<PAGE>
 
================================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549
                                _______________

                                  FORM 10-K/A
                                AMENDMENT NO. 1
                                      TO
                                   FORM 10-K


     The undersigned Registrant hereby amends Exhibit 10.22A filed pursuant to
Item 14 of Form 10-K and files such amended exhibit herewith.

(MARK ONE)
[X]  ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE
     ACT OF 1934 [NO FEE REQUIRED]

For the fiscal year ended December 31, 1997.

[_]  OR
     TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
     EXCHANGE ACT OF 1934 [NO FEE REQUIRED]

For the transition period from    to     .

                       COMMISSION FILE NUMBER:  0-25356
                              ___________________

                                  P-COM, INC.
                               
             (Exact name of Registrant as specified in its charter)
                              ___________________         

                Delaware                            77-0289371
         (State of Incorporation)           (IRS Employer Identification No.)

            3175 S. Winchester Boulevard, Campbell, California 95008
          (Address of principal executive offices, including zip code)

      Registrant's telephone number, including area code:  (408) 866-3666
________________________________________________________________________________

SECURITIES REGISTERED PURSUANT TO SECTION 12(b) OF THE ACT:

       Title of each class          Name of each exchange on which registered
       -------------------          -----------------------------------------
              None                                     None

SECURITIES REGISTERED PURSUANT TO SECTION 12(g) OF THE ACT:  Common Stock,
$0.0001 par value. Series A Junior Participating Preferred Stock $0.0001 par
value.

     Indicate by check mark whether the registrant:  (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
Registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.  Yes   X     No _____
                                               -----           

     Indicate by a check mark if disclosure of delinquent filers pursuant to
Item 405 of Regulation S-K is not contained herein, and will not be contained,
to the best of registrant's knowledge, in definitive proxy or information
statements incorporated by reference in Part III of this Form 10-K or any
amendment to this Form 10-K.  [_]

     The aggregate market value of the voting stock held by non-affiliates of
the Registrant, as of March 23, 1998, was approximately $608,324,698 (based upon
the closing price for shares of the Registrant's Common Stock as reported by the
Nasdaq National Market for the last trading date prior to that date). Shares of
Common Stock held by each executive officer, director and holder of 5% or more
of the outstanding Common Stock have been excluded in that such persons may be
deemed to be affiliates. This determination of affiliate status is not
necessarily a conclusive determination for other purposes.

     On March 23, 1998, approximately 43,079,418 shares of the Registrant's
Common Stock, $0.0001 par value, were outstanding.

                     DOCUMENTS INCORPORATED BY REFERENCE.

     Portions of the Registrant's Proxy Statement for the 1997 Annual Meeting of
Stockholders to be held on May 19, 1998 are incorporated by reference into Part
III.

================================================================================
<PAGE>
 
                                  Form 10-K/A

                                Amendment No. 1


        The undersigned Registrant hereby amends Exhibit 10.22A filed pursuant 
to Item 15 of form 10-K and Files such amended exhibit herewith.
<PAGE>
 
                                    PART IV
                                    -------


ITEM 15.   EXHIBITS, FINANCIAL STATEMENT SCHEDULES, AND REPORTS ON FORM 8-K.



                                       2
<PAGE>
 


(c)  Exhibits - See Exhibit list below.

<TABLE>
<CAPTION>
     NUMBER        DESCRIPTION
     ------        -----------
    <C>        <S>
    *2.1(6)    Agreement dated April 15, 1996, by and among the Company, Mr.
               Giovanni Marciano and certain other parties named thereunder.

     2.2(7)    Asset Purchase Agreement dated as of August 2, 1996, by and
               between the Company, Atlantic Communication Sciences, Inc. and
               Edward c. Gerhardt, L. Roger Sanders, Charles W. Richards, IV,
               Grover W. Brower, William M. Koos, Jr., Larry W. Koos, Koos
               Technical Services, Inc., the Edward C. Gerhardt Trust. U/A dated
               June 22, 1988 and the L. Roger Sanders Revocable Trust, U/A dated
               June 18, 1991.

    *2.2A(8)   Asset Purchase Agreement revised as of August 23, 1996 by and
               between the Company, Atlantic Communication Sciences, Inc. and
               Edward C. Gerhardt, L. Roger Sanders, Charles W. Richards, IV,
               Grover W. Brower, William M. Koos, Jr., Larry W. Koos, Koos
               Technical Services, Inc., the Edward C. Gerhardt Trust, U/A dated
               June 22, 1988 and the L. Roger Sanders Revocable Trust, U/A dated
               June 18, 1991.

