Exhibit 10.bb

FIRST AMENDMENT TO  PARTICIPATION AGREEMENT

THIS
FIRST AMENDMENT TO PARTICIPATION AGREEMENT, dated as of January 29, 2001 (this " Amendment"), amends the Participation Agreement, dated as of October 22, 1999 (the " Participation Agreement"), by and among ADC Telecommunications, Inc., a Minnesota corporation, as Lessee; Lease Plan North America, Inc., not in its individual capacity, except as
expressly stated therein, but solely as Agent Lessor for the Participants; the Persons named on Schedule I thereto, as Participants; and ABN AMRO Bank N.V., as Administrative Agent. Capitalized
terms used herein and not otherwise defined herein shall have the respective meanings assigned thereto in Appendix 1 to the Participation Agreement.

WHEREAS,
the parties hereto have entered into the Participation Agreement and the other Operative Documents to fund the Construction of the Financed Improvements on the Land; and

WHEREAS,
the parties hereto desire to amend the Participation Agreement as hereinafter set forth;

NOW,
THEREFORE, in consideration of the premises and for other good and valuable consideration (the receipt and sufficiency of which are hereby acknowledged), the parties hereto agree as
follows:

SECTION
1 AMENDMENTS. Effective as of the date hereof and subject to the satisfaction of the condition precedent set forth in Section 2, the Participation Agreement shall be amended in accordance with Sections 1.1-1.6.

SECTION
1.1 ERISA Compliance. Section 7.2(l)(iii) of the Participation Agreement is hereby amended and restated in its entirety to read as follows:



SECTION
1.2 Covenants of Lessee. Section 8.1(i)(v)(F)(C) of the Participation Agreement is hereby amended and restated in its entirety to read as follows:



SECTION
1.3 Limitation on Liens. Section 8.2(l) of the Participation Agreement is hereby amended and restated in its entirety to read as follows:



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SECTION
1.4 Limitation on Indebtedness. Section 8.6(d) of the Participation Agreement is hereby amended by deleting the reference to "$25,000,000" appearing therein and replacing it with a reference to
"$50,000,000".

SECTION
1.5 Lease Obligations. Section 8.10 of the Participation Agreement is hereby amended by (a) deleting the word "and" at the end of clause (b) thereof, (b) changing the
reference to clause (c) thereof to clause (d), and (c) adding the following new clause (c) immediately after clause (b) thereof:

"(c)
Sale and Leaseback Transactions; and".

SECTION
1.6 Sale and Leaseback Transactions. Appendix 1 to the Participation Agreement is hereby amended by adding thereto the following new defined term "Sale and Leaseback Transaction" in proper
alphabetical
order:



SECTION
2 CONDITION PRECEDENT. This Amendment shall become effective as of the date hereof when the Agent Lessor shall have received this Amendment, duly executed by each of the parties
hereto.

SECTION
3 REPRESENTATIONS AND WARRANTIES. Each of the parties hereto hereby represents and warrants that (a) the execution, delivery and performance of this Amendment has been
duly authorized by such party, (b) the person executing this Amendment on its behalf has been duly authorized to act on its behalf, (c) this Amendment constitutes its legal, valid,
binding and enforceable agreement, except as enforceability may be limited by bankruptcy, insolvency, reorganization, moratorium or other laws or equitable principles relating to or limiting the
rights of creditors generally and (d) its entry into this Amendment will not violate any agreement, law, rule or regulation by which it is bound or by which any of its assets are affected.

SECTION
4 MISCELLANEOUS.

SECTION
4.1 Continuing Effectiveness, etc. This Amendment shall be deemed to be an amendment to the Participation Agreement, and the Participation Agreement, as amended hereby, and each other Operative
Document, shall
remain in full force and effect and are hereby ratified, approved and confirmed in each and every respect. On and after the date hereof, all references to the "Participation Agreement" in the
Operative Documents or in any other document, instrument, certificate, agreement, opinion or writing shall be deemed to refer to the Participation Agreement as amended hereby. Except as expressly set
forth herein, the execution, delivery and effectiveness of this Amendment shall not operate as an amendment, modification or waiver of any provision, right, power or remedy of any party hereto under
any Operative Document.

SECTION
4.2 Severability. Any provision of this Amendment which is prohibited or unenforceable in any jurisdiction shall, as to such provision and such jurisdiction, be ineffective to the extent of
such prohibition or unenforceability without invalidating the remaining provisions of this Amendment or affecting the validity or enforceability of such provision in any other jurisdiction.

2

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SECTION
4.3 Headings. The various headings of this Amendment are inserted for convenience of reference only and shall not affect the meaning or interpretation of this Amendment or any provisions
hereof.

SECTION
4.4 Execution in Counterparts. This Amendment may be executed by the parties hereto in several counterparts, each of which shall be deemed to be an original and all of which shall constitute together
but
one and the same agreement.

SECTION
4.5 Governing Law.THIS AMENDMENT SHALL IN ALL RESPECTS BE GOVERNED BY THE INTERNAL LAW OF THE STATE OF NEW YORK AS TO ALL MATTERS OF CONSTRUCTION, VALIDITY AND PERFORMANCE, WITHOUT REGARD TO
CONFLICTS OF LAW PRINCIPLES, EXCEPT TITLE 14 OF ARTICLE 5 OF THE NEW YORK GENERAL OBLIGATIONS LAW.This Amendment constitutes the entire understanding among the parties hereto with respect to the subject matter hereof and
supersedes any prior agreement, written or oral,
with respect thereto.

SECTION
4.6 Successors and Assigns. This Amendment shall be binding upon and shall inure to the benefit of the parties hereto and their respective successors and assigns.

[SIGNATURE
PAGES FOLLOW]

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IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be executed by their respective officers thereunto duly authorized as of the day and year first above written.

| |  | ADC TELECOMMUNICATIONS, INC., as Lessee
| |  | ---------------------------------------
| |  | By:                                    
| |  |                                        
| |  | Name:                                  
| |  |                                        
| |  | Title:                                 
| |  |                                        

S-1

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| |  | LEASE PLAN NORTH AMERICA, INC., not in its individual capacity, except as expressly stated in the Participation Agreement, but solely as Agent Lessor
| |  | -----------------------------------------------------------------------------------------------------------------------------------------------------
| |  | By:                                                                                                                                                  
| |  |                                                                                                                                                      
| |  | Name:                                                                                                                                                
| |  |                                                                                                                                                      
| |  | Title:                                                                                                                                               
| |  |                                                                                                                                                      

S-2

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| |  | AMSTERDAM FUNDING CORPORATION, as a Participant
| |  | -----------------------------------------------
| |  | By:                                            
| |  |                                                
| |  | Name:                                          
| |  |                                                
| |  | Title:                                         
| |  |                                                

S-3

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| |  | ABN AMRO BANK N.V., as a Participant
| |  | ------------------------------------
| |  | By:                                 
| |  |                                     
| |  | Name:                               
| |  |                                     
| |  | Title:                              
| |  |                                     
| |  | By:                                 
| |  |                                     
| |  | Name:                               
| |  |                                     
| |  | Title:                              
| |  |                                     

S-4

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