PATS, INC.

                                   BY-LAWS



                                  ARTICLE I.

                                 STOCKHOLDERS


          SECTION 1.01.  ANNUAL MEETINGS.  The Corporation shall hold each 
year, commencing with the year 1977, an annual meeting of the stockholders 
for the election of directors and the transaction of any business within the 
powers of the Corporation, on the second Friday of September in each year if 
not a legal holiday, and if a legal holiday, then on the first day following 
which is not a Sunday or a legal holiday. Any business of the Corporation may 
be transacted at an annual meeting without being specially designated in the 
notice, except such business as is specifically required by statute or by the 
charter to be stated in the notice. Failure to hold an annual meeting at the 
designated time shall not, however, invalidate the corporation existence or 
affect otherwise valid corporate acts.

          SECTION 1.02.  SPECIAL MEETINGS.  At any time in the interval 
between annual meetings, special meetings of the stockholders may be called 
by the President or by a majority of the Board of Directors by vote at a 
meeting or in writing with or without a meeting.

          SECTION 1.03.  PLACE OF MEETINGS.  All meetings of stockholders 
shall be held at the principal office of the Corporation in Howard County, 
Maryland, except in cases in which the notice thereof designates dome other 
place; but all such meetings shall be held within the State of Maryland.

          SECTION 1.04.  NOTICE OF MEETINGS.  Not less than ten days nor more 
than ninety days before the date of every stockholders' meeting, the Secretary 
shall give to each stockholder entitled to vote at such meeting, written or 
oral notice stating the time and place of the meeting, and in the case of a 
special meeting, the purpose or purposes for which the meeting is called, 
either by mail or by presenting it to him personally or by leaving it at his 
residence or usual place of business.  If mailed, such notice shall be deemed 
to be given when deposited in the United States mail addressed to the 
stockholder at his post office address as it appears on the records of the 
Corporation, with postage thereon prepaid. Notwithstanding the foregoing 
provision, a waiver of notice in writing, signed by the person or persons 
entitled to such notice and filed with the records of the meeting, whether 
before or after the holding thereof, or actual attendance at the meeting in 
person or by proxy, shall be deemed equivalent to the giving of such notice 
to such persons. Any meeting of stockholders, annual or special, may adjourn 
from time to time to reconvene at the same or some other place, and no notice 
need be given of any such adjourned meeting other than by announcement.

          SECTION 1.05.  VOTES REQUIRED.  Actions required to be voted on by 
the stockholders in accordance with the "Corporation and Association" Article 
of the Maryland Annotated Code, shall be passed by the majority vote of 
stockholders entitled to vote.




                                                                           2.

          SECTION 1.06.  LIST OF STOCKHOLDERS.  At each meeting of 
stockholders a full, true and complete list in alphabetical order, or in 
alphabetical order by classes of stock, or all stockholders entitled to vote 
at such meeting, certifying the number of class of shares held by each, shall 
be furnished by the Secretary.

          SECTION 1.07.  VOTING FOR DIRECTORS.  Directors shall be elected 
by the majority vote of all stockholders entitled to vote. Each stockholder 
will have one and only one vote (cumulative voting is prohibited) for each 
position on the Board of Directors for which an election is being held.


                                 ARTICLE II.

                             BOARD OF DIRECTORS


          SECTION 2.01.  POWERS.  The business and affairs of the Corporation 
shall be managed by its Board of Directors. The Board of Directors may 
exercise all the powers of the Corporation, except such as are by statute or 
the charter or by By-Laws conferred upon or reserved to the stockholders. The 
Board of Directors shall keep full and fair accounts of its transactions.

          SECTION 2.02.  NUMBER OF DIRECTORS.  The number of directors of the 
Corporation shall be FOUR (4). By vote of three which constituted a majority 
of the entire Board of Directors, the number of directors may be increased or 
decreased, from time to time, to not exceeding twenty nor less than three 
directors.

