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                                                                    EXHIBIT 10.5

                       [SKYSTREAM CORPORATION LETTERHEAD]


June 12, 1997



Mr. James D. Olson
9 Ashdown Place
Half Moon Bay, CA 94019

Dear Jim:

On behalf of the Board of Directors of SkyStream Corp. (the "Company"), I am
pleased to offer you the position of President, Chief Executive Officer and
Member of the Board of Directors, commencing on or before July 10, 1997. Your
base salary will be $14,583.33 per month ($175,000.00 on an annualized basis),
which will be paid in accordance with the Company's normal payroll procedures.
You will also receive an annual bonus based on meeting objectives defined by
you and agreed upon by the Company's Board of Directors. Your targeted bonus
for meeting these objectives will be $100,000.00. We expect that your
objectives will include, but will not be limited to, revenue and profit
targets. Your base salary and bonus will be reviewed annually by the Board of
Directors or compensation committee. As an employee of the Company you will be
eligible to participate in benefits generally provided by the Company to its
employees.

At its next meeting, the Company's Board of Directors will grant you the right
to purchase 1,092,500 shares of Common Stock at the fair market value ($0.10
per share) for such shares pursuant to the Company's Stock Option Plan,
including the standard vesting provision thereunder. At your option, you may
select to exercise your stock options subject to a company Repurchase Right
(the "Repurchase Right"), that would lapse on the same schedule that the stock
options would normally vest. If you elect to exercise your options subject to
the Repurchase Right the purchase price of the Common Stock may be financed
with a full recourse promissory note (the "Note") payable to the Company. The
Note shall bear interest at the minimum rate allowable to avoid imputation of
interest (currently 6.8 percent) compounded annually. Interest shall be
forgiven annually as long as you remain employed by the Company, with the
amount of such forgiveness grossed up for federal and state income tax
purposes. The Note shall be due and payable upon the earlier of (i) five years
from the date of the Note, or (ii) 90 days after the termination of your
employment with the Company. In addition, the proceeds from any sale by you of
any shares of Common Stock of the Company shall be applied to repay the Note.
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MR. JAMES D. OLSON                                                 JUNE 12, 1997


Your employment with the Company is "at will" and may be terminated by you or by
the Company at any time, with or without cause (as defined below). If, however,
the Company decides to terminate your employment for reasons other than cause,
the Company shall pay you all compensation (including base salary and bonus) due
to you at the date of termination and continue to pay you in equal installments,
an amount equal to the sum of your then current base salary for a period of six
(6) months from the date of termination. During such period, you shall continue
to vest your stock options and be entitled to participate in the Company's
employee health, medical, and other benefits on the same basis as if you were an
employee. If in the first year of your employment, the Company is acquired or
sold, and, as a result of such acquisition you are involuntarily or
constructively terminated without cause, you will nonetheless vest an aggregate
of 25 percent of your stock options, or, in the case of a Repurchase Right, an
aggregate of 25 percent of the Company's Repurchase Right will lapse.

In the event your employment is terminated for cause, you will be entitled to
any unpaid salary and bonus (if any) due to you pursuant to this agreement
through the date of termination and you will be entitled to no other
compensation from the Company. "Cause" shall mean (i) willful and repeated
failure to comply with the lawful written directions of the Company's Board of
Directors, (ii) gross negligence or willful misconduct in the performance of
duties for the Company, (iii) commission of any act of fraud, or (iv) conviction
of a felony involving morale turpitude causing material harm to the reputation
of the Company, in each case as determined in good faith by the Company's Board
of Directors.

For the purpose of compliance with federal immigration law, you will be required
to provide to the Company documentary evidence of your identity and eligibility
for employment in the United States. This documentation must be provided to the
Company within three business days of your hire date or your employment
relationship may be terminated. In addition, as a condition of your employment,
you will be required to sign our standard Proprietary Information Agreement.

To indicate your acceptance of the Company's offer, please sign and date this
letter below and return it to me; a duplicate original is enclosed for your
records. This letter and the Proprietary Information Agreement set forth the
terms of your employment with the Company and supersede any prior representation
or agreement, whether written or oral. This letter may not be modified or
amended except by a written agreement signed by a representative of the Company
and by you.

Jim, we are all very excited about your joining SkyStream Corp. We believe that
with your background and accomplishments you are the right person to lead our
team to high levels of success. The video networking and distribution market
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MR. JAMES D. OLSON                                                 JUNE 12, 1997


will explode in the coming decade and we look forward to exploiting that
opportunity with you at SkyStream.


Very truly yours,


SKYSTREAM CORP.


/s/ GEOFFREY Y. YANG
-----------------------------
Geoffrey Y. Yang
For the Board of Directors



                                    Accepted and agreed to by:



                                    /s/ JAMES D. OLSON
                                    -----------------------------
                                    Mr. James D. Olson

                                    June 13, 1997
                                    -----------------------------
                                    Date


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Enclosure: Duplicate Original Letter