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                                                                    Exhibit 10.8


                              DYNATECH CORPORATION

                        1996 EMPLOYEE STOCK PURCHASE PLAN

                                 April 19, 1996


         The purpose of this Plan is to provide eligible employees of DYNATECH
CORPORATION (the "Company") and certain of its subsidiaries with opportunities
to purchase shares of the Company's common stock, $.20 par value (the "Common
Stock"), commencing on October 1, 1996. Six Hundred Thousand (600,000) shares of
Common Stock in the aggregate have been approved for this purpose.

         1. ADMINISTRATION. The Plan will be administered by the Company's Board
of Directors (the "Board") or by a Committee appointed by the Board (the
"Committee"). The Board or the Committee has authority to make rules and
regulations for the administration of the Plan and its interpretation and
decisions with regard thereto shall be final and conclusive.

         2. ELIGIBILITY. Participation in the Plan will neither be permitted nor
denied contrary to the requirements of Section 423 of the Internal Revenue Code
of 1986, as amended (the "Code"), and regulations promulgated thereunder. All
employees of the Company, including Directors who are employees, and all
employees of any subsidiary of the Company (as defined in Section 424(f) of the
Code) designated by the Board or the Committee from time to time (a "Designated
Subsidiary"), are eligible to participate in any one or more of the offerings of
Options (as defined in Section 9) to purchase Common Stock under the Plan
provided that they are employees of the Company or a Designated Subsidiary on
the first day of the applicable Plan Period (as defined below).

         No employee may be granted an option hereunder if such employee,
immediately after the option is granted, owns 5% or more of the total combined
voting power or value of the stock of the Company or any subsidiary. For
purposes of the preceding sentence, the attribution rules of Section 424(d) of
the Code shall apply in determining the stock ownership of an employee, and all
stock which the employee has a contractual right to purchase shall be treated as
stock owned by the employee.

         3. OFFERINGS. The Company will make one or more offerings ("Offerings")
to employees to purchase stock under this Plan. Offerings will begin each
October 1 and April 1, or the first business day thereafter (the "Offering
Commencement Dates"); the first Offering shall begin on October 1, 1996. Each
Offering Commencement Date will begin a six (6) month period (a "Plan 

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Period") during which payroll deductions will be made and held for the purchase
of Common Stock at the end of the Plan Period. The Board or the Committee may,
at its discretion, choose a different Plan Period of twelve (12) months or less
for subsequent Offerings.

         4. PARTICIPATION. An employee eligible on the Offering Commencement
Date of any Offering may participate in such Offering by completing and
forwarding a payroll deduction authorization form to the employee's appropriate
payroll office at least 30 days (or such other period as may be established by
the Board or the Committee) prior to the applicable Offering Commencement Date.
The form will authorize a regular payroll deduction from the Compensation
received by the employee during the Plan Period. Unless an employee files a new
form or withdraws from the Plan, his deductions and purchases will continue at
the same rate for future Offerings under the Plan as long as the Plan remains in
effect. The term "Compensation" means the amount of money reportable on the
employee's Federal Income Tax Withholding Statement, excluding overtime, shift
premium, incentive or bonus awards, allowances and reimbursements for expenses
such as relocation allowances for travel expenses, income or gains on the
exercise of Company stock options or stock appreciation rights, and similar
items, whether or not shown on the employee's Federal Income Tax Withholding
Statement, but including, in the case of salespersons, sales commissions to the
extent determined by the Board or the Committee.

         5. DEDUCTIONS. The Company will maintain payroll deduction accounts for
all participating employees. With respect to any Offering made under this Plan,
an employee may authorize a payroll deduction of a percentage of the
Compensation he or she receives during the Plan Period or such shorter period
during which deductions from payroll are made, which percentage shall be a whole
number from one through ten.

         No employee may be granted an Option (as defined in Section 9) which
permits his rights to purchase Common Stock under this Plan and any other stock
purchase plan of the Company and its subsidiaries, to accrue at a rate which
exceeds $25,000 of the fair market value of such Common Stock (determined at the
Offering Commencement Date of the Plan Period) for each calendar year in which
the Option is outstanding at any time.

         6. DEDUCTION CHANGES. An employee may decrease or discontinue his
payroll deduction once during any Plan Period, by filing a new payroll deduction
authorization form. However, an employee may not increase his payroll deduction
during a Plan Period. If an employee elects to discontinue his payroll
deductions during a Plan Period, but does not elect to withdraw his funds
pursuant to Section 8 hereof, funds deducted prior to 


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his election to discontinue will be applied to the purchase of Common Stock on
the Exercise Date (as defined below).

         7. INTEREST. Interest will not be paid on any employee accounts, except
to the extent that the Board or the Committee, in its sole discretion, elects to
credit employee accounts with interest at such per annum rate as it may from
time to time determine.