          SECTION 2.03.  ELECTION OF DIRECTORS.  Until the first annual 
meeting of a stockholders or until successors are duly elected and qualify, 
the Board shall consist of the persons named as such in the Charter. At the 
first annual meeting of stockholders and at each annual meeting thereafter, 
the stockholders shall elect directors to hold office until the next 
succeeding annual meeting or until their successors are elected and qualify. 
At any meeting of stockholders, duly called, the stockholders may, by the 
affirmative vote of the holders of a majority of the votes entitled to be 
cast thereon, remove any director or directors from office and may elect a 
successor or successors to fill any resulting vacancies for the unexpired 
terms of removed directors.

          SECTION 2.04.  VACANCIES.  Any vacancy occurring in the Board of 
Directors for any cause other than by reason of an increase in the number of 
directors may be filled by a majority of the remaining members of the Board 
of Directors, even if such remaining members do not constitute a quorum. Any 
vacancy occurring by reason of an increase in the number of directors may be 
filled by action of a majority of the entire Board of Directors. A director 
elected to hold office until the next annual meeting of stockholders or until 
his successor is elected and qualifies.

          SECTION 2.05.  REGULAR MEETINGS.  After each meeting of 
stockholders at which a Board of Directors shall have been elected, the board 
of Directors so elected shall meet as soon as practicable for the purpose of 
organization and the transaction of other business at such time as may be 
designated by the stockholders at such meeting. The first meeting shall be 
held at the place designated by the Board of Directors for such first regular 
meeting or at the office of the Corporation in Howard county, Maryland. No 
notice of such first meeting shall be necessary if held as hereinabove 
provided. Other regular meetings of the Board of




                                                                           3.

Directors shall be held on such dates and at such places within or without 
the State of Maryland as may be designated from time to time by the Board of 
Directors.

          SECTION 2.06.  SPECIAL MEETINGS.  Special meetings of the Board of 
Directors may be called at any time by the President or by a majority of the 
Board of Directors by vote at a meeting, or in writing with or without a 
meeting. Such special meetings shall be held at such place or places within 
or without the State of Maryland as may be designated from time to time by 
the Board of Directors.

          SECTION 2.07.  NOTICE OF MEETINGS.  Except as provided in Section 
2.05, notice of he place, day and hour of every regular and special meeting 
shall be given to each Director two days (or more) before the meeting, by 
delivering the same to him personally, or by sending the same to him by 
telegraph, or by leaving the same at his residence or usual place of 
business, or, in the alternative, by mailing such notice three days (or more) 
before the meeting, postage prepaid, and addressed to him at his last known 
post office address, according to the records of the Corporation. Unless 
required by these By-Laws or by resolution of the Board of Directors, no 
notice of any meeting of the Board of Directors need state the business to be 
transacted thereat. No notice of any meeting of the Board of Directors need 
be given to any Director who attends, or to any Director who, in writing 
executed and filed with the records of the meeting either before or after the 
holding thereof, waives such notice. Any meeting of the Board of Directors, 
regular or special, may adjourn from time to time to reconvene at the same or 
some other place, and no notice need be given of any such adjourned meeting 
other than by announcement.

          SECTION 2.08.  QUORUM.  At all meetings of the Board of Directors 
the presence of a two-thirds majority of the entire Board of Directors shall 
constitute a quorum for the transaction of business. Except in cases in which 
it is by statute, by the Charter or by the By-Laws otherwise provided, the 
vote of a simple majority of such quorum at a duly constituted meeting shall 
be sufficient to elect and pass any measure. In the absence of a quorum, the 
Directors present by majority vote and without notice other than by 
announcement may adjourn the meeting from time to time until a quorum shall 
attend.

          SECTION 2.09.  INFORMAL ACTION BY DIRECTORS.  Any action required 
or permitted to be taken at any meeting of the Board of Directors or of any 
committee thereof may be taken without a meeting, if a written consent to 
such action is signed by all members of the Board or of such committee, as 
the case may be, and such written consent is filed with the minutes of 
proceedings of the Board of Committee.