     2.3(19)   Escrow Agreement dated November 28, 1997, by and among P-Com,
               Inc., P-Com Field Services Inc., Telematics Inc. and Daniel N.
               Carter.

     2.4(19)   Registration Rights Agreement, dated November 17, 1997, by and
               among P-Com Field Services Inc., Telematics Inc. and Daniel N.
               Carter.

     2.5(19)   Escrow Agreement, dated November 28, 1997, by and among P-Com,
               Inc., P-Com Services (UK) Limited and R T Masts Limited.

     2.6(19)   Securities Purchase Agreement, dated November 17, 1997, by and
               among P-Com, Inc., P-Com Field Services Inc., Telematics Inc. and
               Daniel N. Carter.

     2.7(19)   Share Purchase Agreement, dated October 14, 1997, by and among P-
               Com, Inc., P-Com Services (UK) Limited and R T Masts Limited.

     3.2(3)    Restated Certificate of Incorporation filed on March 9, 1995.

     3.2A(14)  Certificate of Amendment of Restated Certificate of Incorporation
               filed on June 16, 1997.
     
    *3.2B(16)  Certificate of Designation for the Series A Junior Participating
               Preferred Stock, as filed with the Delaware Secretary of State on
               October 8, 1997.

    *3.3(1)    Bylaws of the Company.

     4.1(1)    Form of Common Stock Certificate. 4.2(18) Indenture, dated as of
               November 1, 1997, between the Registrant and State Street Bank
               and Trust Company of California, N.A., as Trustee.

     4.4(18)   Registration Rights Agreement, dated as of November 1, 1997 by
               and among the Registrant and PaineWebber Incorporated,
               BancAmerica Robertson Stephens, NationsBanc Montgomery
               Securities, Inc. and Pacific Growth Equities, Inc.

     4.5(17)   Rights Agreement, dated as of October 1, 1997, between the
               Company and BankBoston, N.A., which includes the form of
               Certificate of Designation for the Series A Junior Participating
               Preferred Stock as Exhibit A, the form of Right Certificate as
               Exhibit B and the Summary of Rights to Purchase Preferred Shares
               as Exhibit C.

     *10.1(1)  Purchase Order issued by AT&T Network Systems Deutschland GmbH,
               dated December 7, 1994.
</TABLE> 

                                       3
<PAGE>
 
<TABLE> 
<CAPTION> 
     NUMBER        DESCRIPTION
     ------        ----------- 
     <S>        <C>                                                      
    *10.2(1)    Purchase Order issued by AT&T Network Systems Deutschland GmbH,
                dated December 19, 1994.                                      
                                                                              
    *10.3(1)    Master OEM Agreement dated January 1, 1995, by and between the
                Company and AT&T Corp.                                        
                                                                              
    *10.4(1)    Purchase Order issued by AT&T Network Systems Nederland BV,
                dated December 9, 1994.                            
                                                                    
    *10.5(1)    Amendment to Purchase Order issued by AT&T Network Systems  
                Nederland BV, dated December 22, 1994.                      
                                                                            
    *10.6(1)    NSD Master Purchase Order issued by AT&T Network Systems    
                Deutschland GmbH, dated December 23, 1994.                  
                                                                            
    *10.7(1)    Purchase Agreement dated August 29, 1994, by and between the
                Company and Harris Corporation -- Farinon Division.         
                                                                            
    *10.8(1)    Contract for Supply of 50 GHz Radio dated June 4, 1994, by and
                between the Registrant and Mercury Communications Ltd.        
                                                                              
    *10.9(1)    Manufacturing Agreement dated July 13, 1994, by and between the
                Company and SPC.                                              
                                                                              
    *10.10(1)   Manufacturing Agreement dated April 20, 1994, by and between the
                Company and Comptronix Corporation (assigned to Sanmina   
                Corporation).                                             
                                                                          
    *10.11(1)   Agreement dated November 11, 1994, by and between the Company
                and WinStar Wireless, Inc.                                   
                                                                             
     10.12(1)   Master Lease Agreement dated November 9, 1992, by and between
                the Company and Dominion; First Amendment to Master Lease    
                Agreement dated June 23, 1993, by and between the Company and 
                Dominion.                                                     
                                                                              
     10.13(1)   Master Equipment Lease entered into by and between the Company
                and Phoenix Leasing Incorporated on August 10, 1994.          