         8. WITHDRAWAL OF FUNDS. An employee may at any time prior to the close
of business on the last business day in a Plan Period and for any reason
permanently draw out the balance accumulated in the employee's account and
thereby withdraw from participation in an Offering. Partial withdrawals are not
permitted. The employee may not begin participation again during the remainder
of the Plan Period. The employee may participate in any subsequent Offering in
accordance with terms and conditions established by the Board or the Committee,
except that employees who are also directors or officers of the Company within
the meaning of Section 16 of the Securities Exchange Act of 1934, as amended
(the "Exchange Act") and the rules promulgated there under may not participate
again for a period of at least six (6) months as provided in Rule 16b-3(d)(2)(i)
or any successor provision.

         9. PURCHASE OF SHARES. On the Offering Commencement Date of each Plan
Period, the Company will grant to each eligible employee who is then a
participant in the Plan an option ("Option") to purchase on the last business
day of such Plan Period (the "Exercise Date"), at the Option Price hereinafter
provided for, such number of whole shares of Common Stock of the Company
reserved for the purposes of the Plan determined by dividing 10% of such
employee's Compensation for the immediately prior six-month period by the price
determined in accordance with the formula set forth in the following paragraph
but using the closing price on the Offering Commencement Date of such Plan
Period and rounding the result of such calculation down to the nearest whole
share.

         The purchase price for each share purchased will be 85% of the closing
price of the Common Stock on (i) the first business day of such Plan Period or
(ii) the Exercise Date, whichever closing price shall be less. Such closing
price shall be (a) the closing price on any national securities exchange on
which the Common Stock is listed, (b) the closing price of the Common Stock on
the Nasdaq National Market or (c) the average of the closing bid and asked
prices in the over-the-counter-market, whichever is applicable, as published in
THE WALL STREET JOURNAL. If no sales of Common Stock were made on such a day,
the price of the Common Stock for purposes of clauses (a) and (b) above shall be
the 


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reported price for the next preceding day on which sales were made.

         Each employee who continues to be a participant in the Plan on the
Exercise Date shall be deemed to have exercised his Option at the Option Price
on such date and shall be deemed to have purchased from the Company the number
of full shares of Common Stock reserved for the purpose of the Plan that his
accumulated payroll deductions on such date will pay for pursuant to the formula
set forth above (but not in excess of the maximum number determined in the
manner set forth above).

         Any balance remaining in an employee's payroll deduction account at the
end of a Plan Period will be automatically refunded to the employee, except that
any balance which is less than the purchase price of one share of Common Stock
will be carried forward into the employee's payroll deduction account for the
following Offering, unless the employee elects not to participate in the
following Offering under the Plan, in which case the balance in the employee's
account shall be refunded.

         10. ISSUANCE OF CERTIFICATES. Certificates representing shares of
Common Stock purchased under the Plan may be issued only in the name of the
employee, in the name of the employee and another person of legal age as joint
tenants with rights of survivorship, or (in the Company's sole discretion) in
the street name of a brokerage firm, bank or other nominee holder designated by
the employee.

         11. RIGHTS ON RETIREMENT, DEATH OR TERMINATION OF EMPLOYMENT. In the
event of a participating employee's termination of employment prior to the last
business day of a Plan Period, no payroll deduction shall be taken from any pay
due and owing to an employee and the balance in the employee's account shall be
paid to the employee or, in the event of the employee's death, (a) to a
beneficiary previously designated in a revocable notice signed by the employee
(with any spousal consent required under state law) or (b) in the absence of
such a designated beneficiary, to the executor or administrator of the
employee's estate or (c) if no such executor or administrator has been appointed
to the knowledge of the Company, to such other person(s) as the Company may, in
its discretion, designate. If, prior to the last business day of the Plan
Period, the Designated Subsidiary by which an employee is employed shall cease
to be a subsidiary of the Company, or if the employee is transferred to a
subsidiary of the Company that is not a Designated Subsidiary, the employee
shall be deemed to have terminated employment for the purposes of this Plan.


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         12. OPTIONEES NOT STOCKHOLDERS. Neither the granting of an Option to an
employee nor the deductions from his pay shall constitute such employee a
stockholder of the shares of Common Stock covered by an Option under this Plan
until such shares have been purchased by and issued to him.

         13. RIGHTS NOT TRANSFERABLE. Rights under this Plan are not
transferable by a participating employee other than by will or the laws of
descent and distribution, and are exercisable during the employee's lifetime
only by the employee.

         14. APPLICATION OF FUNDS. All funds received or held by the Company
under this Plan may be combined with other corporate funds and may be used for
any corporate purpose.