                                 ARTICLE III.

                                   OFFICERS


          SECTION 3.01.  EXECUTIVE OFFICERS.  The Board of Directors shall 
choose a President from among the Directors; and a Secretary and a Treasurer 
who need not be directors. The Board of Directors may choose one or more Vice 
Presidents. Any two or more of the above-mentioned offices, except those of 
President and a Vice President, may be held by the same person; but no 
officer shall execute, acknowledge or verify any Instructrument in more than 
one capacity. If such instrument be required by statute, by the Charter, by 
the By-Laws or by resolution of the Board of Directors to be executed, 
acknowledged or verified by any two or more officers. Each such officer shall 
hold office until the first meeting of the



                                                                           4.

Board of Directors after the annual meeting of stockholders next succeeding 
his election, and until his successor shall have been duly chosen and 
qualified, or until he shall have resigned or shall have been removed. Any 
vacancy in any of the above offices may be filled for the unexpired portion 
of the term of the Board of Directors at any regular or special meeting.

     SECTION 3.02. PRESIDENT. The President shall preside at all meetings of 
the stockholders and of the Board of Directors at which he shall be present; 
he shall have general charge and supervision of the business of the 
Corporation; he may sign and execute, in the name of the Corporation, all 
authorized deeds, mortgages, bonds, contracts or other instruments, except in 
cases in which the signing and execution thereof shall have been expressly 
delegated to some other officer or agent of the Corporation; and, in general, 
he shall perform all duties incident to the office of a president of a 
corporation, and such other duties as, from time to time, may be assigned to 
him by the Board of Directors.

     SECTION 3.03. VICE PRESIDENTS. The Vice President or Vice Presidents, at 
the request of the President or in his absence or during his inability to 
act, shall perform the duties and exercise the functions of the President, 
and when so acting shall have the powers of the President. If there be more 
than one Vice President, the President may determine which one or more of the 
Vice Presidents shall perform any of such duties or exercise any of such 
functions; otherwise any of the Vice Presidents may perform any of such 
duties or exercise any of such functions. The Vice President or Vice 
Presidents shall have such other powers and perform such other duties as may 
be assigned to him or them by the Board of Directors or the President.

     SECTION 3.04. SECRETARY. The Secretary shall keep the minutes of the 
meetings of stockholders, of the Board of Directors, and of any committees, 
in books provided for the purpose; he shall see that all notices are duly 
given in accordance with the provisions of the By-Laws or as required by law; 
he shall be custodian of the records of the Corporation; and, in general, he 
shall perform all duties incident to the office of a secretary of a 
corporation, and such other duties as, from time to time, may be assigned to 
him by the Board of Directors or the President.

     SECTION 3.05. TREASURER. The Treasurer shall have charge of and be 
responsible for all funds, securities, receipts and disbursements of the 
Corporation, and shall deposit or cause to be deposited, in the name of the 
Corporation, all moneys or other valuable effects in such banks trust 
companies or other depositories as shall, from time to time, be selected by 
the Board of Directors; he shall render to the President and to the Board of 
Directors whenever requested, an account of the financial condition of the 
Corporation, and, in general, he shall perform all the duties incident to the 
office of a treasurer of a corporation, and such other duties as may be 
assigned to him by the Board of Directors or the President.

     SECTION 3.06. SUBORDINATE OFFICERS. The Board of Directors may from time 
to time appoint such subordinate officers as it may deem desirable. Each such 
officer shall hold office for such period and perform such duties as the 
Board of Directors or the President may prescribe. The Board of Directors, 
may from time to time authorize any committee or officer to appoint and 
remove subordinate officers and prescribe the duties thereof.

     SECTION 3.07. COMPENSATION. The Board of Directors shall have power to 
fix the compensation of all officers of the Corporation.