    *10.14(1)   Commitment Letter dated January 10, 1995, by and between the 
                Company and Applied Telecommunications Technologies, Inc.    
                ("ATTI"), including form of Master Lease to be entered into  
                between the Company and ATTI.                                
                                                                             
    *10.15D     Accounts Receivable Purchase Agreement dated December 31, 1997
                by and between the Company and Wells Fargo MCBC Trade Bank N.A.
                                                                             
     10.16A(7)  1995 Stock Option/Stock Issuance Plan, including forms of
                Notices of Grant of Automatic Stock Option for initial grant and
                annual grants and Automatic Stock Option Agreement, as amended.
     
     10.16B(13) 1995 Stock Option/Stock Issuance Plan, including forms of  
                Notices of Grant of Automatic Stock Option for initial grant and
                annual grants and Automatic Stock Option Agreement, as amended.
     
    *10.17(1)   Employee Stock Purchase Plan, including forms of Stock Purchase
                Agreement and Enrollment/Change Form.

    *10.17B(13) Employee Stock Purchase Plan, as amended.                  
                                                                           
    *10.18(1)   Form of Indemnification Agreement by and between the Company and
                each of its officers and directors and a list of signatories.

     10.19A     Service Agreement dated December 15, 1997 by and between the  
                Company and Mr. George P. Roberts.                            
                                                                              
     10.19B     Service Agreement dated December 15, 1997 by and between the  
                Company and1 0.19B Mr. Michael J. Sophie.                     
                                                                              
     10.19C     Service Agreement dated December 15, 1997 by and between the  
                Company and Mr. Pier Antoniucci.                              
                                                                              
    *10.21(1)   Real Property Lease dated December 10, 1993, by and between the
                Company and Bryan T.D. Trust, pertaining to 3175 S. Winchester
                Boulevard, Campbell, California 95008.                        
                                                                              
    *10.22(1)   Low Capacity Digital Radio Product Agreement dated February 13,
                1995 by and between the Company and Siemens.             
                                                                         
    *10.22A     Low Capacity Digital Radio Agreement dated February 13, 1995
                band between the Company and Itatel.                       
</TABLE> 
                     
                                      4
<PAGE>
 
<TABLE> 
<CAPTION> 
     NUMBER        DESCRIPTION
     ------        -----------
     <S>        <C>  
    *10.23(3)   Sublease dated May 1, 1995 by and between the Company and
                Medallion Mortgage Company.

    *10.24(4)   Lease dated August 4, 1995 by and between P-COM United Kingdom,
                Inc. and Capital Counties plc; Rent Deposit Deed dated August 4,
                1995, by and between P-Com United Kingdom, Inc. and Capital
                Counties plc.

    *10.25(2)   Underwriting Agreement dated March 2, 1995 by and between the
                Company and the underwriters named therein.

    *10.26(5)   Underwriting Agreement dated August 17, 1995 by and between the
                Company and the underwriters named therein.

    *10.27(9)   Lease dated November 11, 1995 by and between the Company, Inc.
                and Johann Birkart, Internationale Spedition GmbH & Co.

     10.30A(11) Loan Agreement dated March 3, 1997 by and between the Company
                and Union Bank of California, N.A.

     10.30B(11) Amendment dated May 7, 1997 to the Loan Agreement dated March 3,
                1997 by and between the Company and Union Bank of California,
                N.A.

     10.30C(13) Amended and Restated Loan Agreement dated September 17, 1997 by
                and between the Company and Union Bank of California, N.A.

     11.1       Computation of Pro Forma Net Income (Loss) Per Share.

     21.1       List of subsidiaries of the Registrant.

     23.1       Consent of Price Waterhouse LLP, Independent Accountants.

     24.1       Power of Attorney (see page 63).

     27         Financial Data Schedule
</TABLE>

________________
(1)  Incorporated by reference to identically numbered exhibits included in the
     Company's Registration Statement on Form S-1 (File No. 33-88492) declared
     effective with the Securities and Exchange Commission on March 2, 1995.

(2)  Incorporated by reference to Exhibit 1.1 to the Company's Registration
     Statement on Form S-1 (File No. 33-88492) declared effective with the
     Securities and Exchange Commission on March 2, 1995.

(3)  Incorporated by reference to identically numbered exhibits included in the
     Company's Registration Statement on Form S-1 (File No. 33-95392) declared
     effective with the Securities and Exchange Commission on August 17, 1995.

(4)  Incorporated by reference to identically numbered exhibits included in the
     Company's Quarterly Report on Form 10-Q filed with the Securities and
     Exchange Commission on  November 1, 1996.

