<PAGE>
 
          As filed with the Securities and Exchange Commission on April __, 1999
                                                  Registration No. 333-_________

      --------------------------------------------------------------------------

                      SECURITIES AND EXCHANGE COMMISSION

                            Washington, D.C.  20549

                                   FORM S-8
                            REGISTRATION STATEMENT
                                     UNDER
                          THE SECURITIES ACT OF 1933

                             DYNATECH CORPORATION
                             --------------------
              (Exact name of issuer as specified in its charter)

                    Massachusetts                             04-2258582
         --------------------------------              ---------------------
         (State or other jurisdiction of                 (I.R.S. Employer
         incorporation or organization)                  Identification No.)

              3 New England Executive Park, Burlington, MA  01803
          -----------------------------------------------------------
             (Address of principal executive offices)  (Zip Code)

                             DYNATECH CORPORATION
                             AMENDED AND RESTATED
                     1994 STOCK OPTION AND INCENTIVE PLAN

                             DYNATECH CORPORATION
                            NON-EMPLOYEE DIRECTORS
                             STOCK INCENTIVE PLAN
                 --------------------------------------------
                           (Full title of the plan)


                           Mark V. B. Tremallo, Esq.
                             Dynatech Corporation
                         3 New England Executive Park
                     Burlington, Massachusetts  01803-5087
                 --------------------------------------------
                    (Name and address of agent for service)


                                (781) 272-6100
          -----------------------------------------------------------
         (Telephone number, including area code, of agent for service)

                        CALCULATION OF REGISTRATION FEE
                        -------------------------------


   Title of                     Proposed       Proposed
  Securities                    Maximum        Maximum
    to be      Amount to be  Offering Price   Aggregate            Amount of
  Registered   Registered     Per Share(1)   Offering Price(1)  Registration Fee
------------- ------------- --------------- ------------------  ----------------
Common Stock,   36,864,200       $3.40625    $125,568,681.30       $34,908.09
No par value    shares


____________________
   (1)  Estimated solely for the purpose of calculating the registration fee,
and based on the average of the high and low prices as reported by the NASDAQ
National Market on March 31, 1999, in accordance with Rules 457(c) and (h) of
the Securities Act of 1933, as amended.
<PAGE>
 
PART I.  INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

      The information required by Part I is included in documents sent or given
to participants in the Dynatech Corporation Amended and Restated 1994 Stock
Option and Incentive Plan and the Dynatech Corporation Non-Employee Directors
Stock Incentive Plan, a Massachusetts corporation (the "Registrant"), pursuant
to Rule 428(b)(1) of the Securities Act of 1933, as amended (the "Securities
Act").

PART II. INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

      Item 3.  Incorporation of Certain Documents by Reference.
               ----------------------------------------------- 

      The Registrant is subject to the informational and reporting requirements
of Sections 13(a), 14 and 15(d) of the Securities Exchange Act of 1934, as
amended (the "Exchange Act"), and in accordance therewith files reports, proxy
statements and other information with the Securities and Exchange Commission.
The following documents, which are filed with the Securities and Exchange
Commission, are incorporated in this Registration Statement by reference:

         (1) The Registrant's latest annual report filed pursuant to Sections
      13(a) or 15(d) of the Exchange Act or the latest prospectus filed pursuant
      to Rule 424(b) under the Securities Act that contains audited financial
      statements for the Registrant's latest fiscal year for which such
      statements have been filed.

         (2) All other reports filed pursuant to Sections 13(a) or 15(d) of the
      Exchange Act since the end of the fiscal year covered by the document
      referred to in (1) above.

         (3) The description of the Common Stock, no par value per share
      ("Common Stock"), contained in a registration statement filed under the
      Exchange Act, including any amendment or report filed for the purpose of
      updating such description.

      All documents subsequently filed by the Registrant pursuant to Sections
13(a), 13(c), 14 and 15(d) of the Exchange Act prior to the filing of a post-
effective amendment which indicates that all shares of Common Stock offered
hereby have been sold or which deregisters all shares of Common Stock then
remaining unsold, shall be deemed to be incorporated by reference herein and to
be part hereof from the date of the filing of such documents.