         15. ADJUSTMENT IN CASE OF CHANGES AFFECTING COMMON STOCK. In the event
of a subdivision of outstanding shares of Common Stock, or the payment of a
dividend in Common Stock, the number of shares approved for this Plan, and the
share limitation set forth in Section 9, shall be increased proportionately, and
such other adjustment shall be made as may be deemed equitable by the Board or
the Committee. In the event of any other change affecting the Common Stock, such
adjustment shall be made as may be deemed equitable by the Board or the
Committee to give proper effect to such event.

         16. MERGER. If the Company shall at any time merge or consolidate with
another corporation and the holders of the capital stock of the Company
immediately prior to such merger or consolidation continue to hold at least 80%
by voting power of the capital stock of the surviving corporation ("Continuity
of Control"), the holder of each Option then outstanding will thereafter be
entitled to receive at the next Exercise Date upon the exercise of such Option
for each share as to which such Option shall be exercised the securities or
property which a holder of one share of the Common Stock was entitled to upon
and at the time of such merger, and the Committee shall take such steps in
connection with such merger as the Committee shall deem necessary to assure that
the provisions of Paragraph 15 shall thereafter be applicable, as nearly as
reasonably may be, in relation to the said securities or property as to which
such holder of such Option might thereafter be entitled to receive thereunder.

         In the event of a merger or consolidation of the Company with or into
another corporation which does not involve Continuity of Control, or of a sale
of all or substantially all of the assets of the Company while unexercised
Options remain outstanding under the Plan, (a) subject to the provisions of
clauses (b) and (c), after the effective date of such transaction, each holder
of an outstanding Option shall be entitled, upon exercise of such 


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Option, to receive in lieu of shares of Common Stock, shares of such stock or
other securities as the holders of shares of Common Stock received pursuant to
the terms of such transaction; or (b) all outstanding Options may be cancelled
by the Board or the Committee as of a date prior to the effective date of any
such transaction and all payroll deductions shall be paid out to the
participating employees; or (c) all outstanding Options may be cancelled by the
Board or the Committee as of the effective date of any such transaction,
provided that notice of such cancellation shall be given to each holder of an
Option, and each holder of an Option shall have the right to exercise such
Option in full based on payroll deductions then credited to his account as of a
date determined by the Board or the Committee, which date shall not be less than
ten (10) days preceding the effective date of such transaction.

         17. AMENDMENT OF THE PLAN. The Board may at any time, and from time to
time, amend this Plan in any respect, except that (a) if the approval of any
such amendment by the shareholders of the Company is required by Section 423 of
the Code or by Rule 16b-3 under the Exchange Act, such amendment shall not be
effected without such approval, and (b) in no event may any amendment be made
which would cause the Plan to fail to comply with Section 16 of the Exchange Act
and the rules promulgated thereunder, as in effect from time to time, or Section
423 of the Code.

         18. INSUFFICIENT SHARES. In the event that the total number of shares
of Common Stock specified in elections to be purchased under any Offering plus
the number of shares purchased under previous Offerings under this Plan exceeds
the maximum number of shares issuable under this Plan, the Board or the
Committee will allot the shares then available on a pro rata basis.

         19. TERMINATION OF THE PLAN. This Plan may be terminated at any time by
the Board. Upon termination of this Plan all amounts in the accounts of
participating employees shall be promptly refunded.

         20. GOVERNMENTAL REGULATIONS. The Company's obligation to sell and
deliver Common Stock under this Plan is subject to listing on a national stock
exchange or quotation on the Nasdaq National Market and the approval of all
governmental authorities required in connection with the authorization, issuance
or sale of such stock.

         The Plan shall be governed by Massachusetts law except to the extent
that such law is preempted by federal law.

         The Plan is intended to comply with the provisions of Rule 16b-3
promulgated under the Securities Exchange Act of 1934,


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as amended. Any provision inconsistent with such Rule shall to that extent be
inoperative and shall not affect the validity of the Plan.

         21. ISSUANCE OF SHARES. Shares may be issued upon exercise of an Option
from authorized but unissued Common Stock, from shares held in the treasury of
the Company, or from any other proper source.

         22. NOTIFICATION UPON SALE OF SHARES. Each employee agrees, by entering
the Plan, to promptly give the Company notice of any disposition of shares
purchased under the Plan where such disposition occurs within two years after
the date of grant of the Option pursuant to which such shares were purchased.

         23. EFFECTIVE DATE AND APPROVAL OF SHAREHOLDERS. The Plan shall take
effect on April 19, 1996 subject to approval by the shareholders of the Company
as required by Rule 16b-3 under the Exchange Act and by Section 423 of the Code,
which approval must occur within twelve months of the adoption of the Plan by
the Board.

                                    Adopted by the Board of Directors
                                    on April 19, 1996 and by the Shareholders
                                    on July 30, 1996



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