(5)  Incorporated by reference to Exhibit 1.1 to the Company's Registration
     Statement on Form S-1 (File No. 33-95392) declared effective with the
     Securities and Exchange Commission on August 17, 1995.

(6)  Incorporated by reference to identically numbered exhibits included in the
     Company's Registration Statement on Form S-3 declared effective with the
     Securities and Exchange Commission on May 16, 1996 (File No. 333-3558).

(7)  Incorporated by reference to identically numbered exhibits to the Company's
     Quarterly Report on Form 10-Q for the quarterly period ended June 30, 1996.

(8)  Incorporated by reference to identically numbered exhibits to the Company's
     Quarterly Report on Form 10-Q for the quarterly period ended September 30,
     1996.

(9)  Incorporated by reference to identically numbered exhibits to the Company's
     Annual Report on Form 10-K for the annual period ended December 31, 1995.

                                       5
<PAGE>
 
(10) Incorporated by reference to Exhibit 1.1 to the Company's Registration
     Statement on Form S-3 declared effective with the Securities and Exchange
     Commission on May 16, 1996 (File No. 333-3558).

(11) Incorporated by reference to identically numbered exhibits to the Company's
     Quarterly Report on Form 10-Q for the quarterly period ended March 31,
     1996.

(12) Incorporated by reference to identically numbered exhibits to the Company's
     Quarterly Report on Form 10-Q for the quarterly period ended March 31,
     1997.

(13) Incorporated by reference to identically numbered exhibits to the Company's
     Quarterly Report on Form 10-Q for the quarterly period ended June 30, 1997.

(14) Incorporated by reference to Exhibit 3.3 to the Company's Quarterly Report
     on Form 10-Q for the quarterly period ended June 30, 1996.

(15) Incorporated by reference to identically numbered exhibits to the Company's
     Quarterly Report on Form 10-Q for the quarterly period ended September 30,
     1997.

(16) Incorporated by reference to Exhibit 3 to the Company's Quarterly Report on
     Form 10-Q for the quarterly period ended September 30, 1997.

(17) Incorporated by reference to Exhibit 4 to the Company's Quarterly Report on
     Form 10-Q for the quarterly period ended September 30, 1997.

(18) Incorporated by reference to identically numbered exhibits included in the
     Company's Registration Statement on Form S-3 (File No. 333-45463) filed
     with the Securities and Exchange Commission on February 2, 1998.

(19) Previously filed as an exhibit to the Company's Current Report on Form 8-K
     dated December 10, 1997 as filed with the Securities and Exchange
     Commission on November 28, 1997 (File No. 001-13475).

*  Confidential treatment granted as to certain portions of these exhibits.

                                       6
<PAGE>
 
                                 SIGNATURES


      Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the registrant has duly caused this report to be signed on
its behalf by the undersigned, thereunto duly authorized, on May 5, 1998.

                                 P-COM, INC.


Date: May 5, 1998        By: /s/ George P. Roberts
                             ---------------------
                             George P. Roberts
                             Chairman of the Board and Chief Executive Officer
                             (Principal Executive Officer)
                             


Date: May 5, 1998        By: /s/ Michael Sophie
                             --------------------    
                             Michael Sophie
                             Chief Financial Officer and Vice President, Finance
                             and Administration (Principal Financial and 
                             Accounting Officer)
                                 
                                

                                       7
<PAGE>
 
     Pursuant to the requirements of the Securities Exchange Act of 1934, this
report has been signed below by the following persons on behalf of the
Registrant and in the capacities and on the dates indicated.


Date: May 5, 1998              By  /s/ George P. Roberts
                                   ------------------------------
                                   George P. Roberts
                                   Chairman of the Board and
                                   Chief Executive Officer
 


Date: May 5, 1998              By: /s/ Michael Sophie
                                   ------------------------------
                                   Michael Sophie
                                   Chief Financial Officer, Vice President,
                                   Finance and Administration


Date: May 5, 1998               By:               *
                                   -----------------------------
                                   Gill Cogan
                                   Director of the Company


Date: May 5, 1998              By:               *
                                   -----------------------------
                                   John A. Hawkins
                                   Director of the Company


Date: May 5, 1998              By:               *
                                   -----------------------------
                                   M. Bernard Puckett
                                   Director of the Company


Date: May 5, 1998              By:               *
                                   ------------------------------ 
                                   M. James J. Sobczak
                                   Director of the Company



* By:  George P. Roberts and Michael Sophie, attorneys-in-fact


                                       8