AMENDMENT TO

                        ASSET PURCHASE AND SALE AGREEMENT

         This AMENDMENT TO ASSET PURCHASE AND SALE  AGREEMENT  ("Amendment")  is
dated as of December 13, 1999 (the "Effective Date"), and is entered into by and
between  Kavouras,   Inc.,  a  Minnesota  corporation  ("Seller"),   and  Radtec
Engineering, Inc., a Colorado corporation ("Buyer").

                                    RECITALS:

         A. Buyer and Seller all of the present  parties to that  certain  Asset
Purchase and Sale Agreement dated December 8, 1999 (the "Agreement").

         B.  Buyer and  Seller  desire  to amend and  modify  the  Agreement  as
specifically  set forth in this  Amendment  to complete  the  allocation  of the
purchase  price under the  Agreement  and to recognize  that the  Trademark  (as
defined in the Agreement) has not been registered by Seller.

         NOW, THEREFORE, in consideration of the Recitals which are incorporated
into and made a part of this  Amendment and the mutual  covenants and agreements
set forth therein and herein, the parties hereto agree as follows:

         1.  Amendments  to Agreement.  (a) From and after the  Effective  Date,
Schedule 2 of the  Agreement  is deleted in its entirety and Schedule 2 attached
to this Amendment is inserted in its place.

         (b) From and after the Effective  Date,  the word  "registered"  in the
first sentence of Section 1(d) of the Agreement is deleted.

         (c) From and after the Effective  Date, the first sentence of Section 4
of the Agreement is deleted in its entirety and the following is inserted in its
place:

         "Seller shall sell, transfer,  assign,  convey, and deliver to Buyer at
         the Closing the Assets by (i) a warranty bill of sale and assignment in
         the form of Exhibit B hereto,  (ii) an  Assignment  of Trademark in the
         form of  Exhibit C hereto to  transfer  the  Trademark,  and (iii) such
         other good and sufficient instruments of sale,  assignment,  conveyance
         and transfer as shall be required to  effectively  vest in Buyer all of
         Seller's  right,  title,  and  interest in and to the Assets,  free and
         clear of all liens, encumbrances,  security interests,  actions, claims
         and equities of any kind whatsoever."

         (d) From and after the  Effective  Date,  Exhibit C of the Agreement is
deleted in its entirety and Exhibit C attached to this  Amendment is inserted in
its place.

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<PAGE>

         2. Binding  Effect.  This Amendment  shall be binding upon and inure to
the benefit of Buyer and Seller and their  respective  successors  and permitted
assigns.

         3.  Superseding.  From and after the Effective  Date, all references to
the Agreement shall mean the Agreement, as amended by this Amendment.

         4.  Confirmation.  Except  as  otherwise  expressly  set  forth in this
Amendment,  the  Agreement is hereby  ratified and confirmed and remains in full
force and effect.

         5.  Counterparts.  This  Amendment  may be  executed  in any  number of
counterparts,  all of which taken  together  shall  constitute  one and the same
instrument  and any of the parties  hereto may execute this Amendment by signing
any such counterpart.

         IN WITNESS WHEREOF,  the parties have executed this Amendment as of the
date and year first above written.

                                Kavouras, Inc., a Minnesota corporation

                                By:/s/ Laura Burrow
                                   -------------------------------
                                    Laura Burrow, Vice President



                                Radtec Engineering, Inc., a Colorado corporation

                                By: /s/ Dennis Treddenick
                                    ---------------------------------
                                    Dennis Treddenick, Vice President


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<PAGE>



                                   SCHEDULE 2

                          Allocation of Purchase Price


"The reporting  person agrees to furnish  supplementally  a copy of this omitted
schedule to the Securities and Exchange Commission upon request."

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<PAGE>

                                    EXHIBIT C

                             ASSIGNMENT OF TRADEMARK

         THIS  ASSIGNMENT is made this 13th day of December,  1999, by KAVOURAS,
INC., a Minnesota  corporation  ("Assignor"),  of 11400 Rupp Drive,  Burnsville,
Minnesota  55337-1279,  to RADTEC  ENGINEERING,  INC.,  a  Colorado  corporation
("Assignee"), of 2150 West 6th Avenue, Broomfield, Colorado 80020.

                                    RECITALS:

         A. Assignor uses the trademark "Triton Doppler Radar" (the "Mark").

         B. Assignee is acquiring the portion of Assignor's  business pertaining
to the  manufacture,  sale,  installation  and service of a line of Klystron and
TWT-based  Doppler weather radar systems know as the Triton Doppler Radar Series
(the "Business") and in connection  therewith all of Assignor's right, title and
interest in and to the Mark.

         NOW THEREFORE,  for valuable consideration,  receipt of which is hereby
acknowledged:

         Assignor hereby assigns to Assignee all of Assignor's right,  title and
interest in and to the Mark,  together  with all of the goodwill of the Business
in  connection  with which the Mark is used and which is symbolized by the Mark,
and the right to recover for past infringement of the Mark;  provided,  however,
this  Assignment  does  not  include  the  other   registered  and  unregistered
trademarks  and service  marks of Assignor  which include the word "Triton" (the
"Excluded Marks"),  including,  without limitation,  the marks "Triton", "Triton
X", "Triton Art Paint", "Triton i7", and "Triton RT". This Assignment is subject
to the retention by Assignor of all of its rights,  title and interest in and to
the Excluded  Marks and the  registrations  and  applications  for  registration
therefor.

                                         KAVOURAS, INC., a Minnesota corporation


                                         By: /s/ Laura Burrow
                                             ----------------------------
                                             Laura Burrow, Vice President

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