      Item 4.  Description of Securities.
               ------------------------- 

      Not applicable.

      Item 5.  Interests of Named Experts and Counsel.
               -------------------------------------- 

      The validity of the Common Stock will be passed upon for the Company by
Mark V.B. Tremallo, its General Counsel.
<PAGE>
 
      Item 6.  Indemnification of Directors and Officers.
               ----------------------------------------- 

      The Company's Articles of Organization (the "Articles") provide that
except as limited by law, the Company shall indemnify its directors and officers
against all expenses incurred by them in connection with any proceeding
resulting from their serving as an officer or director, except that no
indemnification shall be provided regarding any matter as to which it shall be
adjudicated that such director or officer did not act in good faith and in the
reasonable belief that his or her action was in the best interests of the
Company.  In addition, the Articles provide that no director of the Company
shall be personally liable to the Company or its stockholders for monetary
damages for breach of fiduciary duty as a director notwithstanding any
provisions of law imposing such liability; provided, however, that such
provision shall not eliminate or limit the liability of a director (i) for any
breach of the director's duty of loyalty to the Company or its stockholders,
(ii) for acts or omissions not in good faith or which involve intentional
misconduct or a knowing violation of law, (iii) under Section 61 or 62 of the
Business Corporation Law of the Commonwealth of Massachusetts, or (iv) with
respect to any transaction from which the director derived an improper personal
benefit.

      The Company maintains directors' and officers' liability insurance for the
benefit of its directors and certain of its officers.

      Item 7.  Exemption from Registration Claimed.
               ----------------------------------- 

      Not applicable.

      Item 8.  Exhibits.
               -------- 

      The Exhibit Index immediately preceding the exhibits is incorporated
herein by reference.

      Item 9.  Undertakings.
               ------------ 

      1. The Registrant hereby undertakes:

         (a)   To file, during any period in which offers or sales are being
      made, a post-effective amendment to this Registration Statement:

         (i)   To include any prospectus required by Section 10(a)(3) of the
               Securities Act;

         (ii)  To reflect in the prospectus any facts or events arising after
               the effective date of the Registration Statement (or the most
               recent post-effective amendment thereof) which, individually or
               in the aggregate, represent a fundamental change in the
               information set forth in the Registration Statement; and

         (iii) To include any material information with respect to the plan of
               distribution not previously disclosed in the Registration
               Statement or any material change to such information in the
               Registration Statement;

                                       2
<PAGE>
 
      PROVIDED, HOWEVER, that paragraphs (i) and (ii) do not apply if the
      Registration Statement is on Form S-3 or Form S-8, and the information
      required to be included in a post-effective amendment by those paragraphs
      is contained in periodic reports filed by the Registrant pursuant to
      Section 13 or Section 15(d) of the Exchange Act that are incorporated by
      reference in the Registration Statement.

         (b) That, for the purpose of determining any liability under the
      Securities Act, each such post-effective amendment shall be deemed to be a
      new registration Statement relating to the securities offered therein,
      and the offering of such securities at that time shall be deemed to be the
      initial bona fide offering thereof.

         (c) To remove from registration by means of a post-effective amendment
      any of the securities being registered which remain unsold at the
      termination of the offering.

      2. The Registrant hereby undertakes that, for purposes of determining any
liability under the Securities Act, each filing of the Registrant's annual
report pursuant to Section 13(a) or Section 15(d) of the Exchange Act (and,
where applicable, each filing of an employee benefit plan's annual report
pursuant to Section 15(d) of the Exchange Act) that is incorporated by reference
in the Registration Statement shall be deemed to be a new Registration Statement
relating to the securities offered therein, and the offering of such securities
at that time shall be deemed to be in the initial bona fide offering thereof.

