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                                                                   EXHIBIT 10.77

                                PROMISSORY NOTE
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                                                            Date: May 3, 2000
   $250,000

        Promise to Pay. FOR VALUE RECEIVED, James Sobczak, an individual
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   residing in the State of California (the "Borrower"), promises to pay to the
   order of P-COM, INC. (the "Holder") the principal sum of Two Hundred Fifty
   Thousand Dollars and 00/100 ($250,000), without interest thereon, payable in
   full on the first anniversary of Borrower's voluntary or involuntary
   termination from Holder. Borrower agrees that time is of the essence and if
   this Note is not paid when due, whether at stated maturity or by
   acceleration, interest shall then accrue on the unpaid principal of this Note
   at the rate of twelve percent (12%) per annum, compounded monthly during such
   period of default for so long as such event of default continues. The
   principal and interest represented by this Note shall be payable in
   immediately available fund in lawful money of the United States which shall
   be legal tender for public and private debts at the time of payment. All
   payments hereunder shall be payable to the order of Holder at 3175 S.
   Winchester Boulevard, Campbell, California 95008, or to such person as shall
   be designated in writing from time to time by Holder. Payments received by
   Holder shall be applied first to the collection expenses incurred by Holder,
   then to interest, if any, and the balance, to principal.

        Prepayment. Borrower may prepay without permission or penalty all or any
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   portion of the principal balance of this Note.

        Costs. Borrower promises to pay all costs incurred by Holder in the
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   collection of this Note, including but not limited to reasonable attorneys'
   fees and expenses.

        Default  Borrower shall be in default (an "Event of Default") under this
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   Note on the occurrence of any of the following: (a) non-payment of any
   principal amount when due under this Note; (b) Borrower (i) admitting
   insolvency or an inability to pay her debts as they mature, (ii) making a
   general assignment for the benefit of creditors, (iii) commencing a case
   under or otherwise seeking to take advantage of any bankruptcy,
   reorganization, insolvency, readjustment of debt, dissolution or liquidation
   law, statute or proceeding, (iv) by any act indicating his consent to,
   approval of or acquiescence in any such proceeding or the appointment of any
   receiver of or trustee for her or a substantial part of her property or
   suffering any such receivership, trusteeship or proceeding to continue
   without dismissal for a period of thirty (30) days, or (v) becoming a debtor
   in any case under any chapter of the applicable Bankruptcy Code; (c) the
   occurrence of a material adverse change in the financial condition of
   Borrower which is not cured within ten (10) days of the date of notice from
   Holder to Borrower with respect to such occurrence; (d) the death of the
   undersigned. Upon the occurrence of any Event of Default, the Holder, at its
   sole option, may accelerate the due date of and declare the unpaid balance of
   this Note to be immediately due and payable without notice, presentation,
   demand of payment or protest, all of which are hereby expressly waived by the
   Borrower.

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        Remedies. BORROWER HEREBY EXPRESSLY WAIVES ANY RIGHT TO A TRIAL BY JURY
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   IN CONNECTION WITH ANY SUIT BROUGHT UNDER THIS NOTE BY HOLDER. Borrower
   hereby (i) agrees to waive any and all lack of diligence or delays in the
   collection or enforcement hereof and (ii) expressly consents to any extension
   of time for payment of this Note and any other indulgence or forbearance by
   Holder. Any such extension, release, substitution, indulgence, or forbearance
   may be made without notice to any party and without in any way affecting the
   personal liability of any party liable hereon. Borrower waives notice, demand
   for payment and presentment.

        Notice. Any notice or legal process or summons to Borrower where
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   provided for in this Note shall be given by mailing such notice by certified
   mail, return receipt requested, to Borrower at 1110 Petrini Way, San Jose,
   California 95120 or to such other address Borrower may designate by written
   notice to Holder hereof. Any notice to the Holder hereof shall be given by
   mailing such notice by certified mail, return receipt requested, to the
   Holder at 3175 S. Winchester Boulevard, Campbell, California 95008, or at
   such other address as may have been designated by written notice to Borrower.

        Miscellaneous. This Note shall be binding upon Borrower and his heirs
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   and successors and shall inure to the benefit of Holder and its successors
   and assigns. Any modifications to this Note shall be in writing and signed by
   the Borrower and the Holder. This Note is executed and delivered in and shall
   be governed by and construed in accordance with the laws of the State of
   California. Borrower hereby consents to the in personam jurisdiction of any
   court sitting in Santa Clara County.  In the event that any particular
   provision contained herein is determined to be invalid, whether in whole or
   in part, the remaining provisions hereof otherwise not invalid and any
   partially valid provision to the extent valid or enforceable shall continue
   in full force and effect. Any reference herein to the singular shall include
   the plural, any reference to the masculine shall include the feminine gender,
   and any reference to "it" shall include "his," or vice versa, as the case may
   be.

        IN WITNESS WHEREOF, the undersigned, with full power and authority to do
   so, has
   caused these presents to be executed and delivered on the day and year first
   above written.


   ATTEST:                                BORROWER:

   /s/ Caroline Baldwin Kahl              /s/ James Sobczak
   -------------------------              -----------------------
   Name: Caroline Baldwin Kahl            JAMES SOBCZAK
   Title: Corporate General Counsel

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