UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549


|X| Form 10-K   |_| Form 20-F   |_| Form 11-K    |_| Form 10-Q   |_| Form N-SAR

For Period Ended: MARCH 31, 1999

|_|      Transition Report on Form 10-K
|_|      Transition Report on Form 20-F
|_|      Transition Report on Form 11-K
|_|      Transition Report on Form 10-Q
|_|      Transition Report on Form N-SAR

For the Transition Period Ended:

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  Read Instruction (on back page) Before Preparing Form. Please Print or Type.

            Nothing in this form shall be construed to imply that the
            Commission has verified any information contained herein.
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 If the notification relates to a portion of the filing checked above, identify
                 the item(s) to which the notification relates:

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PART I      REGISTRATION INFORMATION
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Full Name of Registrant:                        COYOTE NETWORK SYSTEMS, INC.

Former Name if Applicable:                      THE DIANA CORPORATION

Address of Principal Executive Office:          4360 Park Terrace Drive

City, State and Zip Code:                       Westlake Village, CA 91361

PART II     RULES 12b-25(b) AND (c)
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If the subject report could not be filed without  unreasonable effort or expense
and the registrant seeks relief pursuant to Rule 12b-25(b), the following should
be completed. (Check box if appropriate)

|X|   (a)   The reasons  described in reasonable detail in Part III of this form
            could not be eliminated without unreasonable effort or expense;


      (b)   The subject annual report,  semi-annual report, transition report on
            Form 10-K, Form 20-F, 11-K, Form N-SAR, or portion thereof,  will be
            filed on or before the fifteenth  calendar  following the prescribed
            due date; or the subject  quarterly  report of transition  report on
            Form 10-Q,  or portion  thereof will be filed on or before the fifth
            calendar  day  following  the  prescribed  due  date;  and

      (c)   The  accountant's  statement  or other  exhibit  required by Rule
            12b-25(c) has been attached if applicable.


PART III    NARRATIVE
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State below in  reasonable  detail the reasons  why the Form 10-K,  11-K,  10-Q,
N-SAR, or the transition  report or portion  thereof,  could not be filed within
the prescribed time period. (Attach extra sheets if needed.)

          The Company has recently completed a private placement of common stock
     and a redemption of convertible  preferred  stock.  These  activities  have
     caused a delay in the  preparation of the financial  statements and related
     disclosures which, when completed,  will enable filing of the FORM 10-K. It
     is  expected  that the  filing  can be made  within  the  extension  period
     described in this form.


PART IV     OTHER INFORMATION
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(1)   Name  and  telephone  number  of  person  to  contact  in  regard  to this
      notification:                              Brian A. Robson (818) 735-7600

(2)   Have all other periodic  reports required under Section 13 or 15(d) of the
      Securities  Exchange Act of 1934 or Section 30 of the  Investment  Company
      Act of 1940 during the preceding 12 months or for such shorter period that
      the registrant  was required to file such report(s) been filed?  If answer
      is no, identify report(s).                                  |X| YES |_| NO

(3)   Is it  anticipated  that any  significant  change in results of operations
      from the  corresponding  period for the last fiscal year will be reflected
      by the earnings  statement to be included in the subject report or portion
      thereof?                                                    |X| YES |_| NO

If so, attach an explanation of the  anticipated  change,  both  narratively and
quantitatively, and, if appropriate, state the reasons why a reasonable estimate
of the results cannot be made.

          The Company expects to report revenues of aproximately $43 million and
     a net loss of approximately $14 million for the fiscal year ended March 31,
     1999,  compared to revenues of $5 million and a net loss of $34 million for
     the prior year ended March 31, 1998.

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                          COYOTE NETWORK SYSTEMS, INC.
                  (Name of Registrant as Specified in Charter)

         has caused this notification to be signed on its behalf by the
                     undersigned hereunto duly authorized.

Date:    June 29, 1999

By:
         /s/ Brian A. Robson
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         Brian A. Robson
         Executive Vice President and Chief Financial Officer

INSTRUCTION: The form may be signed by an executive officer of the registrant or
by any other duly  authorized  representative.  The name and title of the person
signing  the form  shall  be typed or  printed  beneath  the  signature.  If the
statement is signed on behalf of the registrant by an authorized  representative
(other than an executive officer), evidence of the representative's authority to
sign on behalf of the registrant shall be filed with the form.

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                                    ATTENTION
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Intentional  misstatements  or omissions  of fact  constitute  Federal  Criminal
Violations (See 18 U.S.C. 1001)