FORM OF WARRANT

Exhibit 2.3

FORM OF WARRANT

This Warrant and any securities acquired upon exercise of this Warrant have not been registered under the Securities Act of 1933, as amended, or any state securities laws. The securities may not be offered for sale, sold, transferred or assigned in the absence of an effective registration statement for the securities under such Act or applicable state securities laws or pursuant to an applicable exemption to the registration requirements of such Act and such laws.

HEI, INC.

COMMON STOCK PURCHASE WARRANT

     HEI, Inc., a Minnesota corporation (the “ Company ”), hereby agrees that, for value received, ___, or its assigns (the “ Holder ”), is entitled, subject to the terms set forth below, to purchase from the Company, in whole or in part, at any time after May ___, 2005 and until ___, 2010 at 5:00 p.m., Minneapolis, Minnesota time (the “ Expiration Date ”), [ 40% of shares purchased (as converted) ] shares of Common Stock, par value $.05 per share, of the Company (the “ Common Stock ”), at an exercise price of $[ 110% of Market Value ] per share of Common Stock (subject to adjustment as provided herein, the “ Exercise Price ”).

1. Exercise of Warrant . This Common Stock Purchase Warrant (this “ Warrant ”) may be exercised by the Holder, in whole or in part (but in minimum quantities of 10,000 shares), at any time on and after the date hereof and prior to the Expiration Date (the “ Warrant Exercise ”), by surrendering this Warrant with the form of exercise attached hereto duly executed by the Holder, to the Company at its principal office, accompanied by payment, in cash or by cashier’s check payable to the order of the Company, of the Exercise Price payable in respect of the Common Stock being purchased. If less than all of the Common Stock purchasable hereunder is purchased, the Company will, upon the Warrant Exercise, execute and deliver to the Holder a new warrant (dated as of the date hereof) evidencing the number of shares of Common Stock not so purchased. As soon as practicable after the Warrant Exercise and payment of the Exercise Price, the Company will use its best efforts to issue in the name of and deliver to the Holder, or as the Holder may direct, a certificate or certificates representing the shares of Common Stock purchased pursuant to the Warrant Exercise. The Company may require that such certificate or certificates contain on the face thereof a legend substantially as follows:

“The transfer of the shares represented by this certificate is restricted pursuant to the terms of a Common Stock Purchase Warrant dated May ___, 2005, issued by HEI, Inc., a copy of which is available for inspection at the principal office of HEI, Inc. Transfer may not be made except in accordance with the terms of the

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Common Stock Purchase Warrant. In addition, no sale, offer to sell or transfer of the shares represented by this certificate shall be made unless a registration statement under the Securities Act of 1933, as amended (the “ 1933 Act ”), with respect to such shares is then in effect or an exemption from the registration requirements of the 1933 Act is then in fact applicable to such shares.”

2. Negotiability and Transfer . This Warrant is issued upon the following terms, to which the Holder consents and agrees:

      2.1 Absolute Owner . Until this Warrant is duly transferred on the books of the Company, the Company may treat the registered Holder as absolute owner hereof for all purposes without being affected by any notice to the contrary.

      2.2 Successive Holder . Each successive holder of this Warrant, or of any portion of the rights represented thereby, shall be bound by the terms and conditions set forth herein.

3. Antidilution Adjustments .

      3.1 Exercise Price Adjustment . If the Company shall at any time hereafter effect a subdivision or combination of its outstanding shares of Common Stock, or declare a dividend payable in Common Stock, the Exercise Price in effect immediately prior to the subdivision, combination or record date for such dividend payable in Common Stock shall be proportionately increased, in the case of combination, or proportionately decreased, in the case of subdivision or declaration of a dividend payable in Common Stock, and each share of Common Stock purchasable upon the Warrant Exercise, immediately preceding such event, shall be changed to the number determined by dividing the then current Exercise Price by the exercise price as adjusted after such subdivision, combination or dividend payable in Common Stock.

      3.2 Fractional Shares . No fractional shares of Common Stock are to be issued upon the Warrant Exercise, but the Company shall pay a cash adjustment in respect of any fraction of a share which would otherwise be issuable in an amount equal to the same fraction of the market price per share of Common Stock on the date of exercise as determined in good faith by the Company.

      3.3 Reorganization, Sale of Assets and Merger . In case of any capital reorganization or any reclassification of the Common Stock, or in the case of any consolidation with or merger of the Company into or with another corporation, or the sale of all or substantially all of its assets to another corporation, which is effected in such a manner that the holders of Common Stock shall be entitled to receive stock, securities or assets with respect to or in exchange for Common Stock, then, as a part of such reorganization, reclassification, consolidation, merger or sale, as the case may be, lawful provision shall be made so that the Holder shall have the