, as a result of one or more reorganizations,
recapitalizations, stock splits, reverse stock splits, stock dividends or the
like, appropriate adjustments shall be made in the number and/or kind of shares
or securities for which the unexercised portions of this Option may thereafter
be exercised, all without any change in the aggregate exercise price applicable
to the unexercised portions of this Option, but with a corresponding adjustment
in the exercise price per share or other unit. No fractional share of stock
shall be issued under this Option or in connection with


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any such adjustment. Such adjustments shall be made by or under authority of the
Corporation's Board of Directors whose determinations as to what adjustments
shall be made, and the extent thereof, shall be final, binding and conclusive.

       Upon the dissolution or liquidation of the Corporation, or upon a
reorganization, merger or consolidation of the Corporation as a result of which
the outstanding securities of the class subject to this Option are changed into
or exchanged for cash or property or securities not of the Corporation's issue,
or upon a sale of substantially all the property of the Corporation to, or the
acquisition of stock representing more than eighty percent (80%) of the voting
power of the stock of the Corporation outstanding by, another corporation or
person, this Option shall terminate, unless provision be made in writing in
connection with such transaction for the assumption of options theretofore
granted under the Stock Option Plan under which this Option was granted, or the
substitution for such options of any options covering the stock of a successor
employer corporation, or a parent or subsidiary thereof, with appropriate
adjustments as to the number and kind of shares and prices, in which event this
Option shall continue in the manner and under the terms so provided. If this
Option shall terminate pursuant to the foregoing sentence, the Director shall
have the right, at such time prior to the consummation of the transaction
causing such termination as the Corporation shall designate, to exercise the
unexercised portions of this Option, including the portions thereof which would,
but for this Section entitled "Adjustments and Corporate Reorganizations," not
yet be exercisable.

6.     EXERCISE: PAYMENT FOR AND DELIVERY OF STOCK

       This Option may be exercised by the Director or other person entitled to
exercise it by giving four (4) business days' written notice of exercise to the
Corporation specifying the number of shares to be purchased and the total
purchase price, accompanied by a check to the order of the Corporation in
payment of such price. If the Corporation is required to withhold on account of
any present or future tax imposed as a result of such exercise, the notice of
exercise shall be accompanied by a check to the order of the Corporation in
payment of the amount of such


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withholding.

7.     RIGHTS IN SHARES BEFORE ISSUANCE AND DELIVERY

       No person shall be entitled to the privileges of stock ownership in
respect of any shares issuable upon exercise of this Option, unless and until
such shares have been issued to such person as fully paid shares.

8.     REQUIREMENTS OF LAW AND OF STOCK EXCHANGES

       By accepting this Option, the Director represents and agrees for himself
and his transferees by will or the laws of descent and distribution that, unless
a registration statement under the Securities Act of 1933 is in effect as to
shares purchased upon any exercise of this Option.

       A.     any and all shares so purchased shall be acquired for his personal
              account and not with a view to or for sale in connection with any
              distribution, and

       B.     each notice of the exercise of any portion of this Option shall be
              accompanied by a representation and warranty in writing, signed by
              the person entitled to exercise the same, that the shares are
              being so acquired in good faith for his personal account and not
              with a view to or for sale in connection with any distribution.

       No certificate or certificates for shares of stock purchased upon
exercise of this Option shall be issued and delivered prior to the admission of
such shares to listing on notice of issuance on any stock exchange on which
shares of that class are then listed, nor unless and until, in the opinion of
counsel for the Corporation, such securities may be issued and delivered without
causing the Corporation to be in violation or incur any liability under any
federal, state or other securities law, any requirement of any securities
exchange listing agreement to which the Corporation may be a party, or any other
requirement of law or of any regulatory body having jurisdiction over the
Corporation.


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9.     NOTICES

       Any notice to be given to the Corporation shall be addressed to the
Corporation in care of its Secretary at its principal office, and any notice to
be given to the Director shall be addressed to him at the address given beneath
his signature hereto or at such other address as the Director may hereafter
designate in writing to the company.

       Any such notice shall be deemed duly given when enclosed in a properly
sealed envelope or wrapper addressed as aforesaid, registered or certified, and
deposited, postage and registry or certification fee prepaid, in a post office
or branch post office regularly maintained by the United States Postal Service.

10.    LAWS APPLICABLE TO CONSTRUCTION

       This Agreement has been executed and delivered by the Corporation in the
Commonwealth of Virginia, and this Agreement shall be construed and enforced in
accordance with the laws of said State.

       IN WITNESS WHEREOF, the Corporation has granted this Option on the Date
of Grant specified above.

                                        S.T. RESEARCH CORPORATION

WITNESS:                                By:    /s/ S. R. Perrino
                                               -----------------------------

/s/ Yvonne L. Wilson                    Name:  /s/ S. R. Perrino
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                                        Title: President
                                               -----------------------------

                                        ACCEPTED:

                                        By:    /s/ Charles W. Bernard
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                                        Name:  /s/ Charles W. Bernard
                                               ----------------------

                                        Title: Director
                                               --------