      3. Insofar as indemnification for liabilities arising under the Securities
Act may be permitted to directors, officers and controlling persons of the
Registrant pursuant to the foregoing provisions, or otherwise, the Registrant
has been advised that in the opinion of the Securities and Exchange Commission
such indemnification is against public policy as expressed in the Securities Act
and is, therefore, unenforceable.  In the event that a claim for indemnification
against such liabilities (other than the payment by the Registrant of expenses
incurred or paid by a director, officer or controlling person of the Registrant
in the successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the Registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the Securities Act and will be governed by the final
adjudication of such issue.

                                       3
<PAGE>
 
                                   SIGNATURES

      Pursuant to the requirements of the Securities Act of 1933, the registrant
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-8 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Burlington, Commonwealth of Massachusetts, on
___________, 1999.

                                        DYNATECH CORPORATION


                                        By:
                                            _________________________________
                                            John F. Reno
                                            Chairman, President and
                                            Chief Executive Officer

                                       4
<PAGE>
 
      Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed below by the following persons in the
capacities and on the dates indicated.
<TABLE>
<CAPTION>
        Signatures                               Capacity                                  Date
---------------------------------    -----------------------------------   ------------------------------------
 
<S>                                  <C>                                   <C>
                                     Chairman of the Board of              
_________________________________    Directors, President, Chief           ____________________________, 1999
John F. Reno                         Executive Officer and
                                     Director
                                     
                                     
                                     
                                     Vice President, Chief
                                     Financial Officer, Treasurer
_________________________________    (Principal Financial Officer),        ____________________________, 1999
Allan M. Kline                       and Director
                                     
                                     
                                     
                                     Corporate Vice President -
_________________________________    Communications Test                   ____________________________, 1999
John R. Peeler                       Business, and Director
                                     

_________________________________                                          ____________________________, 1999
Brian D. Finn                        Director
                       
                                     
_________________________________    Director                              ____________________________, 1999
Charles P. Pieper                    

                                     
_________________________________    Director                              ____________________________, 1999
Joseph L. Rice, III                  
                                     

_________________________________    Director                              ____________________________, 1999
Ned C. Lautenbach                    

                                     
_________________________________    Director                              ____________________________, 1999
Brian H. Rowe                        
                                     

_________________________________    Director                              ____________________________, 1999
Marvin L. Mann
</TABLE> 

                                       5
<PAGE>
 
                                   EXHIBIT INDEX
                                   -------------

<TABLE> 
<CAPTION> 
  Exhibit                                                                                      Sequential
  Number                                                                                       Page Number
----------                                                                                    -------------
<S>           <C>                                                                             <C> 
3.1           Amended and Restated Articles of Organization of the                                  --
              Registrant - filed as Exhibit 3(1) to the Registrant's
              Annual Report on 10-K for the fiscal year ended
              March 31, 1998 and incorporated herein by reference.

3.2           By-Laws filed as Exhibit 3.2(ii) to the Registrant's                                  --
              Annual Report on Form 10-K for the fiscal year ended
              March 31, 1998 and incorporated herein by reference.

4.1           Specimen Certificate of Common Stock of the                                           --
              Registrant (filed herein).

5             Opinion of Mark V. B. Tremallo, Dynatech                                              --
              Corporation's General Counsel (filed herein)

23.1          Consent of Mark V.B. Tremallo, Dynatech                                               --
              Corporation's General Counsel's consent is stated with
              said counsel's opinion as Exhibit No. 5 (filed herein)

23.2          Consent of PricewaterhouseCoopers L.L.P. (filed                                       --
              herein)

24            Power of Attorney (filed herein).                                                     --

99(i)         Dynatech Corporation Amended and Restated 1994                                        --
              Stock Option and Incentive Plan (filed herein)