                                                                           5.

     SECTION 3.08. REMOVAL. Any officer or agent of the Corporation may be 
removed by the Board of Directors whenever, in its judgement, the best 
interest of the Corporation will be served thereby, but such removal shall be 
without prejudice to the contractual rights, if any, of the person so 
removed.

                                    ARTICLE IV.

                                      STOCK

     SECTION 4.01. CERTIFICATES. Each stockholder shall be entitled to a 
certificate or certificates which shall represent and certify the number and 
kind of shares of stock owned by him in the Corporation. Such certificates 
shall be signed by the President or a Vice President and countersigned by the 
Secretary or the Treasurer. Stock certificates shall be in such form, not 
inconsistent with law or with the Charter, as shall be approved by the Board 
of Directors. In case any officer of the Corporation who has signed any 
certificate ceases to be an officer of the Corporation, whether because of 
death, resignation or otherwise, before such certificate is issued, the 
certificate may nevertheless be issued and delivered by the Corporation as if 
the officer had not ceased to be such officer as of the date of its issue.

     SECTION 4.02. TRANSFERS. The Board of Directors shall have power and 
authority to make such rules and regulations as it may deem expedient 
concerning the issue and transfer of certificates of stock.

     SECTION 4.03. STOCK LEDGERS. Original or duplicate stock ledgers, 
containing the names and addresses of the stockholders of the Corporation and 
the number of shares of each class held by them respectively, shall be kept 
at an office of the Corporation.

     SECTION 4.04. RECORD DATES. The Board of Directors is hereby empowered 
to fix, in advance, a date as the record date of the purpose of determining 
stockholders entitled to notice of, or to vote at, any meeting of 
stockholders, or stockholders entitled to receive payment of any dividend or 
the allotment of any rights, or in order to make a determination of 
stockholders for any other proper purpose.

     SECTION 4.05. NEW CERTIFICATES. In case any certificate of stock is 
lost, stolen, mutilated or destroyed, the Board of Directors may authorize 
the issuance of a new certificate in place thereof upon such terms and 
conditions as it may deem advisable; or the Board of Directors may delegate 
such power to any officer or officers of the Corporation; but the Board of 
Directors or such officer or officers, in their discretion, may refuse to 
issue such new certificate save upon the order of some court having 
jurisdiction in the premises.

                                ARTICLE V.

                                 FINANCE

     SECTION 5.01. CHECKS, DRAFTS, ETC. Checks, drafts, and orders for the 
payment of money, notes and other evidence of indebtedness, issued in the 
name of the Corporation in the amount of One Hundred Thousand  Dollars 
($100,000) or less, shall, unless otherwise provided by resolution of the 
Board of Directors, be signed by either the President, Vice President of 
Finance or the Treasurer.




                                                                           6.

     Checks, drafts, and orders for the payment of money, notes and other 
evidence of indebtedness, issued in the name of the Corporation in an amount 
in excess of One Hundred Thousand Dollars ($100,000), shall, unless 
otherwise provided by resolution of the Board of Directors, be signed by both 
the President, Vice President of Finance or the Treasurer jointly.

     SECTION 5.02. ANNUAL REPORTS. There shall be prepared annually a full 
and correct statement of the affairs of the Corporation, including a balance 
sheet and a financial statement of operations for the preceding fiscal year, 
which shall be submitted at the annual meeting of the Board of Directors and 
filed within twenty days thereafter at the principal office of the 
Corporation in this State.

                              ARTICLE VI.

                           SUNDRY PROVISIONS

     SECTION 6.01. AMENDMENTS. Any and all provisions of these By-Laws may be 
altered or repealed and new By-Laws may be adopted at any annual meeting of 
the stockholders, or at any special meeting called for that purpose. In 
addition, the Board of Directors shall have the power at any regular or 
special meeting thereof, to make and adopt new by-laws or to amend, alter or 
repeal any by-law of the Corporation.