99(ii)        Dynatech Corporation Non-Employee Directors Stock                                     --
              Incentive Plan (filed herein).
</TABLE>
[{"type": "S-8", "sequence": "1", "description": "FORM S-8", "secsgml_size_bytes": 17209}]
{"company-data": {"conformed-name": "DYNATECH CORP", "cik": "0000030841", "assigned-sic": "3825", "irs-number": "042258582", "state-of-incorporation": "MA", "fiscal-year-end": "0331"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-75797", "film-number": "99588622"}, "business-address": {"street1": "3 NEW ENGLAND EXECUTIVE PARK", "city": "BURLINGTON", "state": "MA", "zip": "01803-5087", "phone": "6172726100"}, "mail-address": {"street1": "3 NEW ENGLAND EXECUTIVE PARK", "city": "BURLINGTON", "state": "MA", "zip": "01803-5087"}}
As filed with the Securities and Exchange Commission on April __, 1999
                                                  Registration No. 333-_________

      --------------------------------------------------------------------------

                      SECURITIES AND EXCHANGE COMMISSION

                            Washington, D.C.  20549

                                   FORM S-8
                            REGISTRATION STATEMENT
                                     UNDER
                          THE SECURITIES ACT OF 1933

                             DYNATECH CORPORATION
                             --------------------
              (Exact name of issuer as specified in its charter)

                    Massachusetts                             04-2258582
         --------------------------------              ---------------------
         (State or other jurisdiction of                 (I.R.S. Employer
         incorporation or organization)                  Identification No.)

              3 New England Executive Park, Burlington, MA  01803
          -----------------------------------------------------------
             (Address of principal executive offices)  (Zip Code)

                             DYNATECH CORPORATION
                             AMENDED AND RESTATED
                     1994 STOCK OPTION AND INCENTIVE PLAN

                             DYNATECH CORPORATION
                            NON-EMPLOYEE DIRECTORS
                             STOCK INCENTIVE PLAN
                 --------------------------------------------
                           (Full title of the plan)

                           Mark V. B. Tremallo, Esq.
                             Dynatech Corporation
                         3 New England Executive Park
                     Burlington, Massachusetts  01803-5087
                 --------------------------------------------
                    (Name and address of agent for service)

                                (781) 272-6100
          -----------------------------------------------------------
         (Telephone number, including area code, of agent for service)

                        CALCULATION OF REGISTRATION FEE
                        -------------------------------

   Title of                     Proposed       Proposed
  Securities                    Maximum        Maximum
    to be      Amount to be  Offering Price   Aggregate            Amount of
  Registered   Registered     Per Share(1)   Offering Price(1)  Registration Fee
------------- ------------- --------------- ------------------  ----------------
Common Stock,   36,864,200       $3.40625    $125,568,681.30       $34,908.09
No par value    shares

____________________
   (1)  Estimated solely for the purpose of calculating the registration fee,
and based on the average of the high and low prices as reported by the NASDAQ
National Market on March 31, 1999, in accordance with Rules 457(c) and (h) of
the Securities Act of 1933, as amended.
PART I.  INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS

      The information required by Part I is included in documents sent or given
to participants in the Dynatech Corporation Amended and Restated 1994 Stock
Option and Incentive Plan and the Dynatech Corporation Non-Employee Directors
Stock Incentive Plan, a Massachusetts corporation (the "Registrant"), pursuant
to Rule 428(b)(1) of the Securities Act of 1933, as amended (the "Securities
Act").

PART II. INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

      Item 3.  Incorporation of Certain Documents by Reference.
               ----------------------------------------------- 

      The Registrant is subject to the informational and reporting requirements
of Sections 13(a), 14 and 15(d) of the Securities Exchange Act of 1934, as
amended (the "Exchange Act"), and in accordance therewith files reports, proxy
statements and other information with the Securities and Exchange Commission.
The following documents, which are filed with the Securities and Exchange
Commission, are incorporated in this Registration Statement by reference:

         (1) The Registrant's latest annual report filed pursuant to Sections
      13(a) or 15(d) of the Exchange Act or the latest prospectus filed pursuant
      to Rule 424(b) under the Securities Act that contains audited financial
      statements for the Registrant's latest fiscal year for which such
      statements have been filed.

         (2) All other reports filed pursuant to Sections 13(a) or 15(d) of the
      Exchange Act since the end of the fiscal year covered by the document
      referred to in (1) above.

         (3) The description of the Common Stock, no par value per share
      ("Common Stock"), contained in a registration statement filed under the
      Exchange Act, including any amendment or report filed for the purpose of
      updating such description.

      All documents subsequently filed by the Registrant pursuant to Sections
13(a), 13(c), 14 and 15(d) of the Exchange Act prior to the filing of a post-
effective amendment which indicates that all shares of Common Stock offered
hereby have been sold or which deregisters all shares of Common Stock then
remaining unsold, shall be deemed to be incorporated by reference herein and to
be part hereof from the date of the filing of such documents.

      Item 4.  Description of Securities.
               ------------------------- 

      Not applicable.

      Item 5.  Interests of Named Experts and Counsel.
               -------------------------------------- 

      The validity of the Common Stock will be passed upon for the Company by
Mark V.B. Tremallo, its General Counsel.
Item 6.  Indemnification of Directors and Officers.
               ----------------------------------------- 

      The Company's Articles of Organization (the "Articles") provide that
except as limited by law, the Company shall indemnify its directors and officers
against all expenses incurred by them in connection with any proceeding
resulting from their serving as an officer or director, except that no
indemnification shall be provided regarding any matter as to which it shall be
adjudicated that such director or officer did not act in good faith and in the
reasonable belief that his or her action was in the best interests of the
Company.  In addition, the Articles provide that no director of the Company
shall be personally liable to the Company or its stockholders for monetary
damages for breach of fiduciary duty as a director notwithstanding any
provisions of law imposing such liability; provided, however, that such
provision shall not eliminate or limit the liability of a director (i) for any
breach of the director's duty of loyalty to the Company or its stockholders,
(ii) for acts or omissions not in good faith or which involve intentional
misconduct or a knowing violation of law, (iii) under Section 61 or 62 of the
Business Corporation Law of the Commonwealth of Massachusetts, or (iv) with
respect to any transaction from which the director derived an improper personal
benefit.

      The Company maintains directors' and officers' liability insurance for the
benefit of its directors and certain of its officers.

      Item 7.  Exemption from Registration Claimed.
               ----------------------------------- 

      Not applicable.

      Item 8.  Exhibits.
               -------- 

      The Exhibit Index immediately preceding the exhibits is incorporated
herein by reference.

      Item 9.  Undertakings.
               ------------ 

      1. The Registrant hereby undertakes:

         (a)   To file, during any period in which offers or sales are being
      made, a post-effective amendment to this Registration Statement:

         (i)   To include any prospectus required by Section 10(a)(3) of the
               Securities Act;

         (ii)  To reflect in the prospectus any facts or events arising after
               the effective date of the Registration Statement (or the most
               recent post-effective amendment thereof) which, individually or
               in the aggregate, represent a fundamental change in the
               information set forth in the Registration Statement; and

         (iii) To include any material information with respect to the plan of
               distribution not previously disclosed in the Registration
               Statement or any material change to such information in the
               Registration Statement;

                                       2
PROVIDED, HOWEVER, that paragraphs (i) and (ii) do not apply if the
      Registration Statement is on Form S-3 or Form S-8, and the information
      required to be included in a post-effective amendment by those paragraphs
      is contained in periodic reports filed by the Registrant pursuant to
      Section 13 or Section 15(d) of the Exchange Act that are incorporated by
      reference in the Registration Statement.

         (b) That, for the purpose of determining any liability under the
      Securities Act, each such post-effective amendment shall be deemed to be a
      new registration Statement relating to the securities offered therein,
      and the offering of such securities at that time shall be deemed to be the
      initial bona fide offering thereof.

         (c) To remove from registration by means of a post-effective amendment
      any of the securities being registered which remain unsold at the
      termination of the offering.

      2. The Registrant hereby undertakes that, for purposes of determining any
liability under the Securities Act, each filing of the Registrant's annual
report pursuant to Section 13(a) or Section 15(d) of the Exchange Act (and,
where applicable, each filing of an employee benefit plan's annual report
pursuant to Section 15(d) of the Exchange Act) that is incorporated by reference
in the Registration Statement shall be deemed to be a new Registration Statement
relating to the securities offered therein, and the offering of such securities
at that time shall be deemed to be in the initial bona fide offering thereof.

      3. Insofar as indemnification for liabilities arising under the Securities
Act may be permitted to directors, officers and controlling persons of the
Registrant pursuant to the foregoing provisions, or otherwise, the Registrant
has been advised that in the opinion of the Securities and Exchange Commission
such indemnification is against public policy as expressed in the Securities Act
and is, therefore, unenforceable.  In the event that a claim for indemnification
against such liabilities (other than the payment by the Registrant of expenses
incurred or paid by a director, officer or controlling person of the Registrant
in the successful defense of any action, suit or proceeding) is asserted by such
director, officer or controlling person in connection with the securities being
registered, the Registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate
jurisdiction the question whether such indemnification by it is against public
policy as expressed in the Securities Act and will be governed by the final
adjudication of such issue.

                                       3
SIGNATURES

      Pursuant to the requirements of the Securities Act of 1933, the registrant
certifies that it has reasonable grounds to believe that it meets all of the
requirements for filing on Form S-8 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Burlington, Commonwealth of Massachusetts, on
___________, 1999.

                                        DYNATECH CORPORATION

                                        By:
                                            _________________________________
                                            John F. Reno
                                            Chairman, President and
                                            Chief Executive Officer

                                       4
Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed below by the following persons in the
capacities and on the dates indicated.
Signatures                               Capacity                                  Date
---------------------------------    -----------------------------------   ------------------------------------
Chairman of the Board of              
_________________________________    Directors, President, Chief           ____________________________, 1999
John F. Reno                         Executive Officer and
                                     Director
                                     
                                     
                                     
                                     Vice President, Chief
                                     Financial Officer, Treasurer
_________________________________    (Principal Financial Officer),        ____________________________, 1999
Allan M. Kline                       and Director
                                     
                                     
                                     
                                     Corporate Vice President -
_________________________________    Communications Test                   ____________________________, 1999
John R. Peeler                       Business, and Director
                                     

_________________________________                                          ____________________________, 1999
Brian D. Finn                        Director
                       
                                     
_________________________________    Director                              ____________________________, 1999
Charles P. Pieper                    

                                     
_________________________________    Director                              ____________________________, 1999
Joseph L. Rice, III                  
                                     

_________________________________    Director                              ____________________________, 1999
Ned C. Lautenbach                    

                                     
_________________________________    Director                              ____________________________, 1999
Brian H. Rowe                        
                                     

_________________________________    Director                              ____________________________, 1999
Marvin L. Mann
5
EXHIBIT INDEX
                                   -------------
Exhibit                                                                                      Sequential
  Number                                                                                       Page Number
----------                                                                                    -------------
3.1           Amended and Restated Articles of Organization of the                                  --
              Registrant - filed as Exhibit 3(1) to the Registrant's
              Annual Report on 10-K for the fiscal year ended
              March 31, 1998 and incorporated herein by reference.

3.2           By-Laws filed as Exhibit 3.2(ii) to the Registrant's                                  --
              Annual Report on Form 10-K for the fiscal year ended
              March 31, 1998 and incorporated herein by reference.

4.1           Specimen Certificate of Common Stock of the                                           --
              Registrant (filed herein).

5             Opinion of Mark V. B. Tremallo, Dynatech                                              --
              Corporation's General Counsel (filed herein)

23.1          Consent of Mark V.B. Tremallo, Dynatech                                               --
              Corporation's General Counsel's consent is stated with
              said counsel's opinion as Exhibit No. 5 (filed herein)

23.2          Consent of PricewaterhouseCoopers L.L.P. (filed                                       --
              herein)

24            Power of Attorney (filed herein).                                                     --

99(i)         Dynatech Corporation Amended and Restated 1994                                        --
              Stock Option and Incentive Plan (filed herein)

99(ii)        Dynatech Corporation Non-Employee Directors Stock                                     --
              Incentive Plan (filed herein).